Frame Rate Test — Check Your Monitor's Real FPS Online

This frame rate test measures how many frames per second your screen is actually delivering, live, in your browser. Watch the moving pattern, read the figure, and you have an honest check of your display's smoothness in about ten seconds. It is the quickest way to confirm that a monitor sold as 120 Hz or 144 Hz is really running that fast, to compare two screens, or to see whether your hardware is keeping up. Nothing to install, nothing to sign up for.

What the three readings mean

The test reports three figures. Read together, they tell you what your display is doing and whether the test itself is keeping pace.

Screen resolution

The pixel dimensions of your display, scaled by its device pixel ratio, so a high-density screen reports its true native figure rather than a CSS approximation. Resolution does not affect smoothness by itself, but it affects frame rate: more pixels per frame is more work, so a very high resolution can pull your FPS down on the same hardware.

Screen FPS

The headline number — the frames per second your browser is actually rendering to the display. On a healthy setup this sits close to your panel's refresh rate: around 60 on a 60 Hz screen, 120 on a 120 Hz screen, 144 on a 144 Hz screen. If it lands well below your rated refresh rate, the bottleneck is upstream of the panel, and the section on why your FPS is lower than your refresh rate below covers the usual causes.

Test FPS

The rate the test's own animation is running at. The Canvas FPS control lets you cap this deliberately — useful for slowing the motion down and studying individual frames. If you have not touched that control, this figure should track your Screen FPS closely. If it sits well below, the page itself is being starved, usually by background load or a busy tab.

How to get an accurate reading

The test starts as soon as the page loads and updates continuously. A few steps make the number trustworthy:

• Set your screen to its highest refresh rate first, in your operating system's display settings, so the test can reach the panel's real ceiling. Windows and macOS both ship new displays at a lower default more often than people expect. Our guide on how to check your refresh rate walks through it.
• Go fullscreen using the button below the canvas. This removes browser chrome and other page elements and gives the cleanest reading.
• Close heavy background tabs. Video calls, streaming, and anything running WebGL will compete for the same GPU.
• Plug a laptop in. Battery-saver modes throttle the GPU and cap refresh rate, often silently.
• Let it settle for a few seconds before you trust the figure.
• Try both motion modes. Classic sweeps two rectangles across the canvas; Landscape scrolls a pixel-art scene that changes with the time of day. Both advance a fixed number of pixels per frame, so motion stays perfectly even and any unevenness you see is your display, not the test.

Frame rate, FPS and refresh rate

Three numbers govern motion and they are easy to confuse. Frame rate, written as FPS, is how many images your system produces each second. Refresh rate, measured in hertz, is how many times your screen can physically redraw itself each second. They interact, and the lower one sets the limit: a graphics card rendering 200 FPS on a 60 Hz panel still shows 60, while a 144 Hz screen fed 40 FPS simply repeats frames.

Frame time is the same information expressed as duration — how many milliseconds each frame gets. It is often the more useful way to think about it, because the gap between 60 and 120 FPS is much larger than the gap between 120 and 240, and frame time makes that obvious at a glance:

Dropping from 60 to 30 FPS costs you 16.7 ms per frame. Going from 144 to 240 buys back 2.7 ms. That is why the jump from 60 to 120 feels dramatic and the jump from 144 to 240 feels subtle.

Why is my FPS lower than my refresh rate?

This is the most common reason people run a frame rate test, and a 144 Hz monitor reading 60 is almost never a broken panel. Work through these in order:

• The display is not set to its maximum refresh rate. By far the most frequent cause. Windows and macOS often default a new monitor to 60 Hz even when it supports much more, and nothing in the interface tells you.
• Hardware acceleration is off in your browser. Without it, rendering falls back to the CPU and frame rate collapses. In Chrome it is under Settings → System.
• The cable or port is the limit. High refresh rates at high resolutions need the bandwidth of DisplayPort or a recent HDMI revision. An older cable will silently negotiate down to 60 Hz.
• A power-saving mode is throttling you. Laptops on battery routinely cap refresh rate to extend runtime, and a hot machine will slow down regardless of what it is plugged into.
• The browser is throttling its own animation. Some browsers limit background or inactive tabs to a lower rate. Keep the test tab focused and in the foreground.
• VSync or a frame cap is holding it there on purpose. A reading pinned to exactly 60 is usually capped, not struggling.

If the figure looks correct but motion still feels rough, the cause is frame consistency rather than raw speed. An average that reads a steady 120 while dropping the occasional late frame will still hitch, because smooth motion depends on even frame timing, not just a high count. The stutter test exposes that directly.

How this test measures your frame rate

The test hooks into requestAnimationFrame, the browser's own animation callback, which fires once per display refresh cycle. Counting those callbacks over a short window gives the frames per second your browser is genuinely delivering.

Two honest caveats. First, because a browser composites its own output, this is a close estimate rather than a laboratory measurement — accurate enough to verify a refresh rate, compare two screens and diagnose a problem, but not a substitute for an oscilloscope. Second, this measures browser frame rate. It reflects your display and your system's rendering path, but it is not a game benchmark; for in-game FPS you want an overlay such as your game's own counter or a monitoring tool.

Beyond frame rate: the rest of the motion picture

A high frame rate is necessary for smooth motion but it is not sufficient. Several other display traits decide how good a screen actually looks while things move, and each has its own test here.

• Motion blur test — even at a perfect frame rate, a screen smears moving detail, because each frame is held static while your eyes keep travelling. This measures that persistence blur and any ghosting.
• Frame skipping test — some panels quietly drop frames they claim to display, especially when overclocked. A camera-based pattern catches what software cannot.
• Screen tearing test — when frames arrive out of sync with the refresh, the image splits along a moving horizontal line. Confirms whether VSync or variable refresh rate is doing its job.
• Stutter test — a live frame-time graph and jank counter reveal the late frames a high average hides.
• Scrolling smoothness test — scrolling is the motion you meet most often, and this measures how evenly your browser delivers it.

Frequently asked questions

How do I know if my monitor is really 144 Hz?

Set your display to 144 Hz in your operating system's settings, then run this test in fullscreen with other tabs closed. A Screen FPS reading close to 144 confirms the panel is delivering it. If it reads 60, work through the causes above — the cable and the OS refresh rate setting account for most cases.

Is this frame rate test accurate?

It is an accurate estimate. It measures the frames per second your browser renders, which closely tracks your display's real output. Because the browser composites its own frames, it is not a laboratory reading, but it is reliable enough to verify a refresh rate, compare two screens and diagnose performance problems.

What is a good frame rate?

60 FPS is the accepted baseline for smooth, responsive motion. Gamers target 120, 144 or 240 on high-refresh monitors, while cinema runs at 24 and looks fine because of how it is shot. The right target depends on your display and what you do with it; our guide on what frame rate is covers the trade-offs.

Does a higher frame rate always look better?

Only up to your monitor's refresh rate. Rendering 200 FPS on a 60 Hz screen burns power for no visible gain, because the panel can only show 60. Match your target to the display you own, and confirm what it supports with our refresh rate guide.

Does this test work on a phone?

Yes. It is a useful way to check whether a phone advertised at 90 or 120 Hz is running at that rate — many drop to 60 on battery saver, or switch adaptively depending on what is on screen.

Why does my FPS keep changing?

Small fluctuation is normal; the figure is sampled over a short window and background activity moves it. Large swings suggest something is competing for the GPU, or that a variable refresh rate feature is adjusting the panel on the fly.

Related tests and guides

• Motion blur test — how sharp your screen keeps moving detail.
• Frame skipping test — whether the panel draws every frame.
• Screen tearing test — whether frames align with the refresh.
• Stutter test — frame-time consistency and jank.
• Scrolling smoothness test — everyday scroll jank in your browser.
• What is frame rate? — the fundamentals of FPS and Hz.
• What is my refresh rate? — find and confirm your screen's Hz.
• Frames per second in gaming — why FPS matters for play.

More display tests

Frame rate is one way a screen can fall short. DeadPixelTest.org fills your display with solid colours so you can find dead, stuck or hot pixels before a return window closes, and includes a fixer that flashes rapid colours to try to revive a stuck one. BackLightBleedTest.org shows a pure black screen so you can judge backlight bleed and IPS glow — the uneven light that leaks around the edges of an LCD in dark scenes, best assessed in a dark room.