1 hour = 0.041666667 d
1 h = 0.0416667 d · type math like (12*4)+6.5
Hours to days helps put long durations into perspective, such as total hours on a project, battery life ratings or flight time logs.
Device battery life is often given in hours. A smartwatch with 336 hours of standby lasts 14 days, and a phone rated for 40 hours lasts 1.67 days. Converting makes it easier to compare devices.
Volunteer and work hour totals are often converted into days. 2,080 hours, a standard full-time work year in the US, is 86.7 calendar days or 260 eight-hour workdays.
Flight logs and pilot training count hours. A commercial pilot license in the US requires 250 flight hours, which is 10.4 calendar days of continuous flying.
Server uptime is measured in hours too. 8,760 hours is one year, and 99.9% uptime allows 8.76 hours of downtime per year.
Shipping and logistics companies quote transit times in hours for express services and days for standard ones. A 96 hour delivery window is 4 days, while a 120 hour window is 5 days. When a package says it will arrive within 72 hours, that is 3 calendar days, not 3 business days, so weekends count.
Medical and lab work also converts hours to days. A blood culture is typically incubated for 120 hours, which is 5 days, before being reported as negative. Quarantine periods are often written in days but tracked in hours: a 240 hour period is 10 days.
Long-haul trucking regulations in the US limit drivers to 70 hours of on-duty time over 8 days. Converted, 70 hours is 2.92 days of continuous time, but it is spread across the 8-day period with mandatory rest breaks.
Gaming and streaming platforms track play time in hours. A player with 1,200 hours in a game has spent the equivalent of 50 full days playing. Converting large hour totals into days makes them easier to picture, which is why platforms sometimes show both.
Astronomy also uses this. Jupiter's day is about 9.9 hours, so it rotates about 2.4 times in one Earth day.
Time-lapse and data logging projects often run for set hours. A 500 hour test is 20.8 days.
To sanity-check, every 24 hours makes one day, so 48 hours is 2 days and 168 hours is a full week. If your result for 30 hours is 3 days, you divided by 10 instead of 24; the correct answer is 1.25 days, or 1 day 6 hours. Always state whether you mean calendar days or working days, because a 40 hour task can be 1.67 calendar days or 5 working days.
d = h × 0.04166666667
Reverse: 1 d = 24 h.
Convert 100 hours to days.
Answer: 100 h = 4.17 days = 4 d 4 h.
| h | d |
|---|---|
| ¼ h | 0.010416667 d |
| ½ h | 0.020833333 d |
| ¾ h | 0.03125 d |
| 1 h | 0.041666667 d |
| 2 h | 0.083333333 d |
| 3 h | 0.125 d |
| 4 h | 0.16666667 d |
| 5 h | 0.20833333 d |
| 6 h | 0.25 d |
| 7 h | 0.29166667 d |
| 8 h | 0.33333333 d |
| 9 h | 0.375 d |
| 10 h | 0.41666667 d |
| 11 h | 0.45833333 d |
| 12 h | 0.5 d |
| 13 h | 0.54166667 d |
| h | d |
|---|---|
| 14 h | 0.58333333 d |
| 15 h | 0.625 d |
| 16 h | 0.66666667 d |
| 17 h | 0.70833333 d |
| 18 h | 0.75 d |
| 19 h | 0.79166667 d |
| 20 h | 0.83333333 d |
| 25 h | 1.0416667 d |
| 30 h | 1.25 d |
| 40 h | 1.6666667 d |
| 50 h | 2.0833333 d |
| 75 h | 3.125 d |
| 100 h | 4.1666667 d |
| 250 h | 10.416667 d |
| 500 h | 20.833333 d |
| 1 000 h | 41.666667 d |
A 100 hour battery lasts 4 days 4 hours.
500 work hours is 20.8 calendar days, or 62.5 eight-hour workdays.
A 72 hour fast is 3 days.
Divide by 24 for calendar days, by 8 for workdays.
0.17 day × 24 = 4 h.
50 hours is 2.08 days. Rounding to 2 days misses 2 hours.
An hour is exactly 3,600 seconds, or 60 minutes.
Origin. Ancient Egyptians split day and night into 12 parts each. The fixed 60-minute hour spread with mechanical clocks in 14th century Europe.
Used today. Device runtimes, logs and billing.
A day is 24 hours, or 86,400 seconds.
Origin. Based on Earth's rotation relative to the Sun.
Used today. Calendar time.
41.67 days.
7 days.
1.5 days.
5 eight-hour days.