Refresh rate test

Browsers draw animation frames in sync with the display. The test records the time between frames for a few seconds, removes outliers caused by dropped frames, and calculates the refresh rate from the average frame time. It snaps to the nearest common value (60, 75, 120, 144, 165, 240 Hz and so on) when the measurement is close, and also shows the measured average, the frame time, the jitter and the number of dropped frames.

Frame time = 1,000 ÷ refresh rate.

The motion tab moves the same object across the screen at three update rates: every frame (full frame rate), every second frame (half) and every fourth frame (quarter). On a 144 Hz monitor that means 144, 72 and 36 updates per second, so you can compare them directly and see what higher refresh rates actually buy you. Adjust the speed in pixels per second; faster motion makes the difference more obvious.

If the full-rate row looks no smoother than the half-rate row, your display is probably not running at the rate you expect. If one row stutters irregularly, frames are being dropped: close other apps and tabs.

Some monitors, especially when overclocked above their rated refresh rate, accept the signal but quietly skip frames. Your eyes can't see that, but a camera can. The test shows a pattern that changes position on every frame. Photograph the screen with a long exposure, for example by using your phone camera's manual or pro mode with a shutter speed around a tenth of a second or slower, so the photo captures several frames at once. Every frame should leave its mark evenly; gaps mean the monitor skipped frames. If you see them, lower the overclock step by step and photograph again until they disappear.

A moving bar travels across several gray backgrounds. Look for a blurry trail behind it (ghosting, pixels changing too slowly) or a bright or dark halo (overshoot, overdrive pushed too hard). Try each overdrive or response time setting in your monitor's on-screen menu and pick the one with the cleanest edges across all the grays. Every panel behaves differently, so there is no universal best setting.

The built-in troubleshooter under the test detects your system and walks you through the fixes. The most common ones:

• Windows 11: Settings › System › Display › Advanced display › Choose a refresh rate, and pick the highest value for that monitor.
• Mac: System Settings › Displays › Refresh rate (ProMotion displays adjust automatically).
• Cable and port: older HDMI versions can't carry high refresh rates at high resolutions. Use DisplayPort or a newer HDMI cable and port, and plug into the graphics card, not the motherboard.
• Power saving: laptops on battery and phones in Low Power Mode or battery saver often drop to 60 Hz. Plug in and test again.
• Variable refresh rate: with G-SYNC, FreeSync or adaptive displays, an idle browser page may run below the maximum.
• Browser: keep the tab in front and turn on hardware acceleration in your browser settings if it's off.

For office work, 60 Hz is perfectly usable. The jump to 120 or 144 Hz is the one most people notice: the pointer, scrolling and window dragging feel smoother, and fast games are easier to track. Beyond that the gains get smaller. Your graphics card also has to produce enough frames: a 240 Hz monitor showing a game at 70 FPS still looks like 70 FPS.

The test measures the rate this browser tab renders at. Multi-monitor setups show the rate of the screen the window is on. For a full check of a new display, also run the dead pixel test, and gamers may want to compare their reaction time before and after.