Monitor Hz checker
Refresh Rate Test - Check Your Monitor Hz
Measure your display refresh rate in the browser. The test samples frame timing to estimate whether your screen is running at 60Hz, 120Hz, 144Hz, 165Hz, 240Hz, or higher.
Live measurement
Display refresh rate
Estimated refresh rate
Frame interval: -- ms
Closest standard rate
Timing jitter
Confidence
Keep this tab active during the test. Browser throttling, battery saver, mirroring, or a capped display mode can make a 120Hz or 144Hz panel report closer to 60Hz.
How it works
This test measures frame timing, not a monitor label
Modern browsers expose frame callbacks through the rendering loop. By timing those callbacks over several seconds, the page can estimate the active refresh rate your browser is actually receiving.
| Refresh rate | Frame interval | Typical use |
|---|---|---|
| 60Hz | 16.67 ms | Standard desktop and laptop displays |
| 75Hz | 13.33 ms | Entry gaming monitors |
| 120Hz | 8.33 ms | High refresh laptops and phones |
| 144Hz | 6.94 ms | Popular PC gaming monitors |
| 165Hz | 6.06 ms | Fast esports monitors |
| 240Hz | 4.17 ms | Competitive gaming displays |
| 360Hz | 2.78 ms | Extreme high refresh panels |
Troubleshooting
If the refresh rate test does not match your monitor spec
A monitor can be sold as 144Hz or 240Hz and still run at 60Hz if the computer, cable, dock, or operating system is using a lower mode. This page is designed for that practical question: what refresh rate is your browser actually receiving right now?
Start by checking the display settings in Windows, macOS, Android, or iOS. Then verify the browser window is on the screen you want to test. In multi-monitor setups, moving the window from a 60Hz laptop panel to a 144Hz external monitor can change the measured result. If the number still looks wrong, test without a dock, try another cable, reduce resolution temporarily, and rerun the test after each change.
System display mode
Make sure the operating system is set to the highest available refresh rate. Many monitors default to 60Hz after a driver update, cable change, or first connection.
Cable and dock bandwidth
High refresh rate at high resolution needs enough bandwidth. Some HDMI adapters, USB-C hubs, and docking stations cap the display at 60Hz even when the monitor supports more.
Browser timing
Browser animation timing is usually synchronized to the display, but energy saver modes, inactive tabs, remote desktop sessions, and screen mirroring can make the result lower.
Repeatable baseline
Record the result before and after each change. If the nearest standard rate, frame interval, and jitter improve together, you have likely found the limiting factor.
FAQ
Refresh rate test questions
How does this refresh rate test work?
The test samples requestAnimationFrame timing in your browser. When the browser is synchronized to the active display, the average frame interval can estimate the screen refresh rate in hertz.
Why does my 144Hz monitor show around 60Hz?
Common causes include the operating system being set to 60Hz, an HDMI or dock bandwidth limit, browser energy saving, screen mirroring, a background tab, or testing the wrong monitor in a multi-display setup.
How long should I run the monitor Hz test?
A few seconds gives a quick estimate, but a longer active-tab run is more stable. Close heavy apps, keep the tab visible, and compare repeated runs before changing hardware or settings.
Can this detect 120Hz, 144Hz, 240Hz, or 360Hz?
Yes, if the browser receives frames at those rates and the display path is not capped. Some browsers or devices may still fall back to 60Hz, so verify the system display setting too.
Is refresh rate the same as FPS?
No. Refresh rate is how often the screen can update. FPS is how often content produces frames. Smooth motion needs both the content and the display path to be stable.
Can I test a phone or tablet refresh rate?
Yes, but mobile devices often use adaptive refresh rates and battery limits. Test while the screen is active, compare power modes, and let the device cool down before repeated runs.
What is frame interval?
Frame interval is the time between visible updates. 60Hz is about 16.67 ms, 120Hz is about 8.33 ms, 144Hz is about 6.94 ms, and 240Hz is about 4.17 ms.
Is this a lab-grade monitor test?
No. This is a practical browser-based check for everyday diagnosis. It is useful for finding caps and configuration issues, but hardware certification requires specialized equipment.