Waiting for a full second of frames
Display scale: 0–240 FPSUpdates once a second. Browser timing is an estimate, not a measurement of your panel's rated refresh rate or VRR status.
The live reading, motion lanes and timing charts describe different parts of the same browser session. Keep them visible together to connect a change in the numbers with what you actually see moving.
The page counts requestAnimationFrame callbacks and updates the reading once a second. Those callbacks are often scheduled in step with display presentation, but browser policies, background tabs, load and power settings can change their frequency. Treat the result as current browser behavior, not an independent measurement of the panel's rated refresh rate.
Frame-rate history keeps the latest 30 one-second samples. The frame-time chart shows the latest 60 intervals between callbacks. Short, similar intervals indicate consistent callback timing during that sample. Red bars mark intervals longer than 20 milliseconds; that fixed visual marker is a guide, not a universal pass or fail threshold.
The blocks travel at 60, 120 and 240 CSS pixels per second. Follow one with your eyes and compare the appearance of its edges against the other lanes. Speed changes how far an object travels between frames, so the faster lane may reveal blur more readily. This visual comparison does not measure gray-to-gray response time or certify an overdrive setting.
Keep the tab in front, wait several seconds and avoid opening busy applications while comparing readings. Check the refresh setting for the display in your operating system, especially when using more than one monitor. Pause to inspect a snapshot or restart to clear the session. Returning from a hidden tab begins a fresh sample window.
A lower reading can reflect browser scheduling, graphics load, a remote desktop session or a power-saving policy. Compare the same browser on the intended display and check the system's active display mode. Cable and adapter capabilities depend on the complete connection and selected format; a browser reading alone cannot identify the limiting component.
Hertz describes a display refresh frequency, while FPS describes a stream of frames. The duration of one ideal refresh interval is 1000 divided by the rate: 60 Hz is about 16.67 ms, 120 Hz about 8.33 ms and 144 Hz about 6.94 ms. Consistent timing matters alongside the average. This page does not determine whether VRR is active.
Browser load, foreground state and system load affect sampling. Compare with your system display settings.
Confirm the intended refresh rate in system settings.
Keep the page in the foreground and close demanding applications.
Compare motion patterns with your normal use cases.
Patterns support visual inspection. Quantitative color accuracy, brightness, gamut coverage and response time require appropriate instruments and methods.
No. It provides display test patterns and browser information. Screen anomalies that persist at the same position need visual inspection and, when needed, professional assessment.
Open the patterns and guides for your device. True full screen and touch depend on the browser; an immersive page preview remains available when full screen is unsupported.
No installation is needed. Patterns, calculations and interactions run locally in your browser; theme preferences stay on your device.
Rule out dust, reflections and display settings. Repeat under the same conditions, photograph defects that remain in the same screen position and check the device warranty policy.