Hours Calculator
Find the hours between a start and end time, minus your break, as hours and minutes and as decimal hours. Advanced adds a weekly timesheet, rounding, overtime and pay.
Type it any way: 9, 9am, 0930, 9:30 pm or 21:30. An end time earlier than the start means the shift ran past midnight.
Each day has its own unpaid break in the timesheet below.
Write 1:30, 1:30:15, 1.5 (hours), 90 min or 1h 30m.
Day-by-day breakdown
| Day | In – out | Break | Hours | Decimal | Regular | Overtime | Pay |
|---|
How your hours are worked out
Hours = end time − start time − break.
- 1
Clock in to out
17:30 − 09:00= 8:30
- 2
Take off the break
8:30 − 0:30= 8:00
- 3
Into decimal hours
8 h + 0 min ÷ 60= 8.00 h
- 4
In minutes
8 × 60 + 0= 480 min
Read more: the formula, worked examples, overtime and rounding
To find the hours worked, take the start time away from the end time, then take off any unpaid break. If the end time is earlier than the start, the shift ran past midnight, so add 24 hours. To turn hours and minutes into decimal hours for payroll, divide the minutes by 60.
The formula
hours worked = end time − start time − break
(add 24 hours if the end is earlier than the start)
decimal hours = hours + minutes ÷ 60
overtime = hours over the daily limit, then regular hours over the weekly limit
pay = regular hours × rate + overtime hours × rate × overtime multiplier
Worked example
You start at 09:00 and finish at 17:30 with a 30-minute break. 17:30 − 09:00 = 8 hours 30 minutes. Take off the 30-minute break: 8:30 − 0:30 = 8:00, which is 8.00 decimal hours or 480 minutes.
A night shift from 22:00 to 06:00 with a 45-minute break: 06:00 is earlier than 22:00, so add 24 hours. 30:00 − 22:00 = 8:00, minus 0:45 = 7:15, or 7 + 15 ÷ 60 = 7.25 hours.
Weekly timesheet with overtime
Monday to Friday, 08:30 to 17:30 with 30 minutes for lunch, is 8:30 a day and 42:30 for the week. With overtime after 40 hours a week, 40:00 is regular and 2:30 (2.5 hours) is overtime. At 20 an hour and time and a half: 40 × 20 = 800, plus 2.5 × 20 × 1.5 = 75, so the week pays 875.
When you set a daily and a weekly limit, daily overtime is counted first. Only regular hours count towards the weekly limit, so the same hour is never paid as overtime twice. Double time (if you set it) covers hours past its own daily limit.
Minutes to decimal hours
| Minutes | 5 | 6 | 10 | 12 | 15 | 20 | 30 | 45 |
|---|---|---|---|---|---|---|---|---|
| Decimal hours | 0.08 | 0.1 | 0.17 | 0.2 | 0.25 | 0.33 | 0.5 | 0.75 |
Rounding time cards
Many employers round clock times to the nearest 5, 6 or 15 minutes. With 15-minute rounding "to the nearest", 7 minutes or less rounds down and 8 minutes or more rounds up, so 08:53 becomes 09:00 and 17:07 becomes 17:00. Six minutes is a tenth of an hour, which is why payroll often uses it. In the United States, the Department of Labor allows rounding to the nearest 5, 6 or 15 minutes only if, over time, it doesn't leave workers underpaid (29 CFR 785.48), so "always down" is risky. Rules elsewhere vary.
Overtime rules depend on your country, state and contract. As examples: US federal law (FLSA) pays time and a half after 40 hours in a work week; California also pays overtime after 8 hours in a day and double time after 12. Enter the limits that apply to you. Checked 10 October 2026.
Common questions
How do I calculate hours worked?
Take the start time away from the end time, then take off your break. 09:00 to 17:30 is 8 hours 30 minutes, and minus a 30-minute break that is 8:00, or 8.00 decimal hours. If the shift runs past midnight, 24 hours are added to the end time.
How do I convert minutes to decimal hours?
Divide the minutes by 60 and add them to the hours. 7 hours 15 minutes is 7 + 15 ÷ 60 = 7.25 hours. The Read more section has a table of common minutes and their decimal values, handy for time cards and payroll.
How is overtime calculated?
Hours over your daily limit count first, then regular hours over the weekly limit. With overtime after 40 hours a week, a 42:30 week gives 2.5 overtime hours. At 20 an hour and time and a half, that week pays 800 + 75 = 875. Enter the limits that apply to you.
How do I work out hours for an overnight shift?
When the end time is earlier than the start, the shift crossed midnight, so 24 hours are added. A shift from 22:00 to 06:00 with a 45-minute break is 8 hours minus 0:45, which is 7:15, or 7.25 decimal hours.
How does time card rounding work?
Many employers round clock times to the nearest 5, 6 or 15 minutes. With 15-minute rounding to the nearest, 7 minutes or less rounds down and 8 or more rounds up, so 08:53 becomes 09:00. In the United States, rounding is allowed only if it doesn't leave workers underpaid over time.
Is overtime paid after 8 hours a day?
It depends on where you work and your contract. US federal law pays time and a half after 40 hours in a work week, while California also pays overtime after 8 hours in a day and double time after 12. Rules elsewhere vary, so set the limits that apply to you.
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