# Time duration calculator

Canonical page: https://nepocore.com/tools/duration-calculator/

Add or subtract two durations written as hours, minutes and seconds. Display a signed result together with total seconds and decimal hours.

## How to use it

1. Enter the numbers, dates or units you want to compare.
2. Choose the calculation options and calculate.
3. Review the result together with the assumptions shown.

## Example

Add 01:35:20 and 00:45:50 to work out a combined session length.

## Limits and checks

These are durations rather than clock times. Hours can exceed 23, but minutes and seconds must be between 0 and 59.

## Access and processing

Free to use without an account. Interactive processing requires JavaScript in a modern browser. Input is processed in the browser rather than sent to a processing server. Optional browser storage is not a synchronized account.


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