Time Calculator
Add, subtract, and calculate differences between time values.
How the Time Calculator Works
The Time Calculator lets you add multiple time values together or find the difference between two times. Enter hours, minutes, and seconds for each time value, and the calculator handles all the carry-over arithmetic automatically.
Results are displayed in both standard HH:MM:SS format and decimal hours format. Decimal hours are useful for timesheets and billing — for example, 1 hour and 30 minutes equals 1.50 decimal hours. For work hour tracking with overtime, see our hours calculator or the full time card calculator.
Frequently Asked Questions
How do I add multiple time values?
Use the Add Time tab to enter multiple time values. Click the + Add Row button to add more rows. The calculator automatically sums all hours, minutes, and seconds, carrying over as needed (e.g., 75 minutes becomes 1 hour 15 minutes).
What are decimal hours?
Decimal hours express time as a decimal number. For example, 1 hour 30 minutes = 1.50 hours, and 2 hours 15 minutes = 2.25 hours. This format is commonly used in timesheets and billing.
Can I calculate the difference between two times?
Yes. Switch to the Time Difference tab, enter a start time and end time, and the calculator will show the difference in both HH:MM:SS and decimal hours format.
Is there a limit to how many time rows I can add?
No. You can add as many time rows as needed by clicking the + Add Row button. You need at least two rows, but there is no upper limit.