Time Calculator
Add or subtract two durations in hours and minutes to get an accurate total.
What This Time Calculator Does
This tool adds or subtracts two durations given in hours and minutes, without you needing to manually carry over minutes into hours. It's useful for adding up work hours, calculating total time spent on tasks, or finding the difference between two durations.
How It Works
Each duration is first converted into total minutes, then added or subtracted, and finally converted back into a clear hours-and-minutes format. When subtracting, if the second duration is longer than the first, the result is shown as a negative duration.
Frequently Asked Questions
Can I enter minutes over 59?
Yes, the calculator will still add them up correctly, since everything is converted into total minutes before being converted back to hours and minutes.
What if the subtraction result is negative?
The result will show a minus sign, indicating that the second duration is longer than the first.
Can I use this for clock times instead of durations?
This tool is designed for durations (like "2 hours 30 minutes"), not specific clock times such as 3:00 PM. Use the Date Calculator for date-based calculations.
How to check this result
Enter hours and minutes in the same clock convention throughout the calculation.
Method and assumptions
The tool converts time into minutes, performs the addition or subtraction, then converts the result back into hours and minutes.
Before making a decision
For payroll or travel records, check whether unpaid breaks, time zones or daylight-saving changes need separate treatment.
Durations use base 60
Method and inputs
Enter whole hours and minutes between 0 and 59. Convert each duration to minutes using 60 × hours + minutes, add or subtract the totals, then convert back. These fields represent elapsed durations rather than clock times.
Worked example
Adding 1 hour 45 minutes and 2 hours 30 minutes gives 105 + 150 = 255 minutes, or 4 hours 15 minutes. Subtracting 3 hours from 2 hours 20 minutes gives −40 minutes.
Limits and common mistakes
Do not enter 1.5 in the hours field to mean one hour and a half: enter 1 hour and 30 minutes. Decimal payroll hours use a different notation; 1 hour 30 minutes equals 1.5 decimal hours.
Can a duration exceed 24 hours?
Yes. A duration can span multiple days. This calculator does not apply calendar dates, time zones or daylight-saving changes.
Content updated: 2026-10-03.