DataToolsLab
Date & Time Tools

Stopwatch & Timer

A precise browser stopwatch and countdown timer with lap support.

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What is Stopwatch?

A pair of timing tools: a start/stop/reset stopwatch with lap recording, and a countdown timer for a set number of minutes and seconds.

How it works

Elapsed time is computed from performance.now() deltas rather than accumulated ticks, so it stays accurate even if the tab is throttled.

  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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