Time Duration Calculator

Calculate the exact time difference between two times, or add/subtract time from a specific starting point.

Find Duration

Add/Subtract Time

Start Time

End Time

0 hours 0 minutes

Start Time

Operation

Hours

Minutes

12:00 AM

How it works

If End Time < Start Time (Overnight):
Duration = (24:00 - Start Time) + End Time
Else:
Duration = End Time - Start Time

Examples

9:00 AM to 5:00 PM: 8 hours, 0 minutes (480 total minutes)
10:30 PM to 6:15 AM (overnight): 7 hours, 45 minutes
Add 2 hours 15 mins to 1:45 PM: Result is 4:00 PM

Frequently Asked Questions

How does this handle overnight times?

If your end time is earlier in the day than your start time, the calculator automatically assumes the end time is on the following day and adds 24 hours to the calculation.

Can I calculate down to the second?

Standard HTML time inputs handle hours and minutes natively. Seconds are assumed to be 00 unless the browser supports second-level selection. The total seconds are derived from the minutes.

How do I subtract time?

Use the "Add/Subtract Time" tab, select "Subtract", and enter the hours and minutes you want to subtract from your base time.

What format are the results in?

The main result shows Hours and Minutes. We also provide total minutes and total seconds for your convenience.