Duration calculator
This calculator adds up lengths of time, such as video clips, workout splits or hours worked. It can also subtract later durations from the first one. Results are shown as hours:minutes:seconds plus totals in seconds and decimal hours.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
01:30:00 00:45:30
Duration: 02:15:30 Seconds: 8130 Hours: 2.25833333333
How to use the duration calculator
- Type one duration per line as hours:minutes:seconds, such as 01:30:00.
- Choose an Operation: Add all durations, or Subtract later durations from the first.
- Press Run to get the total.
- Use Copy result or Download.
How it works
Enter 2 to 100 nonempty lines.
Hours can have 1 to 6 digits and can go past 24. Minutes and seconds need two digits from 00 to 59.
Up to three fractional second digits are allowed, such as 00:00:05.250.
Subtracting can produce a negative result, shown with a minus sign.
Formats like 1h 30m or 90:00 with only two parts are rejected.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
How do I add hours and minutes together?
Write each time as hours:minutes:seconds on its own line, for example 01:30:00 and 00:45:30, keep Add all durations selected and press Run. That example totals 02:15:30.
How do I convert a duration to decimal hours?
Every result includes an Hours line. For example, 01:30:00 is 1.5 hours.
Can the total go over 24 hours?
Yes. The total keeps counting hours, so it does not roll over into days.
Can I enter minutes only, like 45?
No. Each line needs all three parts, so 45 minutes is written 00:45:00.