Hours Calculator
Work out the hours between a start time and an end time, subtract an unpaid break, and see the total in both h:mm and decimal hours — the two formats timesheets ask for.
Formula and calculation
Worked example
From 09:00 to 17:30 with a 30-minute break: 8 h 30 min of elapsed time minus 30 min is 8 h, which is 8 in decimal hours.
Decimal hours vs. h:mm
Payroll software usually wants decimal hours: 7 h 45 min becomes 7.75, because 45 minutes is three-quarters of an hour. The conversion trip-ups are 6-minute blocks — 7 h 06 min is 7.10, not 7.06. Enter the times here and read both formats, or use the h:mm result to check a timesheet entry. Breaks are the other classic error: a 40-minute lunch should be deducted before converting, not after.
What the results mean
- Hours worked
- Total time between the two clock times, minus the break — shown as hours and minutes.
- Decimal hours
- The same total in decimal hours (8 h 30 min = 8.50). Payroll systems usually want this form.
- Regular (first 8 h)
- Time up to 8 hours in the day, the most common full-time threshold.
- Overtime (beyond 8 h)
- Time beyond 8 hours. Whether and how it is paid depends on your jurisdiction and contract — some places use a weekly threshold instead of a daily one.
Frequently asked questions
How do I calculate the hours I worked from a timesheet?
Subtract the start time from the end time, write the result as hours and minutes, then subtract unpaid breaks. 09:00 to 17:30 is 8 h 30 min; minus a 30-minute break leaves 8 hours exactly. This calculator shows that arithmetic in both h:mm and decimal hours.
How do I convert hours and minutes to decimal hours?
Divide the minutes by 60 and keep the hours. 8 h 45 min is 8 + 45/60 = 8.75 decimal hours. Common fractions: 15 min = .25, 30 min = .50, 45 min = .75 — worth memorising if you fill timesheets.
What counts as overtime?
In the US, the federal standard is time over 40 hours in a workweek, though some states use daily thresholds — California, for example, requires overtime after 8 hours in a day. This calculator splits out time past 8 hours per day as a convenience; check the rule that applies to you.
How do overnight shifts work?
Enter both times normally — 22:00 to 06:00. When the end time is earlier than the start time, the calculator adds 24 hours, treating it as one continuous shift across midnight.