Unit provenance dataset

The metre is defined by taking the speed of light in vacuum to be exactly 299 792 458 m/s, with the second defined by the caesium frequency.

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

1 statute mile = 1760 international yards = 1609.344 m exactly.

US, UK, Canada, Australia, New Zealand, South Africa

1 yard = 0.9144 m exactly (1959 international agreement).

US, UK, Canada, Australia, New Zealand, South Africa

1 foot = 0.3048 m exactly (international foot, 1959).

The US survey foot (1200/3937 m) was deprecated for new work on 31 December 2022 and differs by about 2 ppm.

US, UK, Canada, Australia, New Zealand, South Africa

1 inch = 25.4 mm exactly, fixed by the 1959 international yard and pound agreement.

US, UK, Canada, Australia, New Zealand, South Africa

1 international nautical mile = 1852 m exactly, adopted by the First International Extraordinary Hydrographic Conference (1929).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

A light-year is the distance light travels in one Julian year: 9 460 730 472 580 800 m exactly.

International Astronomical Union

One parsec is 648 000/π astronomical units ≈ 3.085 677 581 × 10¹⁶ m.

International Astronomical Union

The astronomical unit is exactly 149 597 870 700 m (IAU Resolution B2, 2012).

International Astronomical Union

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).

Bureau International des Poids et Mesures

The kilogram is defined by taking the Planck constant to be exactly 6.626 070 15 × 10⁻³⁴ J·s.

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

1 avoirdupois pound = 0.453 592 37 kg exactly (1959 international agreement).

US, UK, Canada, Australia, New Zealand, South Africa

1 avoirdupois ounce = 1/16 lb = 0.028 349 523 125 kg exactly.

US, UK, Canada, Australia, New Zealand, South Africa

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

The metric carat is exactly 200 mg, agreed internationally in 1907.

National Institute of Standards and Technology (US)

1 troy ounce = 480 grains = 0.031 103 476 8 kg exactly. Used for precious metals only.

National Institute of Standards and Technology (US)

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

The unified atomic mass unit is 1/12 the mass of a free carbon-12 atom: 1.660 539 068 92(52) × 10⁻²⁷ kg.

Experimentally determined; the last digits carry the CODATA 2022 uncertainty.

CODATA / NIST

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

Traceable to the kilogram, defined by fixing the Planck constant at 6.626 070 15 × 10⁻³⁴ J·s. Avoirdupois masses derive from the 1959 international pound (0.453 592 37 kg exactly).

Bureau International des Poids et Mesures

t/°C = T/K − 273.15. The degree Celsius has exactly the same magnitude as the kelvin.

Bureau International des Poids et Mesures

°F = °C × 9/5 + 32 exactly; the conversion is affine, not a single multiplying factor.

National Institute of Standards and Technology (US)

Traceable to the kelvin, defined by fixing the Boltzmann constant at 1.380 649 × 10⁻²³ J/K. Celsius and Fahrenheit are exact affine transforms of the kelvin scale.

Bureau International des Poids et Mesures

Traceable to the kelvin, defined by fixing the Boltzmann constant at 1.380 649 × 10⁻²³ J/K. Celsius and Fahrenheit are exact affine transforms of the kelvin scale.

Bureau International des Poids et Mesures

Traceable to the kelvin, defined by fixing the Boltzmann constant at 1.380 649 × 10⁻²³ J/K. Celsius and Fahrenheit are exact affine transforms of the kelvin scale.

Bureau International des Poids et Mesures

The litre is exactly 10⁻³ m³ (1 dm³) and is accepted for use with the SI.

Bureau International des Poids et Mesures

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

The US liquid gallon is exactly 231 cubic inches = 3.785 411 784 L.

National Institute of Standards and Technology (US)

The imperial gallon is exactly 4.546 09 L (Weights and Measures Act 1985).

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the cubic metre. The litre is exactly 10⁻³ m³; US and imperial capacity units are exact multiples fixed by statute.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived from the square metre via the length definitions above.

National Institute of Standards and Technology (US)

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

Derived quantity: a defined length divided by a defined time interval.

Bureau International des Poids et Mesures

The second is defined by taking the caesium-133 ground-state hyperfine transition frequency to be exactly 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Traceable to the second, defined by fixing the caesium-133 hyperfine transition frequency at 9 192 631 770 Hz.

Bureau International des Poids et Mesures

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

One byte is eight bits (octet) in all modern computing standards.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

1 KiB = 2¹⁰ B = 1024 B, per the IEC binary prefixes.

Institute of Electrical and Electronics Engineers

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

Decimal prefixes (kB, MB) are powers of 1000; binary prefixes (KiB, MiB) are powers of 1024 as standardised by IEC 80000-13.

International Electrotechnical Commission

1° = π/180 rad exactly; accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The radian is the coherent SI unit of plane angle; the degree is exactly π/180 rad and is accepted for use with the SI.

Bureau International des Poids et Mesures

The DTP/PostScript point is exactly 1/72 inch (0.352 777… mm).

Historic Didot and American printer’s points differ and are not interchangeable.

Adobe Systems / W3C

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Traceable to the ampere, defined by fixing the elementary charge at 1.602 176 634 × 10⁻¹⁹ C.

Bureau International des Poids et Mesures

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

The thermochemical calorie is exactly 4.184 J.

The International Table calorie (4.1868 J) and the 15 °C calorie differ slightly.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

The International Table BTU is exactly 1055.055 852 62 J.

Thermochemical and 39 °F BTU definitions differ by up to 0.2 %.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

1 eV = 1.602 176 634 × 10⁻¹⁹ J exactly, since the elementary charge is now fixed.

CODATA / NIST

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the joule (1 J = 1 kg·m²/s²). Thermochemical and IT calories, BTU and kWh are exact defined multiples.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the newton (1 N = 1 kg·m/s²). Gravitational units use the standard acceleration 9.806 65 m/s² exactly.

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Mechanical horsepower is exactly 550 ft·lbf/s = 745.699 871 582 270 22 W.

Metric horsepower (PS) is 735.498 75 W — about 1.4 % lower.

National Institute of Standards and Technology (US)

Metric horsepower (PS) is exactly 75 kgf·m/s = 735.498 75 W.

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the watt (1 W = 1 J/s).

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

1 bar = 100 000 Pa exactly.

Bureau International des Poids et Mesures

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

The standard atmosphere is exactly 101 325 Pa.

Bureau International des Poids et Mesures

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

1 psi = 1 lbf/in² = 6894.757 293 168 361 Pa exactly.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

The conventional millimetre of mercury is 133.322 387 415 Pa, based on mercury density 13 595.1 kg/m³ and g₀ = 9.806 65 m/s².

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Composite of a defined volume and a defined length. US and imperial gallons differ, so mpg figures are not interchangeable between them.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from mass per unit volume using the definitions above.

National Institute of Standards and Technology (US)

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the hertz (1 Hz = 1 s⁻¹), traceable to the SI second.

Bureau International des Poids et Mesures

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Derived from the newton metre; imperial torque uses the exact pound-force and foot.

National Institute of Standards and Technology (US)

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Gray and sievert are coherent SI units (J/kg). Rad and rem are exactly 0.01 Gy and 0.01 Sv; the curie is exactly 3.7 × 10¹⁰ Bq.

Bureau International des Poids et Mesures

Traceable to the candela, defined by fixing the luminous efficacy of 540 THz radiation at 683 lm/W.

Bureau International des Poids et Mesures

Traceable to the candela, defined by fixing the luminous efficacy of 540 THz radiation at 683 lm/W.

Bureau International des Poids et Mesures

Traceable to the candela, defined by fixing the luminous efficacy of 540 THz radiation at 683 lm/W.

Bureau International des Poids et Mesures

Traceable to the candela, defined by fixing the luminous efficacy of 540 THz radiation at 683 lm/W.

Bureau International des Poids et Mesures

Traceable to the candela, defined by fixing the luminous efficacy of 540 THz radiation at 683 lm/W.

Bureau International des Poids et Mesures

Derived from the lux (1 lx = 1 lm/m²); the foot-candle is 1 lm/ft².

Bureau International des Poids et Mesures

Derived from the lux (1 lx = 1 lm/m²); the foot-candle is 1 lm/ft².

Bureau International des Poids et Mesures

Derived from the lux (1 lx = 1 lm/m²); the foot-candle is 1 lm/ft².

Bureau International des Poids et Mesures

Derived from the lux (1 lx = 1 lm/m²); the foot-candle is 1 lm/ft².

Bureau International des Poids et Mesures

Based on the PostScript point of exactly 1/72 inch, which CSS also adopts for absolute lengths.

Adobe Systems / W3C

Based on the PostScript point of exactly 1/72 inch, which CSS also adopts for absolute lengths.

Adobe Systems / W3C

Based on the PostScript point of exactly 1/72 inch, which CSS also adopts for absolute lengths.

Adobe Systems / W3C

Based on the PostScript point of exactly 1/72 inch, which CSS also adopts for absolute lengths.

Adobe Systems / W3C

Based on the PostScript point of exactly 1/72 inch, which CSS also adopts for absolute lengths.

Adobe Systems / W3C

Based on the PostScript point of exactly 1/72 inch, which CSS also adopts for absolute lengths.

Adobe Systems / W3C

mg/dL and mmol/L are related through the molar mass of glucose, 180.156 g/mol (1 mmol/L ≈ 18.0156 mg/dL).

Clinical reference ranges vary by laboratory. This conversion is arithmetic only and is not medical advice.

International Federation of Clinical Chemistry

mg/dL and mmol/L are related through the molar mass of glucose, 180.156 g/mol (1 mmol/L ≈ 18.0156 mg/dL).

Clinical reference ranges vary by laboratory. This conversion is arithmetic only and is not medical advice.

International Federation of Clinical Chemistry

Only Mondopoint (ISO 9407) is defined from foot length in millimetres. US, UK and EU scales are trade conventions.

Manufacturer lasts differ. Treat cross-system results as a starting point, not a guaranteed fit.

International Organization for Standardization

Only Mondopoint (ISO 9407) is defined from foot length in millimetres. US, UK and EU scales are trade conventions.

Manufacturer lasts differ. Treat cross-system results as a starting point, not a guaranteed fit.

International Organization for Standardization

Only Mondopoint (ISO 9407) is defined from foot length in millimetres. US, UK and EU scales are trade conventions.

Manufacturer lasts differ. Treat cross-system results as a starting point, not a guaranteed fit.

International Organization for Standardization

Only Mondopoint (ISO 9407) is defined from foot length in millimetres. US, UK and EU scales are trade conventions.

Manufacturer lasts differ. Treat cross-system results as a starting point, not a guaranteed fit.

International Organization for Standardization

AWG diameters follow a geometric series between 0.4600 in (AWG 4/0) and 0.0050 in (AWG 36), as specified in ASTM B258.

ASTM International

AWG diameters follow a geometric series between 0.4600 in (AWG 4/0) and 0.0050 in (AWG 36), as specified in ASTM B258.

ASTM International

ISO 216 A/B series sizes are defined by a 1:√2 aspect ratio with A0 at one square metre. North American sizes are statutory inch dimensions.

International Organization for Standardization

ISO 216 A/B series sizes are defined by a 1:√2 aspect ratio with A0 at one square metre. North American sizes are statutory inch dimensions.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined volume divided by a defined time interval (m³/s). All listed units are exact multiples of the cubic metre per second.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity: a defined mass divided by a defined time interval (kg/s), exact via the kilogram and the international pound.

International Organization for Standardization

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, pascal-second (Pa·s = kg/(m·s)). The poise is exactly 0.1 Pa·s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, square metre per second (m²/s). The stokes is exactly 10⁻⁴ m²/s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, square metre per second (m²/s). The stokes is exactly 10⁻⁴ m²/s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, square metre per second (m²/s). The stokes is exactly 10⁻⁴ m²/s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, square metre per second (m²/s). The stokes is exactly 10⁻⁴ m²/s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, square metre per second (m²/s). The stokes is exactly 10⁻⁴ m²/s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, square metre per second (m²/s). The stokes is exactly 10⁻⁴ m²/s by CGS definition.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, watt per metre-kelvin (W/(m·K)). Imperial and calorie-based units convert exactly via the thermochemical calorie and the international BTU.

National Institute of Standards and Technology (US)

Derived quantity, joule per kilogram-kelvin (J/(kg·K)). Calorie- and BTU-based units use the thermochemical calorie (4.184 J exactly) and the International Table BTU.

National Institute of Standards and Technology (US)

Derived quantity, joule per kilogram-kelvin (J/(kg·K)). Calorie- and BTU-based units use the thermochemical calorie (4.184 J exactly) and the International Table BTU.

National Institute of Standards and Technology (US)

Derived quantity, joule per kilogram-kelvin (J/(kg·K)). Calorie- and BTU-based units use the thermochemical calorie (4.184 J exactly) and the International Table BTU.

National Institute of Standards and Technology (US)

Derived quantity, joule per kilogram-kelvin (J/(kg·K)). Calorie- and BTU-based units use the thermochemical calorie (4.184 J exactly) and the International Table BTU.

National Institute of Standards and Technology (US)

Derived quantity, joule per kilogram-kelvin (J/(kg·K)). Calorie- and BTU-based units use the thermochemical calorie (4.184 J exactly) and the International Table BTU.

National Institute of Standards and Technology (US)

Derived quantity, joule per kilogram-kelvin (J/(kg·K)). Calorie- and BTU-based units use the thermochemical calorie (4.184 J exactly) and the International Table BTU.

National Institute of Standards and Technology (US)

Derived SI unit weber (Wb = V·s). The maxwell is exactly 10⁻⁸ Wb by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit weber (Wb = V·s). The maxwell is exactly 10⁻⁸ Wb by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit weber (Wb = V·s). The maxwell is exactly 10⁻⁸ Wb by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit weber (Wb = V·s). The maxwell is exactly 10⁻⁸ Wb by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit weber (Wb = V·s). The maxwell is exactly 10⁻⁸ Wb by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit weber (Wb = V·s). The maxwell is exactly 10⁻⁸ Wb by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived SI unit tesla (T = Wb/m²). The gauss is exactly 10⁻⁴ T by CGS-Gaussian definition.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived from the mole, defined by fixing the Avogadro constant at 6.022 140 76 × 10²³ mol⁻¹, divided by a defined volume.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures

Derived SI unit katal (kat = mol/s). The enzyme unit (U) is exactly 1 µmol/min = 1/60 µkat.

Bureau International des Poids et Mesures