Refresh Rate Test
Browsers expose an animation frame counter; over five seconds it settles near your display's true driving rate. If a monitor sold as 144 Hz measures 60, you are on the wrong cable, the wrong port, or the wrong OS setting.
Click Start and wait 5 seconds — the measured value is your real driving rate.
How to use this test
Click Start — the test opens fullscreen over this page (nothing is installed, nothing leaves your browser). A control bar at the bottom of the screen lets you switch colors and exit with one tap — touch screens included; the Esc key and your browser's back button work too. Judge the screen in the lighting the test asks for; judging bleed or uniformity in a bright room defeats the test.
Frequently asked questions
Why does my 144 Hz monitor measure 60?
Almost always a cable or port limit (HDMI vs DisplayPort), or Windows is still set to 60 Hz in display settings.
Is the measurement exact?
It is the browser compositor rate — accurate enough to catch a 144 Hz panel running at 60, which is what it is for.