Time Calculator

Calculate the duration between two times, add hours and minutes to a start time, or subtract time from an end time. Results include hours, minutes, seconds, and decimal hours for timesheets and payroll. Handles overnight shifts automatically when the end time is earlier than the start time.

Free Tool Supports 12-hour and 24-hour formats. Overnight times handled.
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Duration Between Times
Add Time
Subtract Time

Start Time

End Time

8h 30m
duration
-
Hours : Minutes
-
Decimal Hours
-
Total Minutes
-
Total Seconds
Result: -

Minutes to Decimal Hours

MinutesDecimalMinutesDecimal
5 min0.0835 min0.58
10 min0.1740 min0.67
15 min0.2545 min0.75
20 min0.3350 min0.83
25 min0.4255 min0.92
30 min0.5060 min1.00

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This calculator uses 24-hour time internally. For payroll and invoicing, the decimal hours figure is typically the most useful output.

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Who this calculator is for

This calculator is for anyone adding or subtracting times and durations, for timesheets, scheduling or working out elapsed time.

What this calculator assumes

  • The times or durations you enter.
  • Standard 24-hour arithmetic.
  • It does not adjust for time zones or daylight saving unless stated.
  • Results are shown in hours and minutes.

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