120Hz test
Find out whether your screen is actually showing 120 frames per second. Frame time at 120 Hz is 8.33 ms.
Estimated refresh rate
… Hz
- Target frame time
- 8.33 ms
- Measured frame time
- ms
- Long frames (last 240)
Top lane updates at 60 fps, bottom at 120 fps (capped at whatever your display actually shows). If both look the same, you are not getting 120 Hz. For a detailed graph see the full refresh rate test.
Who has 120 Hz displays
Many gaming laptops, recent phones and tablets, consoles on 120 Hz TVs, and Apple ProMotion displays.
Getting 120 Hz working
- Pick 120 Hz in the OS. Windows 11: Settings → System → Display → Advanced display → Choose a refresh rate. macOS: System Settings → Displays → Refresh Rate.
- Cable and port: 1080p and 1440p at 120 Hz commonly work over HDMI 2.0 or DisplayPort 1.2+. 4K at 120 Hz needs HDMI 2.1 or DisplayPort 1.4 (sometimes with DSC).
- In games, set the in-game refresh rate (if offered) to 120 Hz and make sure the frame rate cap isn't lower.
Phones and ProMotion screens vary their refresh rate to save power, so a browser may read lower than 120 while the screen is idle. Scroll or move the mouse to wake it up.
Other refresh rates: 60Hz test · 75Hz test · 144Hz test · 165Hz test · 240Hz test · 360Hz test
Questions people ask
How do I know if my monitor is running at 120 Hz?
Open this page and wait a few seconds. If the estimate settles near 120 Hz, the browser is receiving 120 frames per second from your display. You can also check Windows Settings → System → Display → Advanced display, or macOS System Settings → Displays → Refresh Rate.
Why does my 120 Hz monitor show a lower number?
Phones and ProMotion screens vary their refresh rate to save power, so a browser may read lower than 120 while the screen is idle. Scroll or move the mouse to wake it up. Also check that the cable goes into the graphics card rather than the motherboard, battery saver is off on laptops, and hardware acceleration is on in the browser.
What cable do I need for 120 Hz?
1080p and 1440p at 120 Hz commonly work over HDMI 2.0 or DisplayPort 1.2+. 4K at 120 Hz needs HDMI 2.1 or DisplayPort 1.4 (sometimes with DSC). Exact limits depend on resolution, colour depth and whether the monitor uses Display Stream Compression (DSC), so check your monitor's manual.
Is a browser refresh rate test accurate?
It estimates refresh from requestAnimationFrame timing, which browsers align to the display. It reliably separates 60, 120, 144 and 240 Hz, but it is not a lab measurement, and variable refresh (G-Sync, FreeSync, ProMotion) can move it.