How to calculate hours worked
For each shift, subtract the start time from the finish time and deduct the unpaid break. If the finish is earlier than the start, it is treated as the following day; if they match, enter a shift shorter than 24 hours. Add all exact minutes before converting the total into hours and minutes or decimal hours. You can also add and subtract durations such as 2:30 and 0:45. Calculations use nominal clock time and do not adjust for daylight-saving time changes, labour laws or premium rates.
Example: 08:30 to 17:00 is 8 h 30 min; subtract a 30-minute break to get 8 h worked. Five identical shifts make 40 h.
Results are estimates and depend on the supplied values.
Guide to calculating hours and minutes
How to calculate a working shift
Subtract the start time from the finish time, then deduct unpaid break minutes. A finish earlier than the start means the shift continues into the next day.
Start 08:30 · finish 17:00 · 30-minute break → 8 h net.
How to total hours across several days
Add exact minutes from each shift before converting to decimal hours. This avoids accumulated rounding errors.
7:45 + 8:15 + 6:30 = 22 h 30 min = 22.50 h.
How to convert hours and minutes to decimal hours
Divide the minutes by 60, then add the whole hours. Thirty minutes is 0.5 hours, not 0.30.
7 h 30 min = 7 + 30/60 = 7.5 decimal hours.
How to count an overnight shift
A shift from 22:00 to 06:00 ends the next day. Calculate 8 gross hours, then deduct your break.
22:00 → 06:00 next day = 8 h; with a 45-minute break = 7 h 15 min.
When to use “Add and subtract hours”
If you already have durations such as 2:30, 1:15 or −0:45, use the second mode. No clock-in or clock-out time is needed.
2:30 + 1:15 − 0:45 = 3:00.
Important for timesheets and payrollThis tool uses nominal clock minutes. It does not account for daylight-saving transitions, public holidays, night-work premiums, labour agreements, employer rounding rules or breaks that count as paid work. Comparing against expected hours is informational only and does not classify legal overtime. Double-check actual elapsed time when a shift crosses a clock or time-zone change.
Frequently asked questions
How do I calculate hours worked in a week?
Add a shift for each day with start time, finish time and break. The calculator totals exact net minutes.
How do I deduct a lunch break?
Enter the break in minutes. For a 09:00 to 18:00 shift with a 60-minute break, the total is 8 h.
Does it handle overnight shifts?
Yes. A finish time earlier than the start is treated as the following day. A 22:00 to 06:00 shift is 8 gross hours.
Are 7:30 and 7.30 hours the same?
No. 7:30 means 7 h 30 min, equivalent to 7.5 decimal hours. In decimal, 7.30 h is 7 h 18 min.
Does this determine overtime under my contract?
No. It only compares your result to optional expected hours. It does not apply employment regulations or determine overtime rights.
Does the calculator save my times?
No. Calculations happen in your browser. This module does not store or send your entered shift times to CalcMetria.