What is the Time Addition Calculator?
Add or subtract hours, minutes and seconds.
Enter hours, minutes, seconds and operation and the Time Addition Calculator returns result, in seconds, in minutes and in hours. Results update as you type, and nothing you enter leaves your device.
How it is calculated
Convert both times to seconds, add or subtract, then convert back
How to use it
- Enter hours.
- Enter minutes.
- Enter seconds.
- Choose operation.
- Enter hours.
- Enter minutes.
- Enter seconds.
- Read result in the results panel. It updates as you type.
- Change any value to compare scenarios, or use Share to send the result as a link.
Worked example
Common questions
What formula does the Time Addition Calculator use?
It uses: Convert both times to seconds, add or subtract, then convert back.
What do I need to use the Time Addition Calculator?
You need hours, minutes, seconds and operation. Sensible starting values are filled in so you can see how it works straight away.
Is the Time Addition Calculator free, and is my data stored?
It is free with no sign-up. The calculation runs in your browser, so the values you enter are not sent to or stored on our server.