Frame Skipping Test

Run a free frame skipping test online. Watch a moving bar flash on every dropped frame and see your refresh rate, skip rate, and a plain-language jank score.

Keep this tab in the foreground while the test runs. Switching tabs or apps pauses your browser's rendering and will throw off the skip count.

Press Start. The bar begins moving immediately while frame timing runs in the background.

See Every Dropped Frame While It Happens

Smooth motion on a screen depends on every frame arriving right on schedule. When your browser or graphics driver falls even slightly behind, a frame gets skipped and the same image holds for an extra cycle, something you usually only feel as a vague stutter. This test times every single frame instead of just an average, so you can see precisely how often that happens and how bad it gets.

Why Run a Frame Skipping Test?

Frame-By-Frame Timing

Every frame is timed against the last one using the browser's own animation clock, not a rough average.

Auto-Detected Refresh Rate

The test works out your screen's real refresh rate on the fly, whether it's 60Hz, 120Hz, or 144Hz.

Live Skip Flashes

The moving bar flashes the instant a skip is detected, so you can match what you see with what gets logged.

Plain-Language Score

Stop anytime for a skip rate, longest stall, and a jank rating you don't need a manual to understand.

How this Frame Skipping Test works

Every monitor redraws its screen at a fixed rate — 60, 120, or 144 times each second. A frame skip happens when your browser can't finish drawing in time for that redraw, so the same image repeats for an extra cycle before catching up. You rarely notice a single skip, but string enough of them together and smooth motion turns into a visible stutter.

This test puts a bar in constant motion across a track and times every frame using the browser's own animation clock rather than a fixed interval. As it runs, it watches how fast frames normally arrive to work out your real refresh rate, since that number is different on a 60Hz laptop screen than on a 144Hz gaming monitor. From there, any frame that takes noticeably longer than expected gets logged as a skip, and the bar flashes red the instant it happens so you can match what you see with what the timer recorded.

While the test runs, you get a live count of frames rendered, frames skipped, the skip rate as a percentage, and the longest single stall in milliseconds. Stopping the test turns those numbers into a plain score, from smooth to heavy jank, based on how often frames were actually missed rather than a single average reading.

Everything happens locally in your browser tab using requestAnimationFrame. No video, timing data, or device information is sent anywhere, and switching away from the tab or closing it stops the test immediately.

How to use this Frame Skipping Test

1

Start the test

Press Start and the bar begins moving immediately while frame timing runs quietly in the background.

2

Watch for red flashes

Every time a frame takes too long to arrive, the bar flashes red and the skip counter ticks up in real time.

3

Stop for your score

Stop anytime to see total frames, skip rate, longest stall, and a plain-language jank rating.

Frequently Asked Questions

What exactly counts as a "skipped frame" in this test?
A skipped frame is a moment when your screen was due for a fresh image, based on its normal refresh rate, but the previous frame stayed on screen for an extra cycle because the browser wasn't ready in time. The test finds these by comparing the time between frames against your monitor's typical redraw interval, which it works out automatically while it runs.
How does the test know my monitor's refresh rate without me entering it?
It watches the natural gaps between frames while the bar moves and treats the shortest, most consistent gaps as the true refresh interval, since a skip can only make that gap longer, never shorter. This means a 60Hz laptop screen and a 144Hz gaming monitor are both detected correctly without any manual setting.
Is a skip rate of 1% or 2% something to worry about?
No. A small percentage of skips is normal even on capable hardware, since background processes and operating system tasks occasionally interrupt rendering for a moment. Skip rates under about 3% usually aren't noticeable during normal use. Rates climbing into double digits are worth investigating.
Why do I see more skips when other tabs or apps are open?
Every open tab and background app competes for the same CPU and GPU time your browser needs to redraw the bar on schedule. Video calls, other animated pages, and heavy downloads running in the background are common causes of a higher skip rate.
Does switching to another tab during the test count against my score?
No. Browsers slow down or pause rendering almost entirely in background tabs to save power, which would otherwise show up as one huge fake stall. The test treats unusually long gaps like this as a pause rather than counting them as skipped frames.
Can an older or weaker graphics chip cause frame skipping?
Yes. Hardware that struggles to finish rendering work within a single refresh interval will show a higher skip rate, and this becomes more visible at higher refresh rates like 120Hz or 144Hz, which give the browser far less time per frame than a standard 60Hz screen.
Why does frame skipping matter more for gaming than for regular browsing?
Fast motion, like tracking a moving target in a shooter or panning a camera, makes any inconsistency in frame timing much easier to notice. A skip that would go unseen while reading a page can feel like a stutter or a missed shot in a fast game.
Is this the same thing as the FPS counter shown in games?
It measures something similar, but where a game's FPS counter usually reports one average number per second, this test looks at the timing of every single frame, which catches individual skips that an average can easily hide.
Will running this test heat up my device or drain the battery quickly?
No. Moving a single bar across the screen is a light task for any device, nothing like a GPU stress test. Expect normal battery use, not the fan noise or warmth you might see from a heavier benchmark.
Can I compare my skip rate with someone using a different device?
You can compare loosely, but treat it as a rough guide rather than an exact benchmark. Screen refresh rate, browser, and how many other programs are running all affect the result, so comparing the same device and browser over time gives a fairer picture.
Does closing the tab stop the test right away?
Yes. The test only runs while the page is open, so closing the tab or navigating away stops it immediately, with nothing left running in the background.

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