Weeks to days
Multiply weeks by 7 to get days.
8 wk = 56 d
How to convert weeks to days
The day is exactly 24 hours (86 400 seconds). The week is exactly 7 days.
Worked example — 8 wk: 8 × 7 = 56 d.
Weeks to days table
| Weeks | Days |
|---|---|
| 1 wk | 7 d |
| 2 wk | 14 d |
| 4 wk | 28 d |
| 6 wk | 42 d |
| 8 wk | 56 d |
| 12 wk | 84 d |
| 26 wk | 182 d |
| 40 wk | 280 d |
| 52 wk | 364 d |
Reverse and related
About weeks and days
Week (wk)
1 wk = 7 dDefinition. Exactly 7 days
History and origin
The week is a seven-day cycle with ancient roots in Babylonian and Jewish tradition, tied to the seven classical planets and to religious observance. Unlike other time units it has no astronomical basis.
Current use
Weeks organise schedules and are used to count the length of pregnancies and projects.
Source: BIPM SI Brochure (2019); the second is defined by the caesium-133 transition
Day (d)
1 d = 0.142857 wkDefinition. Exactly 24 hours (86 400 seconds)
History and origin
The day is based on one rotation of the Earth and is fixed for timekeeping at exactly 24 hours, or 86 400 seconds. The natural day varies slightly, so a mean value is used.
Current use
Days are the basic unit of the calendar and of everyday durations.
Source: BIPM SI Brochure (2019); the second is defined by the caesium-133 transition
Where people use this
Weeks: schedules, pregnancy and projects. Days: calendars, durations. 40 weeks (full-term pregnancy) is 280 days.
Every value is carried to full double precision; the display is rounded.
Both units are defined in BIPM SI Brochure (2019); the second is defined by the caesium-133 transition.
Questions people ask
How many days in a week?
One week is exactly 7 days.
How many days is 40 weeks?
40 weeks (a full-term pregnancy) is 280 days.
How many days is 4 weeks?
4 weeks is 28 days.