GEARCHECK LABMeasure the combined time between a browser-rendered visual cue and your click, tap or keyboard response. Complete five unpredictable trials and compare the median while keeping the same device and input method.
Left click, tap, Space or Enter. Wait for both the GO label and green colour. Early presses are excluded.
Each result is the browser time from updating the GO cue in an animation callback to receiving your response event. The median is the middle result of five sorted valid trials; it is less influenced by one unusually slow response than the arithmetic average. The best result is the smallest completed value, not your typical performance. False starts are counted separately and never treated as fast valid responses. The tool provides measurements rather than a universal pass, warning or fail threshold for people or devices.
This is not a medical assessment, an esports ranking, or a measurement of mouse input lag alone. Your visual processing, attention, display scanout, browser scheduling, operating system and input device all contribute. A rendering callback does not identify the exact instant the physical screen changed. Comparing a touchscreen run to a keyboard run mixes multiple variables. Backgrounding or unfocusing the page cancels the unfinished trial; already completed trials remain visible. Repeat with a comfortable posture and consistent input method instead of drawing conclusions from one number.
No. It includes your reaction and the entire screen-to-browser input path. A mouse latency measurement requires a different controlled setup.
Pressing during WAIT is a false start. The trial is excluded and you can retry with a fresh randomized delay.
Diagnostic input and results are processed locally in this browser tab. This tool does not upload the sample or ask you to create an account. Reset or reload clears the current sample. Normal website requests and any analytics you choose to allow are described in our privacy policy.