Lookup
- Input
- performance.now()
- Expected output
- milissegundos desde timeOrigin
Use the result as technical reference and confirm official sources when there is operational impact.
stopwatch performance api
Stopwatch with the Performance API
Understand why performance.now() is better than the system clock for measuring duration.
How to interpret it
- performance.now() is monotonic: it does not go backwards when the system clock is adjusted. That makes duration measurement more stable.
Quick example
Check
- Input
- cronômetro performance api
- Expected output
- stopwatch performance api
The main tool remains interactive; this page organizes the search intent.
Full tool FAQ
The duration remains correct because it is computed from a monotonic clock. Visual updates may slow down in background tabs because browsers save resources.
Frequently asked questions
Is Date.now() wrong for a stopwatch?
performance.now() is monotonic: it does not go backwards when the system clock is adjusted. That makes duration measurement more stable.
Does the tool work locally?
Yes. The main interface runs in the browser and avoids uploading sensitive data when the feature depends on local hardware.