How the time card calculator works
For each day the calculator takes end time − start time − unpaid break. If the end time is earlier than the start time, it assumes the shift ran past midnight and adds 24 hours. Daily totals are added up for the week and shown both in hours:minutes (for example 37:45) and in decimal hours (37.75), which is what payroll and invoices use.
Converting minutes to decimal hours
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 6 | 0.10 | 30 | 0.50 |
| 12 | 0.20 | 36 | 0.60 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
Divide minutes by 60. So 7 hours 45 minutes is 7 + 45/60 = 7.75 hours.
Overtime rules (US)
Under the federal Fair Labor Standards Act, non-exempt employees must be paid at least 1.5 times their regular rate for hours over 40 in a workweek. Some states go further – California, for example, also requires daily overtime after 8 hours. Change the threshold and multiplier above to match your rules. This calculator applies weekly overtime only.
Worked example
Monday to Friday, 9:00 to 17:30 with a 30-minute unpaid lunch, is 8 hours a day and 40 hours a week. At $25 an hour that is $1,000. Add a Saturday shift from 9:00 to 13:00 and the extra 4 hours are overtime at $37.50, adding $150 for a total of $1,150.
Freelancers: turn hours into an invoice
If you bill clients by the hour, use the weekly total as the quantity on your invoice, or track hours per client with the billable hours calculator.
Frequently asked questions
How do I calculate hours worked?
Subtract the start time from the end time, then subtract unpaid breaks. For 8:45 to 17:15 with a 30-minute break: 8 h 30 min − 30 min = 8 hours.
How do I handle overnight shifts?
Just enter the real times, for example 22:00 to 06:00. When the end time is earlier than the start, the calculator treats the shift as crossing midnight.
Are breaks paid?
Under US federal law, short breaks (usually 5–20 minutes) are paid, while meal breaks of 30 minutes or more where the employee is fully relieved are usually unpaid. Enter only unpaid break minutes.
What is time and a half?
Overtime paid at 1.5 times the regular hourly rate. At $20 an hour, overtime is $30 an hour.
