How many weeks are in a month?
4.35 weeks on average — every month is 4 weeks plus 0 to 3 days. Only February (in a common year) is exactly 4 weeks.
Every month of 2026
| Month | Days | Weeks (exact) | Weeks + days | Weekdays | ISO weeks touched |
|---|---|---|---|---|---|
| January | 31 | 4.43 | 4 weeks + 3 days | 22 | 1–5 |
| February | 28 | 4.00 | 4 weeks + 0 days | 20 | 5–9 |
| March | 31 | 4.43 | 4 weeks + 3 days | 22 | 9–14 |
| April | 30 | 4.29 | 4 weeks + 2 days | 22 | 14–18 |
| May | 31 | 4.43 | 4 weeks + 3 days | 21 | 18–22 |
| June | 30 | 4.29 | 4 weeks + 2 days | 22 | 23–27 |
| July | 31 | 4.43 | 4 weeks + 3 days | 23 | 27–31 |
| August | 31 | 4.43 | 4 weeks + 3 days | 21 | 31–36 |
| September | 30 | 4.29 | 4 weeks + 2 days | 22 | 36–40 |
| October | 31 | 4.43 | 4 weeks + 3 days | 22 | 40–44 |
| November | 30 | 4.29 | 4 weeks + 2 days | 21 | 44–49 |
| December | 31 | 4.43 | 4 weeks + 3 days | 23 | 49–53 |
Method
Weeks = days in the month ÷ 7. The average 4.35 is 365.25 ÷ 7 ÷ 12. Weekdays are Monday–Friday counted by date. "ISO weeks touched" is the first and last ISO week number that has at least one day in the month.