Quick answer: subtract the start from the end and take off breaks: 08:45 to 17:15 is 8 h 30 min; minus a 30-minute break gives 8 h 0 min (8.00 decimal hours). If the end time is earlier than the start, the shift runs past midnight and 24 hours are added. To convert minutes to decimal hours, divide by 60: 45 min = 0.75 h.
Hours and minutes vs. decimal hours
Payroll and invoices use decimal hours, clocks use hours and minutes – and mixing them is the classic timesheet error. 7 h 30 min is 7.5 hours, not 7.30.
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 6 | 0.10 | 30 | 0.50 |
| 10 | 0.17 | 40 | 0.67 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
Night shifts
From 22:00 to 06:30 the end looks “earlier” than the start. The calculator notices this and counts across midnight: 8 h 30 min before breaks. For shifts longer than 24 hours, add the days separately.
Three ways to use it
- Time between – daily hours worked, with an unpaid break and optional pay at your hourly rate.
- Add / subtract time – when will a 7 h 45 min job started at 09:00 end? (16:45.) Crossing midnight shows “1 day later”.
- Add up durations – a week’s timesheet, video clip lengths or study sessions. Mix formats freely: 2:30, 1h 45m, 50m and 3.25.
Counting days rather than hours? The Date & Age Calculator finds the days between two dates and your exact age. Once your hours are added up, the salary calculator turns them into weekly, monthly and yearly pay.
How to calculate hours worked
- Pick the calculation. Time between two times, add/subtract time, or add up a list.
- Enter the times. Use the 24-hour format or your phone’s time picker; overnight shifts are handled.
- Subtract breaks. Enter unpaid break minutes to get paid hours.
- Use decimal hours. Copy the decimal figure into your timesheet or invoice.
Worked example: a week’s timesheet
| Day | Hours worked | Decimal |
|---|---|---|
| Monday | 8 h 30 min | 8.50 |
| Tuesday | 7 h 45 min | 7.75 |
| Wednesday | 9 h 15 min | 9.25 |
| Thursday | 8 h 00 min | 8.00 |
| Friday | 6 h 30 min | 6.50 |
| Total | 40 h 00 min | 40.00 |
Type the five durations into “Add up durations” in any format – 8:30, 7h 45m, 9.25 – and the calculator returns 40 h and 40.00 decimal hours, ready for payroll.
Common timesheet mistakes
- Writing 7 h 30 min as 7.30 instead of 7.50.
- Forgetting to deduct unpaid breaks.
- Losing hours on night shifts that cross midnight.
- Rounding every entry instead of only the weekly total.
Frequently asked questions
How do I calculate hours worked?
Subtract the start time from the end time and deduct unpaid breaks. 08:45 to 17:15 minus 30 minutes is 8 hours.
How do I convert minutes to decimal hours?
Divide the minutes by 60. 15 minutes is 0.25 hours, 45 minutes is 0.75 hours.
What if the shift goes past midnight?
Enter the times as they are, e.g. 22:00 and 06:30. The calculator adds 24 hours automatically.
Can I add up a whole week?
Yes. Choose “Add up durations” and enter each day on a new line.
Does it handle seconds?
In “Add up durations” you can write h:mm:ss, like 1:05:30. Results are shown to the minute.
How do I work out pay?
Enter your hourly rate in “Time between” and the calculator multiplies it by the decimal hours.
How many hours is 9 to 5?
8 hours. With a 30-minute unpaid lunch it is 7.5 paid hours.
How do I add hours and minutes together?
Add the minutes, convert every 60 minutes into an hour, then add the hours – or type each duration on its own line in “Add up durations”.