Refresh Rate Test – Check Your Monitor’s Hz Online
Find out at how many hertz your screen is really running. The test measures the time between frames in your browser and shows the refresh rate, frame time and dropped frames.
Just open the page: after about a second it shows your refresh rate, for example “≈ 144 Hz”, measured from the time between frames. If a 144 Hz monitor shows 60 Hz, the refresh rate is set wrong in your display settings or the cable cannot carry the higher rate.
How to use Refresh Rate Test
- Open the page and keep the tab in the foreground.
- Wait a second while frames are measured.
- Read the refresh rate and frame time.
- Watch the moving ball for smoothness.
- Move the window to another monitor to test it.
How the test works
Browsers draw a new frame once per screen refresh. By measuring the time between frames with requestAnimationFrame, the tool calculates the refresh rate: 16.7 ms per frame is 60 Hz, 8.3 ms is 120 Hz and 6.9 ms is 144 Hz. The value is snapped to the nearest standard rate when it is within 3 %.
| Refresh rate | Frame time | Typical device |
|---|---|---|
| 60 Hz | 16.7 ms | Office monitors, older phones |
| 90 Hz | 11.1 ms | Mid-range phones |
| 120 Hz | 8.3 ms | Modern phones, MacBook Pro, TVs |
| 144 Hz | 6.9 ms | Gaming monitors |
| 240 Hz | 4.2 ms | Esports monitors |
My monitor shows the wrong value
A 144 Hz monitor often runs at 60 Hz out of the box. Check these points:
- Windows: Settings → System → Display → Advanced display → choose refresh rate.
- macOS: System Settings → Displays → Refresh rate.
- Use DisplayPort or a recent HDMI cable; old HDMI cables limit high refresh rates.
- Make sure the graphics driver is up to date.
Why the number can be lower
Battery saving modes, variable refresh rate (FreeSync, G-Sync, ProMotion) and background tabs can lower the measured value. Phones with adaptive refresh drop to 60 Hz or less when nothing moves on screen; the moving ball keeps the screen busy so it reports the maximum rate. If many frames are slow, close other programs and browser tabs.
Refresh rate vs frame rate
The refresh rate is how often the screen can show a new image; the frame rate (FPS) is how many images your computer or game delivers. A 60 FPS game on a 144 Hz monitor still looks smoother than on 60 Hz, but you get the full benefit only when both match.
See your resolution on Screen Resolution and check pixels with the Dead Pixel Test.
You may also find these free tools useful: Keyboard Tester, Gamepad Tester and Screen Resolution.
Frequently asked questions
How do I check my refresh rate?
Open this page and wait a second. It measures frame times and shows the rate, such as 60, 120 or 144 Hz.
Why does my 144 Hz monitor show 60 Hz?
The rate is probably set to 60 Hz in the display settings, or the cable does not support 144 Hz.
Is the result accurate?
Within a few percent. Background tabs, battery saving and variable refresh can lower it.
What is a good refresh rate?
60 Hz is fine for office work; 120–144 Hz feels much smoother for scrolling and gaming.
Does it work on phones?
Yes. Phones with 90 or 120 Hz screens show their rate while the ball is moving.
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