Year (365 days) to Sidereal Year Converter

Time Converter

21 units available

Decimals:

From

To

0.999298

1 yr = 0.999298 sid yr

Formula:

sid yr = yr × 0.9992981368

With your value: 1 yr = 0.99929814 sid yr

How big is that?

Everyday references on a logarithmic scale, all expressed in year (365 days) so you can sanity-check the result.

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

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

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

Week (1/52 your value)0.0192 yr

Your value1.00 yr

Year (1.0× your value)1.00 yr

Other Year (365 days) to Sidereal Year conversions

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

Year (365 days) to Sidereal Year Conversion Table

Year (365 days) (yr)	Sidereal Year (sid yr)
0.5	0.499649
1	0.999298
2	1.998596
5	4.996491
10	9.992981
15	14.989472
20	19.985963
25	24.982453
50	49.964907
100	99.929814
250	249.824534
500	499.649068
1000	999.298137

Sidereal Year to Year (365 days) Conversion Table

Sidereal Year (sid yr)	Year (365 days) (yr)
0.5	0.500351
1	1.000702
2	2.001405
5	5.003512
10	10.007024
15	15.010535
20	20.014047
25	25.017559
50	50.035118
100	100.070236
250	250.175589
500	500.351178
1000	1,000.702356

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.

Year (365 days) (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 Year (365 days) to Sidereal Year

To convert from Year (365 days) (yr) to Sidereal Year (sid yr), multiply the value by 0.9992981368.

Formula: sid yr = yr × 0.9992981368

Reverse: yr = sid yr × 1.0007023562

Step-by-Step Example

Start with your value in Year (365 days). For example: 5 yr
Multiply by the conversion factor: 5 x 0.9992981368
The result is: 4.996491 sid yr

About Year (365 days)

The year (365 days) (yr) is a unit of time. One year (365 days) equals 3.153600 × 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 Year (365 days)?

There are exactly 0.9992981368 Sidereal Year in 1 Year (365 days). This means the conversion factor from Year (365 days) to Sidereal Year is 0.9992981368.

What is the formula to convert Year (365 days) to Sidereal Year?

The formula to convert Year (365 days) to Sidereal Year is: sid yr = yr × 0.9992981368. For example, to convert 10 Year (365 days) to Sidereal Year, you would multiply 10 by 0.9992981368.

What is a Year (365 days)?