A year has 12 months: seven with 31 days, four with 30 days and February with 28 days (29 in a leap year) — 365 or 366 days in all.
12 months
1 year = 12 months
| Unit | Amount |
|---|---|
| Milliseconds | 31,556,952,000 |
| Seconds | 31,556,952 |
| Minutes | 525,949.2 |
| Hours | 8,765.82 |
| Days | 365.2425 |
| Weeks | 52.1775 |
| Months | 12 |
| Decades | 0.1 |
| Centuries | 0.01 |
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). A month is 30.436875 days on average (a year ÷ 12). Calendar months have 28 to 31 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 year × 31,556,952 seconds per year = 31,556,952 seconds.
- 31,556,952 seconds ÷ 2,629,746 seconds per month = 12 months.
Quick answer
A year has 12 months: seven with 31 days, four with 30 days and February with 28 days (29 in a leap year) — 365 or 366 days in all.
- Months in a year
- 12
- Months in a decade
- 120
- Weeks in a month
- ≈ 4.35
- Days in a month
- 28–31
| Month | Days | Weeks | Hours | Weekdays |
|---|---|---|---|---|
| January | 31 | 4 weeks + 3 days | 744 | 22 |
| February | 28 | 4 weeks + 0 days | 672 | 20 |
| March | 31 | 4 weeks + 3 days | 744 | 22 |
| April | 30 | 4 weeks + 2 days | 720 | 22 |
| May | 31 | 4 weeks + 3 days | 744 | 21 |
| June | 30 | 4 weeks + 2 days | 720 | 22 |
| July | 31 | 4 weeks + 3 days | 744 | 23 |
| August | 31 | 4 weeks + 3 days | 744 | 21 |
| September | 30 | 4 weeks + 2 days | 720 | 22 |
| October | 31 | 4 weeks + 3 days | 744 | 22 |
| November | 30 | 4 weeks + 2 days | 720 | 21 |
| December | 31 | 4 weeks + 3 days | 744 | 23 |
Average month (365.2425 ÷ 12): 30.436875 days = 4.348 weeks = 730.485 hours. “Thirty days hath September, April, June and November; all the rest have thirty-one, except February” — 28 days, 29 in a leap year.
How it works
A year is also 4 quarters of 3 months each, and 2 halves of 6 months.
Frequently asked questions
How many months are in two years?
24 months.
How many months is a year and a half?
18 months.