Refresh rate test
The test starts on its own. Within a few seconds the big number shows your refresh rate in Hz, with the frame rate (FPS) stats underneath.
Refresh rate test workspace
How to use
4 short steps.
Keep this tab visible
Put the window on the monitor you want to check and leave it in front. The number settles after a few seconds.
Read the big number
It is your refresh rate in Hz. The line under it names the closest standard rate, such as 60, 120, or 144 Hz.
Compare it with your display settings
Open your system display settings and check the refresh rate set there. The two should match.
Watch the frame time chart
A flat line means steady frames. Spikes mean the browser missed frames, usually because the computer is busy.
What the result means
Match what you see to one of these.
If the number matches your monitor's rate, it is working
If you see 143.9 Hz on a 144 Hz monitor, the monitor, cable, and system are all running at that rate. Small decimals are normal.
If it reads 60 Hz on a faster monitor, something is capping it
If a 120 or 144 Hz monitor shows 60 Hz, the refresh rate in your system settings is still 60, the cable cannot carry the higher rate, or a power saving or browser setting is limiting it.
If the number keeps changing, frames are being dropped
If the reading wanders and the chart is spiky, the browser is not keeping up. Close other tabs and apps, plug in the power, and let it settle again.
Troubleshooting
If the test fails, try these in order.
Set the refresh rate in your system settings
On Windows, open Settings, System, Display, Advanced display and choose the rate. On macOS, hold Option while clicking Scaled in Displays. Then watch the number here again.
Move the window fully onto one monitor
A window that spans two screens can run at the slower one's rate. Drag it fully onto the monitor under test and let the number settle.
Use a cable rated for the rate
High rates at high resolutions need DisplayPort or HDMI 2.1. Swap the cable or port and check the number again.
Plug in and turn off power saving
Laptops often drop to 60 Hz on battery. Connect the charger, turn off battery saver, and check again.
Try another browser
Some browsers cap animation at 60 Hz on some systems. Open this page in Chrome, Edge, or Firefox and compare.
What this test can't tell you
Where a browser check stops.
- The number comes from requestAnimationFrame timing, which follows the display refresh in most browsers but can be capped by the browser, a power setting, or variable refresh rate.
- It is the rate this page is drawn at, not the frame rate of a game; a game's FPS depends on the graphics card and can be higher or lower.
FAQ
Common questions about this test.
How do I test if my screen is 120Hz or 144Hz?
Leave this page open on that screen for a few seconds. If the big number reads about 120 or 144, the higher rate is active. If it reads 60, change the refresh rate in your system display settings and check again.
Is 60Hz basically 60 FPS?
In a browser, yes. The page can only be drawn once per refresh, so at 60 Hz the browser produces 60 frames per second. In a game, FPS is set by the graphics card and can be above or below the monitor's Hz.
Is 60Hz or 120Hz better?
120 Hz is smoother and feels more responsive, and it makes moving objects clearer. 60 Hz is fine for office work and video, which is mostly 24 to 60 frames per second anyway.
How can I check my FPS?
The cards on this page show the current, average, minimum, maximum, and 1% low frame rate of the browser. For a game's FPS, use the game's own counter or an overlay such as Steam's or your graphics driver's.
Why does the result differ from my monitor's advertised Hz?
The system setting is usually the reason: many monitors ship at 60 Hz and the higher rate must be selected. Cables, power saving, browser caps, and variable refresh rate can also lower the reading.