Screen refresh rate test (Hz)

When to measure the refresh rate

The refresh rate (Hz) is how many times per second the screen redraws. If a device is sold as 90, 120 or 144 Hz, measure it when you buy it, and always after a screen replacement: many cheap replacement screens only run at 60 Hz even though they look identical to the original.

Why the result can be lower than the spec

• Battery saver is on: most devices lock the screen to 60 Hz to save power.
• The display setting is 60 Hz: on Android this is usually under Settings › Display › Motion smoothness (the name varies by brand).
• iPhone: every browser on iPhone limits web pages to 60 Hz, even on Pro models with ProMotion. For a real reading, turn on the Safari option described in the test.
• A laptop driving an external monitor or using an old cable: the port and cable cap the rate.
• A replacement screen that doesn't support high refresh rates.

What to do if it's too low

• Turn off battery saver, pick the highest rate in the display settings, and measure again.
• Still below spec after a screen replacement: tell the shop, because it's the wrong kind of screen. See checking a device after a repair.
• Also run the touch test: replacement screens often come with touch problems too.