← The checklist

Step 3 of 5 / 30 sec

Browser refresh rate

A short frame-timing sample. Stay on this tab and keep the window visible while it runs.

requestAnimationFrame · 8-second sample
Estimated browser frame rate

—Hz

Ready when you are.
Median frame time— ms
Timing stability within ±10% of median—
Nearest common rate reference only— Hz

The chart will show actual frame intervals, not a simulated signal.

How to check

  1. Connect the monitor you want to check and move this browser window onto it.
  2. Close heavy background work, select your intended refresh rate in system settings and press Start measurement.
  3. Wait for the sample to finish. Repeat after changing display settings if needed.

Know the limits

This estimates browser animation callback cadence, not physical panel scanout. A compositor can repeat or drop frames after the callback, and variable-refresh displays may change their rate.

Background tabs, power-saving modes, thermal limits, other workloads and browser timing precision affect the result. A hidden tab invalidates the sample.

The nearest common rate is a numerical reference. It does not identify your monitor or prove that a setting is enabled.

A useful question

Why does a 144 Hz monitor show a lower number?

The browser may be capped, the system may be set to a different rate, or the current workload may limit callbacks. Check the operating system’s display settings and repeat with the tab visible.

Finished inspecting? Your observations stay with you.Done — continue to step 4

Browser visual tests are diagnostic aids, not replacements for professional hardware measurement.