Display timing measurement
Refresh Rate Test
Estimate the display refresh rate seen by this browser, including frame interval, jitter, and common Hz matching.
Refresh Rate Test
Run measurement
Keep this tab visible and avoid moving the window while the sample runs. Variable refresh rate and power saving can change the result.
What this tool measures
The browser schedules animation frames in step with the compositor. Measuring many frame intervals provides an estimate of the refresh rate available to the page.
How to use it
- Keep this tab visible.
- Start the sample and avoid resizing or switching tabs.
- Compare the measured value with common rates such as 60, 120, 144, 165, or 240 Hz.
When to test refresh rate
- Verify a new high-refresh-rate monitor
- Recheck settings after changing a cable or graphics driver
- Investigate browser animation that feels capped at 60 Hz
How to verify 144 Hz or 240 Hz
A value near the selected display mode with stable frame intervals usually means the browser is receiving animation frames at that rhythm.
Repeat the test
Use several runs under the same conditions before drawing a conclusion from a single value.
Compare like with like
Keep the browser, window size, device connection, and power mode consistent when comparing results.
Check the frame interval
60 Hz is about 16.67 ms, 120 Hz 8.33 ms, 144 Hz 6.94 ms, and 240 Hz 4.17 ms per frame.
The result stays near 60 Hz
Check the operating-system display mode, video connection, monitor menu, browser power saving, and laptop power profile.
Measurement limits
This is a browser-side estimate, not a direct monitor firmware reading. Power saving and variable refresh rate can change it.
Privacy
Measurements are calculated locally in your browser and are not uploaded by the tool.
Why the measured refresh rate looks wrong
Keep the page active
Background-tab throttling, browser extensions, and other busy applications can affect browser measurements.
Retest under controlled conditions
Reload the page, keep the same settings, and repeat the measurement before treating an outlier as a fault.
Keep the tab in the foreground
Browsers throttle animation in background tabs, so the page must remain visible while sampling.
Small fluctuations are normal
Variable refresh rate, compositor scheduling, and system load can cause minor movement. Prioritize the median interval and nearest common mode.
Refresh rate questions
Is this a hardware certification test?
No. It is a browser-side diagnostic intended for comparison and troubleshooting, not laboratory certification.
Where is the test data processed?
The measurement is calculated in this browser tab and the tool does not upload the raw test input.
Why is the result not exactly 144.00 Hz?
Browser timing contains jitter and display clocks can differ slightly. Being consistently close to the target matters more than matching every decimal.
Does this read the monitor specification directly?
No. It estimates the refresh rhythm visible to the browser from requestAnimationFrame timing.