LIVE DIAGNOSTIC
Input stays in this pageMonitor refresh-rate estimate
Keep this tab visible, stop heavy background activity if possible, then run a three-second measurement.
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NovaTools / NovaTools Test Lab / Refresh Rate Test — Check Monitor Hz Online
DISPLAY Hz TEST · PLAYER TOOL
Refresh Rate Test — Check Monitor Hz Online
Estimate the refresh cadence available to this browser tab. The test samples requestAnimationFrame timestamps and reports estimated Hz, median frame interval, timing jitter and sample count.
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What the refresh-rate test reports
- Estimated refresh rate in Hz
- Median frame interval in milliseconds
- Average frame interval
- Timing jitter across the sample
- Number of animation frames measured
- Nearest common refresh-rate class when the estimate is close
How to interpret the result
requestAnimationFrame callbacks generally follow the display refresh cycle, so stable measurements often land near common rates such as 60, 120, 144, 165 or 240 Hz. Small deviations are normal. A large mismatch may indicate a different OS display mode, browser throttling or unstable frame delivery.
QUICK WORKFLOW
How to use this test
Use repeatable conditions. One browser result is a diagnostic clue, not a complete hardware verdict.
01
Keep the page visible
Background tabs are commonly throttled and will produce misleading results.
02
Run the measurement
Press Measure refresh rate and avoid switching windows for a few seconds.
03
Compare your display setting
Check whether the estimate is close to the refresh rate selected in your operating system or GPU settings.
04
Repeat if needed
Variable refresh, power saving and load can change timing. Repeat after closing heavy applications if the result is unstable.
METHOD & LIMITATIONS
Technical reference: MDN — requestAnimationFrame() ↗What the browser can — and cannot — tell you
This is a browser timing estimate, not a hardware oscilloscope measurement. Variable refresh rate, compositor behavior, power saving, remote desktop, multi-monitor setups and system load can affect the callback cadence.
Common questions
Why does a 144 Hz monitor show a slightly different number?
Frame timestamps are not perfectly uniform. Browser scheduling and display timing can produce small differences around the configured refresh rate.
Why does the test show about 60 Hz on a high-refresh monitor?
Check the operating-system display refresh setting, the active monitor, cable/port capabilities, power-saving settings and whether the browser window is actually on the high-refresh display.
Does this measure FPS in my games?
No. It estimates browser repaint cadence. Game FPS depends on the game engine, GPU, CPU, settings and frame pacing.
Does the test work in a background tab?
It should not be trusted there. Browsers commonly pause or throttle requestAnimationFrame in hidden tabs.