How Many Seconds Are in a Year?

A year has 31,536,000 seconds (31,622,400 in a leap year; 31,556,952 on average). See the math and every year.

Last updated

A year has 31,536,000 seconds (365 × 24 × 60 × 60), or 31,622,400 seconds in a leap year. The average Gregorian year is 31,556,952 seconds.

31,556,952 seconds

1 year = 31,556,952 seconds

The same amount in every unit
UnitAmount
Milliseconds31,556,952,000
Seconds31,556,952
Minutes525,949.2
Hours8,765.82
Days365.2425
Weeks52.1775
Months12
Decades0.1
Centuries0.01

A year is 365.2425 days on average (Gregorian calendar: 97 leap years every 400 years). A common year has 365 days (52 weeks and 1 day); a leap year has 366 (52 weeks and 2 days).

How it’s calculated

Every unit is converted through seconds: 1 minute = 60 s, 1 hour = 3,600 s, 1 day = 86,400 s, 1 week = 604,800 s. Months and years use the Gregorian average: 1 year = 365.2425 days = 31,556,952 s, 1 month = 1/12 year = 2,629,746 s.

Worked example with your numbers

  1. 1 year × 31,556,952 seconds per year = 31,556,952 seconds.
  2. 31,556,952 seconds ÷ 1 seconds per second = 31,556,952 seconds.

Quick answer

A year has 31,536,000 seconds (365 × 24 × 60 × 60), or 31,622,400 seconds in a leap year.

Common year
31,536,000 s
Leap year
31,622,400 s
Day
86,400 s
Hour
3,600 s

2026 has 365 days — 52 weeks and 1 day — and 53 ISO weeks. Today is in ISO week 46. It has 261 weekdays (Monday–Friday).

Days, weeks, hours and seconds by year
Year Days Weeks ISO weeks Hours Seconds
2025 365 52 + 1 day 52 8,760 31,536,000
2026 365 52 + 1 day 53 8,760 31,536,000
2027 365 52 + 1 day 52 8,760 31,536,000
2028 (leap) 366 52 + 2 days 52 8,784 31,622,400
2029 365 52 + 1 day 52 8,760 31,536,000
2030 365 52 + 1 day 52 8,760 31,536,000
2031 365 52 + 1 day 52 8,760 31,536,000
2032 (leap) 366 52 + 2 days 53 8,784 31,622,400

A common year is 365 days (52 weeks + 1 day, 8,760 hours); a leap year is 366 days (52 weeks + 2 days, 8,784 hours). Averaged over the 400-year Gregorian cycle a year is 365.2425 days = 52.1775 weeks = 8,765.82 hours. ISO 8601 numbers weeks Monday–Sunday; a year has 53 ISO weeks when it starts on a Thursday (or on a Wednesday in a leap year).

How it works

Leap seconds, occasionally added to keep clocks in step with the Earth’s rotation, are left out — they are rare and irregular.

Frequently asked questions

How many seconds are in a day?

86,400 (24 × 60 × 60).

How many seconds are in an hour?

3,600 (60 × 60).