Time Duration Calculator
Hours between two times, minus breaks — or add and subtract time.
Time worked
8h 0m
8.00 decimal hours
Total span
8h 30m
Break deducted
30 min
In minutes
480
Calculate the number of hours and minutes between two times of day, with an option to subtract an unpaid break — the calculation freelancers, hourly workers, and anyone doing timesheets need constantly. It also supports adding or subtracting a duration from a starting time.
Times that cross midnight are handled correctly, so an overnight shift from 10 PM to 6 AM still comes out to 8 hours rather than a negative number.
Decimal hours for invoicing
Timesheets and invoices are usually billed in decimal hours, not hours and minutes — and converting in your head is where rounding errors creep into invoices. 7 hours 45 minutes is 7.75 hours, not 7.45.
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 5 | 0.08 | 35 | 0.58 |
| 10 | 0.17 | 40 | 0.67 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
| 30 | 0.50 | 55 | 0.92 |
Divide minutes by 60 to convert. Most billing systems accept two decimal places; some round to the nearest quarter hour.
Getting overnight shifts right
When the end time is earlier than the start time, this calculator assumes the shift rolls into the next day rather than returning a negative number. A 22:00 to 06:00 shift is therefore 8 hours.
Two things it deliberately does not do: it doesn't apply overtime multipliers, and it doesn't adjust for daylight saving transitions. A night shift spanning a clock change is genuinely one hour longer or shorter in real time than the clock suggests, and payroll rules for that vary by employer and jurisdiction.
Frequently asked questions
- How does it handle a shift that crosses midnight?
- If the end time is earlier than the start time, the calculator assumes the end falls on the next day, giving the correct positive duration for overnight shifts.
- Can I subtract a lunch break from the total?
- Yes — enter the break length and it's deducted from the raw duration to give the actual worked time.
- Does this output decimal hours for payroll?
- Yes, the result includes both hours-and-minutes and decimal-hour formats, useful for timesheets billed in fractional hours.
- How do I convert minutes to decimal hours by hand?
- Divide by 60. 45 minutes is 45 ÷ 60 = 0.75 hours. The common mistake is writing 7 hours 45 minutes as 7.45 instead of 7.75.
- Does it account for daylight saving changes?
- No — it calculates clock-time differences. On the two nights a year when the clocks change, a shift's real elapsed time differs from the clock difference by an hour.