Hours pile up into days in two different ways. Elapsed time, such as a 100-hour battery life, a 72-hour deadline or the time left before a launch, counts 24-hour calendar days. Work time, such as a 45-hour project estimate or accrued leave, is usually counted in 8-hour workdays. This converter does both and shows the result as decimal days and as days plus leftover hours.
How to use the hours to days converter
- Enter the number of Hours.
- Choose how to Count days: 24-hour calendar days or 8-hour workdays.
- Read the decimal days on the tape with the days-and-hours breakdown underneath.
- The rows below show weeks (or 5-day work weeks), total minutes and the same hours counted the other way.
Hours to days formula
where hours per day is 24 for calendar days or 8 for workdays. For a days-and-hours answer, use division with a remainder:
Worked examples
Calendar days: 100 hours ÷ 24 = 4.1667 days; 4 × 24 = 96, leaving 4 hours, so 4 days 4 hours (0.595 weeks).
Workdays: a project estimated at 45 hours ÷ 8 = 5.625 workdays, or 5 workdays and 5 hours. That is 1.125 five-day work weeks.
The same 100 hours could be 4.2 days of continuous time or 12.5 working days, so always say which kind of day you mean.
Hours to days table
| Hours | Calendar days | Days and hours | 8-hour workdays |
|---|---|---|---|
| 6 | 0.25 | 6 hours | 0.75 |
| 8 | 0.3333 | 8 hours | 1 |
| 12 | 0.5 | 12 hours | 1.5 |
| 24 | 1 | 1 day | 3 |
| 36 | 1.5 | 1 day 12 hours | 4.5 |
| 40 | 1.6667 | 1 day 16 hours | 5 |
| 48 | 2 | 2 days | 6 |
| 60 | 2.5 | 2 days 12 hours | 7.5 |
| 72 | 3 | 3 days | 9 |
| 96 | 4 | 4 days | 12 |
| 100 | 4.1667 | 4 days 4 hours | 12.5 |
| 120 | 5 | 5 days | 15 |
| 168 | 7 | 7 days (1 week) | 21 |
| 240 | 10 | 10 days | 30 |
| 720 | 30 | 30 days | 90 |
| 8,760 | 365 | 365 days (1 year) | 1,095 |
Calendar days or workdays?
Use calendar days for anything that runs around the clock: shipping and delivery windows, medication schedules, equipment run time, battery life, parking, rentals and countdowns. A “72-hour return window” closes three calendar days after it opens.
Use workdays for effort: project planning, paid time off, overtime banks and staffing. If a job takes 45 hours of labor, one person working 8-hour days needs about 5.6 working days, which stretches across more than a calendar week once weekends are included. Some employers use 7.5-hour or 10-hour days; divide by that length instead.
Quick facts
- 1 day = 24 hours = 1,440 minutes = 86,400 seconds
- 1 week = 168 hours
- 1 common year = 8,760 hours; 1 leap year = 8,784 hours
- 1 full-time work year (40 h × 52 weeks) = 2,080 hours
To count calendar dates that fall a given number of days later, use the date calculator. For shift totals and weekly hours, try the work hours calculator, and for shorter spans, the hours to minutes converter.
Frequently asked questions
How do I convert hours to days?
Divide by 24 for calendar days: 100 hours ÷ 24 = 4.1667 days, which is 4 days and 4 hours. For working time, divide by the length of a workday instead, usually 8 hours.
How many days is 72 hours?
Exactly 3 days. Likewise 48 hours is 2 days and 168 hours is 1 week.
How many workdays is 40 hours?
Five 8-hour workdays, or one standard full-time work week. In calendar terms, 40 hours is 1 day and 16 hours.
How many hours are in a year?
A 365-day year has 8,760 hours and a leap year 8,784. A full-time employee working 40 hours a week for 52 weeks puts in 2,080 hours.