How to calculate hours worked
Adding up hours by hand is easy to get wrong, especially with breaks, overnight shifts and decimals. Here's the method payroll uses, step by step.
Step by step
- Write start and end times in 24-hour format: 9:15 am is 09:15 and 5:45 pm is 17:45.
- Subtract the start from the end: 17:45 − 09:15 = 8 hours 30 minutes.
- Subtract unpaid breaks: 8:30 − 0:30 lunch = 8 hours.
- Repeat for each day and add them up for the week.
Minutes to decimal hours
Divide minutes by 60: 7 hours 45 minutes is 7.75 hours. Multiply decimal hours by the hourly rate to get pay — 7.75 × $20 = $155.
| Minutes | Decimal hours |
|---|---|
| 15 | 0.25 |
| 20 | 0.33 |
| 30 | 0.50 |
| 40 | 0.67 |
| 45 | 0.75 |
Overnight shifts and overtime
If a shift ends after midnight, add 24 hours to the end time before subtracting: 22:00 to 06:30 becomes 30:30 − 22:00 = 8 hours 30 minutes.
Overtime depends on local law and your contract. In the US, federal law generally requires overtime for hours over 40 in a workweek, and some places also count hours over 8 in a day — typically paid at 1.5 times the normal rate.
Tools used in this guide
Related guides
How to calculate hours worked — FAQ
Work out each day's hours (end − start − breaks) and add them together. The time card calculator does this automatically.