Output
Event-to-animation callback time, milliseconds
UserBenchmark / All Tools / Mouse Event Latency Test
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Mouse Event Latency Test
Measure browser event-to-next-frame delay for mouse clicks.
Free to useNo downloadNo sign-up
Mouse Event Latency Test · At a glance
Quick answer: Measure browser event-to-next-frame delay for mouse clicks. The clock begins in the event handler and ends at the next animation callback.
Mouse Event Latency Test
The test loads when you open it. Device access is requested only after you choose to start.
Detailed guide
How to use this tool
- Click the surface repeatedly and inspect the median event-to-next-frame interval.
- Compare runs only with the same display and browser settings.
Input
Clicks or focused key presses
Browser requirement
requestAnimationFrame; performance timestamps
Processing
Runs on your device; no tool-result upload
How it works and what the result means
The number measures time from handling the browser input event to the next animation frame callback. It does not measure USB hardware latency, switch actuation or actual photon response.
Reading the result
The clock begins in the event handler and ends at the next animation callback. It excludes the earlier hardware and operating-system path.
This number is not total mouse latency
The clock starts inside the input handler and stops at the next animation callback. A sub-millisecond result is possible when input arrives just before a scheduled frame. It does not include the complete mouse, OS, rendering and panel pipeline. Use a camera or dedicated instrument to measure physical end-to-end latency.
What to check next
Keep the tab visible and close heavy workloads. A click arriving just before a frame can produce a very small number.
Frame scheduling, tab visibility and system load affect the result. Compare the median under the same conditions and avoid treating this number as end-to-end input lag.
Frequently asked questions
Does a sub-millisecond result mean total mouse lag is below 1 ms?
No. The interval covers only part of browser scheduling. Physical switch-to-photon latency needs an external measurement method.
How do I start the Mouse Event Latency Test?
Click the test surface or press a key, depending on the selected test. Repeat for several samples.
Does this tool require a download or an account?
No. Open the interactive tool above in a modern browser. The instructions and explanations are available even with JavaScript disabled; running a test needs JavaScript.
Why can two attempts give different results?
Power settings, background tasks, browser scheduling, operating-system input processing and device settings affect measurements. Compare repeated attempts with identical settings rather than the single highest score.