Precision Stopwatch
A drift-free stopwatch with lap timing.
Controls
About this tool
Measure drift-free elapsed time and compare lap splits using performance.now. Free, private and browser-based. Precision Stopwatch runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- Precision Stopwatch is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use Precision Stopwatch?
Open Precision Stopwatch, enter or paste your input, and copy the result. The page works without an account.
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