How do I convert hours to days?
Type a value in either box, and the answer shows it in the other unit as you type.
- Days (d)
- 0.041667
1 h = 0.041667 d (0 d 1 h).
- Days and hours
- 0 d 1 h
Days (d): 0.041667. 1 h = 0.041667 d (0 d 1 h).
Days (d) by hours (h)
How to calculate
Converts hours (h) to days (d) and back, with the exact unit definitions.
Example with the default inputs (Hours (h) 1): 1 h = 0.041667 d (0 d 1 h).
Formula: d = h × 0.0416666666667 (the same as h ÷ 24)
- 1 hour = 0.0416666666667 days, from the exact definitions in NIST SP 811.
- Exact on the typed decimals: at most 6 decimal places (6 significant digits below 0.0001), rounded half up.
- Days and hours use the box you typed; hours round half up to 0.01, and 24.00 carries.
Worked examples
Each example is checked against the calculator on every build.
- Hours (h) 24 gives Days (d) 1.Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8
- Hours (h) 36 gives Days (d) 1.5.Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8
- Days (d) 1.5 gives Hours (h) 36.Source: Exact unit definitions in NIST SP 811 (2008), Appendix B.8
Other questions people ask
How many days are in a hour?
1 hour is 0.041667 days, from the exact unit definitions (NIST SP 811).
How do I convert hours to days?
Multiply by 0.041667: d = h × 0.0416666666667 (the same as h ÷ 24). For example, 1 h × 0.041667 = 0.041667 d.
How do I convert days back to hours?
Multiply by 24, or type the days into the second box and the converter works it out. 1 day is 24 hours.
How many days is 100 hours?
100 ÷ 24 = 4.166667 days, which is 4 whole days and 4 hours.
How many hours are in a week?
168: 7 days × 24 hours. 168 hours in the converter gives 7 days.
Does a day always have 24 hours?
Here it does: a day is 86,400 seconds, 24 hours (NIST SP 811). A clock day with a daylight saving change has 23 or 25 hours, which this converter does not count.