This converter turns years into seconds instantly, using the exact factor 1 year = 31557600 seconds. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
The Julian year of 365.25 days used in astronomy and engineering. The SI base unit of time, defined by caesium-133 atomic transitions.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
years- The amount you are converting, measured in years
31557600- The exact number of seconds in one year
seconds- The converted result
How it works, step by step
- Enter the number of years you want to convert.
- The value is multiplied by 31557600, the exact conversion factor.
- The result is displayed in seconds, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 years
Multiply 5 by 31557600. That gives 157,788,000 seconds. A quick sanity check: one year is larger than one second, so the number should get bigger — and it does.
Converting 72 years
72 × 31557600 = 2,272,147,200 seconds. Working backwards, 2,272,147,200 ÷ 31557600 returns 72 years, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many seconds are in one year?
Exactly 31557600. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert years to seconds?
Seconds = years × 31557600. To reverse it, divide instead: years = seconds ÷ 31557600, which is the same as multiplying by 3.168808781e-08.
Is the year bigger than the second?
Yes. One year equals 3.15576e+07 seconds, so it is the larger unit.
Why does my answer differ slightly from other years to seconds converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a year?
The Julian year of 365.25 days used in astronomy and engineering.
What is a second?
The SI base unit of time, defined by caesium-133 atomic transitions.
Years to seconds reference table
| Years | Seconds |
|---|---|
| 0.5 yr | 15,778,800 s |
| 1 yr | 31,557,600 s |
| 2 yr | 63,115,200 s |
| 3 yr | 94,672,800 s |
| 5 yr | 157,788,000 s |
| 10 yr | 315,576,000 s |
| 15 yr | 473,364,000 s |
| 20 yr | 631,152,000 s |
| 25 yr | 788,940,000 s |
| 50 yr | 1,577,880,000 s |
| 75 yr | 2,366,820,000 s |
| 100 yr | 3,155,760,000 s |
| 250 yr | 7,889,400,000 s |
| 500 yr | 15,778,800,000 s |
| 1000 yr | 31,557,600,000 s |
Exact factor: 1 year = 31557600 seconds. Values rounded for display.