Time Duration Calculator – How It Works

This time calculator makes it easy to add or subtract values in the sexagesimal system. Quickly calculate a duration in hours, minutes, and seconds, taking into account the 60 minutes per hour and 60 seconds per minute.

How to Use It

Simply use your mouse and keyboard to enter the required values. For subtraction, make sure to put the larger time first. If the first row is smaller than the second, the tool automatically adjusts to prevent negative results.

Want a fresh start ? Just click Clear to reset everything.

Smart Carry Feature

By clicking Carry, the calculator saves the result and transfers it to the first row for your next calculation.

Auto Carry

With Auto Carry enabled, results are instantly saved and inserted into the first row – no extra clicks needed.

Time-Saving Keyboard Shortcuts

Boost your productivity with handy shortcuts. Calculate time faster without reaching for your mouse.

Here are the available shortcuts for adding or subtracting durations:

+ ⇝ Add

- ⇝ Subtract

m ⇝ Reset

w ⇝ Carry

Results History

Every operation is saved in a neat results table. Export your data in CSV for spreadsheets or in PDF for printing and sharing.

Practical Example

Quickly Calculate Work Hours

Need to calculate your work time from 8:43 to 13:09 ? This tool does it instantly (just use the Subtract button).

Result: 4 h 26.

Add Multiple Rows

Want to add up several durations at once ? Just add rows and calculate everything in one go. ⚠️ Note: This feature works for additions only. For subtractions, the tool keeps only the first two rows.