Refresh Rate Test
Measure your display's refresh rate in Hz and see how smooth its motion is. Useful for confirming your 60, 120, 144 or 240 Hz monitor is actually running at full speed.
If the green box stutters, your browser or monitor may not be running at full refresh rate.
How the refresh rate test works
Your browser tries to draw a new frame every time your monitor refreshes. This test counts those frames over a few seconds and reports the average as your refresh rate in hertz (Hz). A 60 Hz screen draws 60 frames per second; a 144 Hz gaming monitor draws 144.
Getting an accurate reading
- Close other heavy tabs and apps so the browser isn't slowed down.
- Run the test for at least 5 seconds for a stable average.
- If the number is below your monitor's rating, set the correct Hz in your OS display settings (Windows: Display → Advanced display; macOS: Displays).
Frequently asked questions
How do I check my monitor refresh rate?
Start the test, wait a few seconds, and read the Hz value — typically 60, 120, 144 or 240.
Why is it slightly off, like 143 instead of 144?
Browser timing has tiny variations, so a reading within a frame or two of the rated value is normal and means your monitor is running correctly.