How the work hours calculator works
Enter three things:
- Start time and end time, in 24-hour format.
- Unpaid break in whole minutes (leave 0 if your breaks are paid).
- Optionally, Overtime after (hours per day), for example 8.
The calculator subtracts the start time from the end time, removes the break and shows the time worked as hours and minutes, in words and in decimal hours. When you set an overtime threshold, it also splits the result into regular time and overtime.
If the end time is earlier than the start time, the shift is assumed to cross midnight and a notice says so. A shift that starts and ends at the same time, or a break as long as the shift, is flagged as an error rather than guessed.
Examples
| Shift | Break | Time worked | Decimal hours |
|---|---|---|---|
| 09:00 – 17:30 | 30 min | 8:00 | 8.00 |
| 22:00 – 06:30 | 45 min | 7:45 | 7.75 |
| 07:00 – 18:00 | 30 min | 10:30 | 10.50 |
| 08:15 – 12:35 | none | 4:20 | 4.33 |
With Overtime after 8 hours, the 07:00 – 18:00 shift shows 8:00 regular time and 2:30 overtime: 11 hours on site, minus 30 minutes of break, is 10 hours 30 minutes, of which 2 hours 30 minutes are beyond the threshold.
The night shift works the same way: 22:00 to midnight is 2 hours, midnight to 06:30 is 6 hours 30 minutes, so 8 hours 30 minutes in total, minus 45 minutes of break, gives 7 hours 45 minutes.
Why decimal hours matter
Payroll systems and many timesheets use decimal hours, where 30 minutes is 0.5 and 15 minutes is 0.25. Writing 7:45 as 7.45 is a common mistake that undercounts the shift by 18 minutes: 7.45 hours is 7 hours and 27 minutes. This payroll hours calculator always shows both forms side by side.
Common uses
- Checking a single day’s hours before filling in a timesheet.
- Working out a night or weekend shift that crosses midnight.
- Using it as a time clock calculator: turning a clock-in and clock-out time into decimal hours for an invoice.
- Seeing how much of a long day counts as overtime under a daily threshold.
Good to know
- The calculator uses exact minutes. Some employers round clock times, for example to the nearest quarter hour; check your workplace rules.
- It handles one shift at a time. For a full week with daily totals, weekly overtime and gross pay, fill in a weekly time card.
- To add up several durations, add and subtract hours and minutes with the time calculator.
- Your times stay on your device. The share link stores them after the # in the address, which browsers never send to servers.