Days to Weeks
Type a value in either box to convert between days and weeks. The factor is 0.142857.
| Days | Weeks |
|---|---|
| 1 day | 0.142857 wk |
| 2 day | 0.285714 wk |
| 3 day | 0.428571 wk |
| 5 day | 0.714286 wk |
| 10 day | 1.428571 wk |
| 25 day | 3.571429 wk |
| 50 day | 7.142857 wk |
| 100 day | 14.285714 wk |
How to use
- Enter a value in the Days field.
- The Weeks figure appears immediately — no button to press.
- Typing in the Weeks field converts back to Days the same way.
- Use the reference table for the values that come up most often.
Days to Weeks formula
Converting days to weeks is a single multiplication by 0.142857143.
wk = day × 0.142857143
Put another way, one day is exactly 1/7 of a week.
Why this factor: the day and the week are both defined against the second, so dividing one definition by the other gives 0.142857143 directly. Both definitions are set out in full below.
To go the other way, divide by 0.142857143 — or use the Weeks to Days converter, which is the same calculation reversed.
Worked example
Start with 15 day. Multiply by 0.142857143 to get 2.142857 wk.
15 day × 0.142857143 = 2.142857 wk
The converter above does this for any value you type, in either direction.
What is a day?
A day is 24 hours, one nominal rotation of the Earth.
Definition: Exactly 86,400 seconds by convention. The Earth's actual rotation drifts slightly, which is what leap seconds correct.
Where it is used: Calendars, project schedules, hotel and rental periods, and interest accrual.
What is a week?
A week is seven days, the standard unit of work and project planning.
Definition: Exactly 604,800 seconds.
Where it is used: Sprint and project planning, payroll periods, pregnancy tracking, and lead times.
Days vs Weeks
The day and the week belong to the same family of units, so converting between them is usually a matter of shifting a decimal point or applying a small whole-number factor.
Frequently asked questions
How many weeks are in a day?
One day equals 0.142857143 weeks.
What is the formula to convert days to weeks?
Multiply the number of days by 0.142857143. To reverse it, divide by 0.142857143 instead.
How do I convert weeks back to days?
Divide by 0.142857143, which is the same as multiplying by 7.
How many weeks are in 10 days?
10 day works out to 1.428571 wk.
How is the day defined?
Exactly 86,400 seconds by convention. The Earth's actual rotation drifts slightly, which is what leap seconds correct.