How it's calculated
weeks = days ÷ 7 (reverse: days = weeks × 7)
7 days per week.
Common values
| Days | Weeks |
|---|---|
| 7 days | 1 week |
| 14 days | 2 weeks |
| 30 days | 4 weeks 2 days |
| 90 days | 12 weeks 6 days |
| 280 days | 40 weeks |
Common questions
How do I convert days to weeks?
Divide the number of days by 7. So 21 days is exactly 3 weeks.
Why is a full-term pregnancy 40 weeks?
Pregnancy is counted from the last menstrual period, and 40 weeks works out to 280 days.