DataToolsLab
Date & Time Tools

Time Duration Calculator

Calculate the duration between two times or add up multiple durations.

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What is Duration?

A duration calculator with two modes: the span between a start and end clock time, or the total of several time-length entries.

How it works

Times are converted to minutes past midnight; overnight spans add 24 hours when the end is earlier than the start. Durations sum in normalized units.

  1. Enter your input. Type or paste your input into the field above — the tool responds instantly.
  2. Review the result. Output updates live as you type. Everything runs entirely in your browser.
  3. Copy or download. Use the Copy button to grab the result, or Download to save it as a file.

Examples

Realistic sample

Paste or type any realistic input — the tool computes the result locally and instantly.

Common mistakes

Expecting a server round-trip

Nothing is uploaded — every tool in this category runs entirely in your browser.

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