Add, subtract, and calculate time differences
Add, subtract, and convert time values without the headache of base-60 arithmetic. Enter durations in hours, minutes, and seconds, then add or subtract them to get a precise total. The converter handles unit changes between seconds, minutes, hours, and days.
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You are tallying billable time and need to add 2 h 45 m and 1 h 30 m, then know the decimal hours.
Input
2:45 + 1:30
Result
4:15 (= 4.25 hours)
Time arithmetic carries in base 60, so 45 + 30 minutes rolls into an extra hour rather than "75". The tool also converts the total to decimal hours, which is what timesheets and invoices usually require.
Add, subtract, and convert time values without the headache of base-60 arithmetic. Enter durations in hours, minutes, and seconds, then add or subtract them to get a precise total. The converter handles unit changes between seconds, minutes, hours, and days.
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Yes. The calculator handles any duration, there is no 24-hour cap.
Enter values as HH:MM:SS, or fill in the hours, minutes, and seconds fields separately.
The tool works with whole seconds. For sub-second precision, convert milliseconds to decimal seconds before entering.
Every calculation runs locally in your browser. Your numbers and expressions are not transmitted or stored.