Refresh Rate Test

Measures how many times per second your screen is redrawn (Hz) and names the nearest standard refresh rate, such as 60, 120 or 144 Hz. Use it to check that a high refresh rate monitor is set up correctly.

How to use

1. Measuring starts by itself a moment after the page opens. Wait without touching the mouse or screen.
2. Read the "Measured refresh rate (median)" and the nearest standard refresh rate.
3. Change the "Duration" (3, 5 or 10 seconds) or move the window to another monitor, then press "Measure again".
4. Look for hitches in the "Frame time graph" and check the "Moving bar" for smooth motion. "Screen information" below shows the resolution and scale.

How it works

• The page times the gaps between the browser's drawing callbacks (requestAnimationFrame): refresh rate = 1000 ÷ frame time in ms. A frame that takes more than 1.5 times the usual frame time counts as a hitch.
• The result is how fast the browser draws, so browser settings, power saving, battery mode and variable refresh rate (VRR) can make it lower than the monitor's maximum.

Questions and answers

Why does my 144Hz monitor show 60Hz?

First check that the refresh rate in your operating system's display settings is not set to 60 Hz. Power saving or battery mode on a laptop can also lower it, and with several monitors this window must be on the one you are testing.

What is the difference between refresh rate (Hz) and FPS?

The refresh rate is how many times per second the monitor redraws the screen. FPS is how many images per second a game or program produces. On a 60 Hz monitor you see at most 60 images per second, even if the FPS is higher.

How is frame time calculated?

Frame time in ms is 1000 ÷ refresh rate. The screen changes about every 16.7 ms at 60 Hz, 8.3 ms at 120 Hz and 6.9 ms at 144 Hz.