Refresh rate test: find out what Hz your screen is really running at
The refresh rate test measures how many times per second your browser can draw a new frame, which on a healthy system equals the display’s refresh rate in hertz (Hz). It samples several seconds of frame timings, takes the median, and matches it to a standard rate such as 60, 90, 120, 144 or 240 Hz.
Use it after buying a high-refresh monitor or phone to confirm you get 120 or 144 Hz and not the 60 Hz default, after changing a cable or driver, or to see whether a laptop on battery has dropped its rate. The graph shows frame pacing and the motion test makes skipped frames visible.
This is an FPS test for your screen, not for games: a browser page cannot see the frame rate of a game or other app (see the limits below). Everything runs locally; nothing is installed or sent.
How to use the Refresh Rate Test
- Keep this tab in the foreground and hands off the mouse while the progress bar fills.
- Read the detected rate in the result panel, with the median frame time and whether it matched a standard refresh rate.
- Check the live graph: a flat line means steady pacing; red ticks mark long frames.
- Run the motion test at a chosen speed; the bar should glide, not jump.
- If the result is below your monitor’s rating, change the rate in display settings and press Measure again.
Refresh Rate Test features
Median-based detection
requestAnimationFrame timings are summarised by their median, which is more robust than an average when a few frames are late.
Standard-rate matching
Results within 3 % of a common rate (24 to 500 Hz) snap to it; others are shown as measured.
Live frame-time graph
The last 300 frame times with reference lines for 60, 120, 144 and 240 Hz and red markers for dropped frames.
Motion and frame-skip test
A moving bar with ghost trails and a 16-square frame counter you can photograph to catch skipped frames.
Pause-aware and phone friendly
Measurement restarts if the tab goes to the background, where browsers throttle animation; 90 and 120 Hz phones work too.
How the refresh rate is measured — and why 60 Hz might show on a 144 Hz monitor
Browsers call requestAnimationFrame once per display refresh, so the time between calls is one frame: 16.67 ms at 60 Hz, 8.33 ms at 120 Hz, 6.94 ms at 144 Hz, 4.17 ms at 240 Hz. The test records those intervals, takes the median and converts it to Hz. If the browser cannot keep up you see long frames, so dropped frames are reported next to the median.
A high-refresh panel reporting 60 Hz is almost always a settings issue: Windows and macOS often default to 60 Hz on a new monitor, HDMI 1.4 cables and some docks cannot carry 1440p above 60 Hz, laptops drop to 60 Hz on battery, and with two monitors Chrome and Edge sometimes animate at the lower rate.
| Refresh rate | Frame time | Typical use |
|---|---|---|
| 60 Hz | 16.67 ms | Most monitors, TVs and older phones |
| 75 Hz | 13.33 ms | Budget gaming monitors |
| 90 Hz | 11.11 ms | Mid-range phones, VR headsets |
| 120 Hz | 8.33 ms | Flagship phones, iPad Pro, gaming TVs |
| 144 Hz | 6.94 ms | Mainstream gaming monitors |
| 165 / 180 Hz | 6.06 / 5.56 ms | Overclocked 144 Hz-class panels |
| 240 Hz and above | ≤ 4.17 ms | Esports monitors |
Change the refresh rate on Windows, macOS, Android and iPhone
- Windows 11: Settings → System → Display → Advanced display → “Choose a refresh rate”. Windows 10: Advanced display settings → Display adapter properties → Monitor tab.
- macOS: System Settings → Displays → Refresh Rate. Choose a fixed rate rather than ProMotion for a steady result.
- Android: Settings → Display → Refresh rate (or “Motion smoothness” on Samsung). “Adaptive” modes change rate with content, so the measured value may vary.
- iPhone / iPad with ProMotion: the rate adapts from 10 to 120 Hz automatically; Safari usually animates at up to 120 Hz. Low Power Mode caps it at 60 Hz.
What a browser can and cannot measure (FPS tests, VRR and power saving)
With G-Sync, FreeSync or Adaptive-Sync enabled, the display refreshes whenever a frame is ready, so browser frame times may not line up with a fixed rate and the test can report an in-between number such as 97 Hz. Energy-saving features (battery saver, Chrome’s energy saver, Low Power Mode) can hold the browser at 60 Hz, disabled hardware acceleration can cap it too, and virtual machines or remote desktops are limited, so the test only reports what the browser actually draws.
Searches for an “FPS test” often mean in-game FPS. A web page cannot read the frame rate of a game, a video player or another app, and cannot read the true panel refresh beyond what the browser renders; use the game’s own counter or a driver overlay for that, and see the frame time calculator to convert FPS to milliseconds. Background tabs are throttled, so keep this one visible.
Once confirmed, use the Dead Pixel Test to check the panel itself and the Screen Resolution Checker to confirm the resolution and pixel density.
Refresh Rate Test FAQ
How accurate is this refresh rate test?
On a normally loaded device the median frame time matches the panel rate to within about 1 %. Heavy load, a VRR display or power saving can make the browser draw slower than the panel refreshes; the test then shows what the browser achieved and the likely cause.
My monitor is 144 Hz but the test says 60 Hz. Why?
The operating system is probably set to 60 Hz. Change it in display settings, check the cable supports the rate, plug in a laptop charger, then press “Measure again”.
Does the test work on phones?
Yes. Open it on an Android phone or iPhone; 90 and 120 Hz screens are detected, though adaptive-refresh phones may show a lower rate.
What does “long frames” mean?
A frame that took more than 1.5× the median, so the browser missed a refresh. A few are normal; many mean the system is busy, so close other apps and run it again.
Why does the result change between runs?
Small changes are measurement noise. Large swings usually mean variable refresh rate, adaptive phone displays, or power management; try the 10-second measurement.
Can this show my FPS in a game?
No. It measures how fast this browser tab draws frames, which equals the display rate on a normal system. In-game FPS needs the game’s own counter or a driver overlay.