How Many Seconds Are in a Year?
A year has 31,536,000 seconds in a common year (365 days), or 31,622,400 seconds in a leap year (366 days). The average Gregorian year is 31,556,952 seconds (365.2425 days). Every figure here is just days × 86,400 — the number of seconds in a day. Last updated 2026-06-20.
Seconds in a specific year
Enter a year — it works out whether that year is a leap year and counts the exact seconds, entirely in your browser.
2026 is a common year (365 days) = 31,536,000 seconds (525,600 minutes, 8,760 hours).
Seconds in a year by year length
| Year length | Seconds |
|---|---|
| Common year (365 days) | 31,536,000 seconds |
| Leap year (366 days) | 31,622,400 seconds |
| Average Gregorian year (365.2425 days) | 31,556,952 seconds |
| Julian year (365.25 days, astronomy) | 31,557,600 seconds |
How to calculate seconds in a year
Every day has 24 × 60 × 60 = 86,400 seconds. So the seconds in a year is simply the number of days in that year multiplied by 86,400:
seconds = days in year × 86,400
A common 365-day year is 365 × 86,400 = 31,536,000 seconds; a 366-day leap year is 366 × 86,400 = 31,622,400 seconds — exactly one day (86,400 seconds) more. Over the long run the calendar averages 365.2425 days per year, which is 31,556,952 seconds.
Seconds in a second, minute, hour, day, week, month and year
The seconds in every common time period (each is just its length in days × 86,400):
| Period | Days | Seconds |
|---|---|---|
| 1 minute | 0.0007 | 60 |
| 1 hour | 0.0417 | 3,600 |
| 1 day | 1 | 86,400 |
| 1 week | 7 | 604,800 |
| 1 month (30 days) | 30 | 2,592,000 |
| 1 month (average) | 30.4369 | 2,629,746 |
| 1 year (365 days) | 365 | 31,536,000 |
| 1 year (366 days, leap) | 366 | 31,622,400 |
| 1 decade (10 average years) | 3,652.425 | 315,569,520 |
Handy reference: there are 86,400 seconds in a day, 3,600 in an hour, 604,800 in a week, and roughly 31.5 million in a year.
Why a year is not a fixed number of seconds
A calendar year is usually 365 days, but every leap year gains a day to keep the calendar in step with Earth's orbit (about 365.2425 days). Leap years are those divisible by 4 — except century years, which are leap years only when divisible by 400 (so 2000 was a leap year but 1900 was not). That extra day adds 86,400 seconds, which is why a year has either 31,536,000 or 31,622,400 seconds. For an exact answer, count the days in that specific year — which is what the calculator above does. The same is true of a month, whose length varies from 28 to 31 days. Our time unit converter deliberately leaves "year" out of its fixed-factor list.
Frequently asked questions
- How many seconds are in a year?
- A common (non-leap) year has 31,536,000 seconds — that is 365 days × 86,400 seconds per day. A leap year has 31,622,400 seconds (366 days). The average Gregorian year is 31,556,952 seconds (365.2425 days).
- How many seconds are in a leap year?
- A leap year has 366 days, so 366 × 86,400 = 31,622,400 seconds — exactly 86,400 seconds (one day) more than a common year.
- How many seconds are in a day?
- A day has 24 × 60 × 60 = 86,400 seconds (1,440 minutes, 24 hours). This is the building block for every figure on this page.
- How do you calculate the number of seconds in a year?
- Multiply the number of days in the year by 86,400 (the seconds in a day). A 365-day year = 365 × 86,400 = 31,536,000 seconds; a 366-day leap year = 366 × 86,400 = 31,622,400 seconds.
- How many seconds are in the average year?
- The average Gregorian calendar year is 365.2425 days, which is 31,556,952 seconds — about 31.56 million. This average accounts for the leap-year pattern (a leap year every 4 years, except century years not divisible by 400) and is used for long-span rate calculations.