How to use the Monitor Refresh Rate Test
Keep the tab visible, start the measurement, and avoid moving the window while the browser collects animation frames. Run several attempts after selecting the intended operating-system display mode. Record the rounded result and frame time together instead of relying on one instant reading.
How to interpret your result
The estimate converts average animation-frame spacing into hertz; 60Hz is about 16.67 ms per frame and 144Hz about 6.94 ms. A stable result near the configured mode supports that browser path, while occasional drops indicate scheduling or load. It is more useful for comparison than for claiming exact panel performance.
Important limitations
requestAnimationFrame timing is not an oscilloscope measurement and cannot see pixel response, scan-out, VRR transitions, or cable quality directly. Background tabs, battery saving, remote desktop, and browser throttling can lower the estimate. The browser may report a compositor cadence different from the panel hardware.
Troubleshooting checklist
Confirm the operating-system refresh mode and connect the display directly where possible. Close heavy tabs, disable battery-saving limits, and repeat with the browser window focused. If only one browser differs, update it and test without extensions before investigating the cable or adapter.
Practical use cases
Use this check after buying a high-refresh monitor, changing a cable, or enabling a new display mode. Developers can compare compositor behavior across browsers. Gamers should pair it with an input-latency and motion test because refresh rate alone does not prove low end-to-end latency.
Try the live tool
Open Monitor Refresh Rate Test
Frequently asked questions
Is this a precise monitor measurement?
No. It estimates the browser animation cadence; use a hardware tool for panel response and exact scan-out measurements.
Why does it show 60Hz on a 144Hz monitor?
Check the selected OS mode, battery settings, browser focus, cable or adapter, and whether a remote desktop session is active.