ScreenVitals
Live browser frame timing

Check your active refresh rate and inspect motion.

Measure animation-frame timing in your browser, then use a pursuit pattern to look for visible trailing, stutter, and overshoot.

FreeAbout 1 minuteRuns locally
No sign-up · Nothing uploaded

How to run this test

  1. Keep this tab active

    Close heavy tabs and keep the browser visible. If you use multiple monitors, move the window fully onto the display being tested.

  2. Run the live measurement

    The test samples animation frames and reports the median timing. A short warm-up reduces one-off loading effects.

  3. Watch the moving target

    Follow the target with your eyes. Look for duplicate edges, dark or bright trails, uneven steps, or periodic stutter.

  4. Verify system settings

    If the result is lower than expected, check the operating-system refresh-rate setting, cable, port, GPU driver, power mode, and browser.

How to interpret what you see

Measured refresh—Press measure to begin
ScreenVitals

What the result means

The number is an estimate of the browser’s active animation rate, not a hardware-certified measurement. A steady value close to the selected display mode is the expected result. Visible trails are influenced by pixel response, overdrive, sample-and-hold blur, camera behavior, and how your eyes track motion.

Important limitation

ScreenVitals provides a controlled visual aid. Results depend on your panel, brightness, viewing angle, room lighting, browser, and—when photos are used—camera exposure. It does not replace manufacturer testing or calibrated measurement equipment.

Questions about this test

Know what the pattern can—and cannot—tell you.

Why is the measured value slightly below 60, 120, or 144 Hz?

Browser scheduling and timer precision introduce small variation. Values such as 59.9, 119.9, or 143.9 can be normal. Background tabs, power saving, remote desktop, and heavy browser extensions can affect the estimate.

Can a website measure monitor response time in milliseconds?

Not accurately without a high-speed camera or measurement hardware. Browser motion patterns can reveal visible trailing and overshoot, but they cannot provide a certified gray-to-gray response time.

Why does the browser report 60 Hz on my high-refresh monitor?

Check the operating-system display setting, cable and port capabilities, GPU settings, power mode, browser window location in a multi-monitor setup, and whether remote-desktop or battery-saving features are limiting refresh.

Is screen tearing the same as low refresh rate?

No. Tearing occurs when parts of different frames appear at once because presentation and display refresh are not synchronized. Refresh rate, frame rate, V-Sync, VRR, browser composition, and GPU settings can all affect what you see.

Does the motion test work on phones?

Yes in modern mobile browsers, although power saving, adaptive refresh, touch inactivity, and browser UI can change the active refresh rate during the test.

Continue your screen check

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