Refresh Rate Test
Detect the refresh rate your browser is really running at, then see it in motion.
Detected refresh rate
… Hz
Sampling frames for 5 seconds…
Motion clarity demo
The bars move at your detected frame rate. Higher refresh rates show visibly smoother motion and less ghosting — compare by eye while tracking a bar.
How it works
Browsers repaint in sync with your display, so timing repaints reveals the refresh rate. The test
samples requestAnimationFrame timestamps for five seconds and takes the
median frame interval — a method that shrugs off the occasional stutter or dropped
frame that would skew an average. The result is then snapped to the nearest standard rate (60, 75, 90,
120, 144, 165, 240…) when it's within 3%, since measurement noise of a fraction of a hertz is normal.
Two honest caveats. First, the browser measures the rate the OS is driving the display at — if Windows is set to 60Hz, a 144Hz monitor reads 60Hz here (our refresh rate guide shows where to change it). Second, power saving matters: on battery, many laptops drop the panel rate and browsers throttle animation frames, so plug in before measuring. The motion demo animates bars at your detected rate — the difference between 60Hz and 144Hz is immediately obvious when your eye tracks a moving bar.
Troubleshooting
› It reports 60Hz but my monitor is 144Hz
The OS may be running the display at 60Hz — check the refresh rate in display settings, not just the monitor spec. Laptops on battery and some browsers also throttle to save power.
› The number fluctuates slightly
Small variance (e.g. 143.9–144.1) is normal measurement noise. Large drops mean the browser is skipping frames — close heavy tabs and disable battery-saver mode, then re-run.
Frequently asked questions
› How accurate is the detected Hz?
Within about 1Hz on an unloaded system. We sample thousands of animation frames and use the median interval, which is robust to occasional stutters.
› Why does my 144Hz monitor read 60Hz?
Your OS is probably driving it at 60Hz — the monitor spec is the maximum, not the current mode. Set the refresh rate in display settings and re-run.
› Does battery saver affect the result?
Yes. Browsers throttle animation on low-power modes, and some laptops drop the panel to 60Hz on battery. Plug in for a true reading.