Lookup
- Input
- performance.now()
- Expected output
- milissegundos desde timeOrigin
Use the result as technical reference and confirm official sources when there is operational impact.
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stopwatch performance api
Understand why performance.now() is better than the system clock for measuring duration.
Use the result as technical reference and confirm official sources when there is operational impact.
The main tool remains interactive; this page organizes the search intent.
The duration stays correct because it is always recomputed from the difference between two readings of the monotonic clock, not by adding up ticks. What may slow down is the on-screen drawing, since browsers throttle frame scheduling in hidden tabs. When you return to the tab, the displayed number jumps straight to the right value.
performance.now() is monotonic: it does not go backwards when the system clock is adjusted. That makes duration measurement more stable.
Yes. The main interface runs in the browser and avoids uploading sensitive data when the feature depends on local hardware.
Times, laps and sessions stay in this browser's local storage only and are never sent to a server.