Refresh Rate Test
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Accuracy

Refresh Rate Test Accuracy Tips

How to get a refresh rate reading you can trust: give the browser nothing else to do, test the right screen, use full screen, check OS display settings, and read stability alongside Hz.

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The core idea

The test reports what the browser presents

A browser refresh rate test times the frames the browser actually delivers to the screen. The median frame time is very robust, so the Hz figure is usually right even on a busy machine. The stability, jitter and dropped-frame readouts are more sensitive, though, and they are where a noisy system shows up. Each tip below removes one source of noise.

  • 01

    Give the browser nothing else to do

    The test can only report frames the browser actually paints on time. A video in another tab, a game launcher updating, or an RGB utility polling the GPU can all push a frame past its deadline. Close what you can, then test.

  • 02

    Test the right screen

    With two or more monitors, the browser syncs to the screen the window is on. Mixed setups (for example a 144Hz main and a 60Hz side screen) can give odd results if the window spans both. Drag the window fully onto the monitor you want to check.

  • 03

    Use full screen on desktop

    Press F to make the test fill the display. Some desktop compositors handle full-screen windows with less overhead, and nothing else on the screen is redrawing while the test samples.

  • 04

    Check the OS setting before blaming the monitor

    If the result is lower than the rate on the box, check the operating system setting first. A monitor sold as 165Hz that tests at 60Hz is almost always set to 60Hz in display settings, not faulty.

  • 05

    Read stability, not just Hz

    A correct Hz with Fair or Unstable stability means the display is fine but frames are arriving unevenly, from background load, thermal throttling or a browser extension. Fix that, and games and scrolling will feel smoother too.

  • 06

    Use the motion test to see the difference

    Switch between 1×, 2× and 4× and watch the saucer’s edges against the tick marks. At high refresh rates, the edges stay crisp. At 60Hz, they smear, and dropped frames show up as visible jumps. It is the same idea as the classic UFO motion test, and it is useful for comparing two screens side by side.

Wrong number?

The four usual suspects

If the result is lower than your display is rated for, it is almost always one of these. The FAQ has step-by-step settings for Windows and macOS.

  • OS still set to 60Hz

    A new high-refresh monitor often ships running at 60Hz. On Windows, go to Settings → System → Display → Advanced display → Choose a refresh rate. On macOS, go to System Settings → Displays → Refresh Rate. Then run the test again.

  • Cable or port limits

    An older HDMI cable or port can cap a 1440p or 4K signal at 60Hz. Use DisplayPort or a certified HDMI 2.0/2.1 cable, and make sure it is plugged into the graphics card rather than the motherboard.

  • Power saving and battery

    Laptops and phones with adaptive or ProMotion screens drop to 60Hz, or lower, on battery or in low-power mode. Plug in, switch off Low Power Mode, and on Android check Settings → Display → Smooth display / Refresh rate.

  • Browser capping frames

    Some browsers limit animation frames when the window is not focused, when battery saver is on, or when hardware acceleration is off. Try another browser or enable acceleration. An unexpected 30Hz result is almost always a power-saving cap.

Want the details of the method? Read how the test works, or run it now.

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