Tropical Year to Sidereal Year Converter

Time Converter

21 units available

Decimals:

From

To

0.999961

1 trop yr = 0.999961 sid yr

Formula:

sid yr = trop yr × 0.9999612053

With your value: 1 trop yr = 0.99996121 sid yr

How big is that?

Everyday references on a logarithmic scale, all expressed in tropical year so you can sanity-check the result.

Minute (1/5.3e+5 your value)0.00000190 trop yr

Working day (1/1.1e+3 your value)0.000913 trop yr

Day (1/3.7e+2 your value)0.00274 trop yr

Week (1/52 your value)0.0192 trop yr

Your value1.00 trop yr

Year (1.0× your value)1.00 trop yr

Other Tropical Year to Sidereal Year conversions

2 trop yr to sid yr 3 trop yr to sid yr 4 trop yr to sid yr 5 trop yr to sid yr 6 trop yr to sid yr 7 trop yr to sid yr 8 trop yr to sid yr

Tropical Year to Sidereal Year Conversion Table

Tropical Year (trop yr)	Sidereal Year (sid yr)
0.5	0.499981
1	0.999961
2	1.999922
5	4.999806
10	9.999612
15	14.999418
20	19.999224
25	24.99903
50	49.99806
100	99.996121
250	249.990301
500	499.980603
1000	999.961205

Sidereal Year to Tropical Year Conversion Table

Sidereal Year (sid yr)	Tropical Year (trop yr)
0.5	0.500019
1	1.000039
2	2.000078
5	5.000194
10	10.000388
15	15.000582
20	20.000776
25	25.00097
50	50.00194
100	100.00388
250	250.009699
500	500.019398
1000	1,000.038796

Where these values come from

Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.

Tropical Year (trop yr)

Time

SI definition

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

Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)

Bureau International des Poids et Mesures · Reviewed 2026-07-01

Sidereal Year (sid yr)

Time

SI definition

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

Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)

Bureau International des Poids et Mesures · Reviewed 2026-07-01

How to Convert Tropical Year to Sidereal Year

To convert from Tropical Year (trop yr) to Sidereal Year (sid yr), multiply the value by 0.9999612053.

Formula: sid yr = trop yr × 0.9999612053

Reverse: trop yr = sid yr × 1.0000387962

Step-by-Step Example

Start with your value in Tropical Year. For example: 5 trop yr
Multiply by the conversion factor: 5 x 0.9999612053
The result is: 4.999806 sid yr

About Tropical Year

The tropical year (trop yr) is a unit of time. One tropical year equals 3.155693 × 10^+7 seconds. UnitConvertLab converts it against every other time unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.

Common uses: time calculations, engineering and science, education.

About Sidereal Year

The sidereal year (sid yr) is a unit of time. One sidereal year equals 3.155815 × 10^+7 seconds. UnitConvertLab converts it against every other time unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.

Common uses: time calculations, engineering and science, education.

Frequently Asked Questions

How many Sidereal Year are in 1 Tropical Year?

There are exactly 0.9999612053 Sidereal Year in 1 Tropical Year. This means the conversion factor from Tropical Year to Sidereal Year is 0.9999612053.

What is the formula to convert Tropical Year to Sidereal Year?

The formula to convert Tropical Year to Sidereal Year is: sid yr = trop yr × 0.9999612053. For example, to convert 10 Tropical Year to Sidereal Year, you would multiply 10 by 0.9999612053.

What is a Tropical Year?