Monitor Refresh Rate Test (Hz)
Find out how many times per second your screen really refreshes. The test starts automatically, measures every frame your browser draws and shows your refresh rate, frame times and any skipped frames.
The UFO moves a fixed distance each frame. Smooth, even motion means no skipped frames. The squares in the strip below it light up one per frame: a gap or a doubled square means a frame was skipped or repeated.
How to use the Monitor Refresh Rate Test (Hz)
- Open the page on the monitor you want to test and keep the browser window there.
- Wait three seconds without switching tabs while the test measures frames.
- Read your refresh rate in the big number, with the exact measured value below it.
- Watch the motion test: the UFO should glide smoothly and the dropped frame counter should stay near zero.
- Press Restart test after changing display settings, or Copy result to share the reading.
Common refresh rates and frame times
| Refresh rate | Frame time | Typical devices |
|---|---|---|
| 60 Hz | 16.67 ms | Most office monitors, laptops and TVs |
| 75 Hz | 13.33 ms | Budget monitors with a small boost |
| 90 Hz | 11.11 ms | Some phones and VR headsets |
| 120 Hz | 8.33 ms | Recent phones, tablets, MacBook Pro ProMotion, gaming TVs |
| 144 Hz | 6.94 ms | Mainstream gaming monitors |
| 165 Hz | 6.06 ms | Gaming monitors and laptops |
| 240 Hz | 4.17 ms | Competitive esports monitors |
| 360 Hz | 2.78 ms | High-end esports monitors |
Frame time is simply 1000 ÷ refresh rate. Halving the frame time is why 120 Hz feels noticeably smoother than 60 Hz in scrolling and fast games.
When the browser reports a lower rate
- Battery saver and low power mode on laptops and phones often cap browser animations at 60 Hz or 30 Hz.
- Background tabs and minimized windows are paused or slowed to about 1 frame per second, so keep this tab visible during the test.
- Multi-monitor setups may sync the browser to the primary screen. Move the window to the screen you want to test and restart.
- Remote desktop, screen sharing and virtual machines usually deliver 30 to 60 frames per second regardless of the physical screen.
- Cables and ports limit what the monitor receives. High rates at high resolutions need DisplayPort or HDMI 2.0/2.1.
How to set your refresh rate
Windows 11: Settings, System, Display, Advanced display, then choose a refresh rate. macOS: System Settings, Displays, then pick a refresh rate for the selected display. Android and iPhone: high refresh is usually automatic; on Android look for Smooth display or Motion smoothness under display settings. After changing the setting, press Restart test to confirm the new rate.
How accurate is a browser refresh rate test?
The browser hands each animation frame a timestamp that is aligned with the display's vertical refresh, so averaging a few hundred frames gives a very accurate rate, typically within a few hundredths of a hertz. Single frame times vary slightly because of timer rounding and system load, which is what the jitter value shows. The test ignores the first frames while the page settles and ignores gaps longer than a quarter of a second, such as when the tab was hidden, so a brief interruption does not spoil the result.
Frequently asked questions
How does this refresh rate test work?
Browsers draw animation frames in sync with the display, using requestAnimationFrame. The test records the time between hundreds of frames, takes the typical (median) frame interval, averages the frames close to it and converts that to Hz. A 144 Hz screen gives frames about 6.94 ms apart.
Why does it show 60 Hz on my 144 Hz monitor?
Check that the monitor is set to 144 Hz in your operating system's display settings, that the cable supports it (many HDMI 1.4 cables and ports top out at 60 Hz at high resolution), and that the browser window is on that monitor. Battery saver modes on laptops also often limit browsers to 60 Hz or lower.
Why is the measured value not exactly 60 or 144?
Real displays run at slightly different rates, such as 59.94 Hz or 143.98 Hz, and browser timers are rounded for privacy. The big number shows the nearest standard rate; the measured value shows exactly what the browser saw.
What are dropped frames?
A frame is counted as dropped when the gap between two frames is more than one and a half normal frame times. Occasional drops are normal when the computer is busy. Regular drops mean the browser or graphics card cannot keep up, which shows as stutter in the motion test.
Does the test work with multiple monitors?
It measures the monitor the browser window is on. If your screens run at different rates, move the window to the other screen and press Restart test. Some systems sync the browser to the main monitor, so mixed setups can report the lower rate.
Can a browser measure variable refresh rate (G-Sync / FreeSync)?
Variable refresh rate adapts to the frame rate of games. Browsers usually still render at the display's maximum fixed rate, so this test shows the maximum rate rather than VRR behaviour.