Refresh Rate Testcheck your monitor's refresh rate in Hz, instantly
Detected refresh rate
—Hz
Keep this tab visible while it measures
- Current FPS
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- Average FPS
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- Frame time
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- Min / Max FPS
- — / —
- Jitter
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- Dropped
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Keys: Space/R retest · 1–3 speed · M mute · F full screen
What is refresh rate
How many new images your screen shows each second
Refresh rate, measured in hertz (Hz), is how many times per second a display redraws the picture. At 60Hz a new frame arrives every 16.7 ms; at 144Hz every 6.9 ms; at 240Hz every 4.2 ms. A higher rate means smoother scrolling, sharper motion and lower input lag, but only if your display is actually running at it. This refresh rate test checks exactly that.
- Hz in ten seconds
- The test starts on page load, times hundreds of frames, and locks a result snapped to a real display rate: 60, 120, 144, 240Hz and more.
- More than one number
- Frame time, jitter, min/max FPS, dropped frames and a stability rating show whether frames arrive evenly, not just how often.
- See the motion
- A UFO-style motion test at 1×, 2× and 4× speed, with px/frame and px/s readouts, lets you see the difference between 60Hz and high refresh.
- Private by design
- Everything runs in your browser. Your best rate and last eight results are saved on this device only, with no upload and no account.
How it works
How to test your refresh rate
Leave the tab visible, let it sample for ten seconds, and read the locked result. Change a display setting, then test again — no reload needed.
- 1
Open the page
The test starts on its own as soon as the page loads. Leave the tab in front and visible. A hidden or background tab is throttled by the browser, so the run starts over when you come back.
- 2
Let it sample for 10 seconds
The test times every frame your browser paints with requestAnimationFrame, which is locked to the display through V-Sync. The progress bar fills over ten seconds. The large number updates live while it runs.
- 3
Read the locked result
When the bar is full, the result locks. It shows the refresh rate in Hz, snapped to a real display rate such as 60, 120, 144 or 240, along with the raw measured value, frame time, jitter, dropped frames and a stability rating.
- 4
Check motion and retest
The moving saucer shows how smooth that rate looks at 1×, 2× or 4× speed. Press Test again (or R) after you change a display setting, and compare the result with the history strip saved on this device.
Tips for an accurate reading
- Close other tabs and heavy apps before testing. Background work steals frames and shows up as jitter.
- Keep the browser window on the monitor you want to measure. On multi-monitor setups, the browser usually syncs to the screen the window is on.
- Plug in laptops and switch off battery saver. Power-saving modes often drop the panel to 60Hz.
- Turn on hardware acceleration in your browser settings. Software rendering cannot keep up with high refresh rates.
- If you see 60Hz on a 144Hz monitor, check the refresh rate setting in your OS display settings first, then the cable.
- Use full screen (F) for the cleanest reading on desktop.
- Run the test twice. Two results that agree are more trustworthy than a single run.
FAQ
Refresh rates, answered
Straight answers about refresh rate, FPS, and getting an accurate reading from this free browser test.
What is a refresh rate test?
A refresh rate test measures how many times per second your screen draws a new image, in hertz (Hz). This one times the frames your browser paints for ten seconds and reports the rate (for example 60Hz, 144Hz or 240Hz), plus frame time, jitter and dropped frames. It is free and runs entirely in your browser.
How accurate is this refresh rate test?
On a visible tab with hardware acceleration on, the median frame interval is usually within a fraction of a percent of the real rate. You will see values like 143.98Hz or 59.94Hz, which snap to 144 and 60. Background load does not change the median much, but it does show up as dropped frames and lower stability.
Why does my 144Hz monitor show 60Hz?
Usually the operating system is still set to 60Hz, the cable cannot carry the higher rate, or a power-saving mode is capping it. Set the refresh rate in Windows Advanced display settings or macOS Displays settings, use DisplayPort or a high-speed HDMI cable into the graphics card, and plug in laptops. Then test again.
Is refresh rate the same as FPS?
No. Refresh rate (Hz) is how often the display can show a new image. FPS is how many frames your computer renders. To see 144 distinct frames per second, you need both a 144Hz display and at least 144 FPS. In a browser, animations are synced to the display, so FPS here normally matches Hz.
Does it work on phones?
Yes. Open the page on an iPhone, iPad or Android phone and the test starts on its own. 90Hz and 120Hz phones are detected correctly while they are plugged in or not in low-power mode. Adaptive screens drop their rate to save battery, so that is when a reading comes out lower.