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Ubify Core Engineering Team
SOFTWARE ENGINEERS & SYSTEMS ARCHITECTS
About This Tool
Measure your visual reaction latency and reflex speed in milliseconds. When prompted, wait for the red screen to turn green, then click or tap as quickly as possible. The tool utilizes randomized delay intervals (between 1.5 and 4.5 seconds) to prevent anticipatory false starts, measuring true neuromuscular response time with high-resolution timestamps.
How to Use
- 1
Click the testing surface to initiate the reflex benchmark sequence.
- 2
Wait attentively while the screen remains red during the randomized delay window.
- 3
Click or tap immediately the instant the screen color changes to green.
- 4
Review your measured reaction latency in milliseconds.
Frequently Asked Questions
How does this test measure reaction time accurately?
The moment the screen background shifts to green, JavaScript records a start timestamp. When your mouse click or touch event registers, elapsed time = click timestamp - start timestamp in milliseconds.
What is an average healthy human visual reaction time?
Typical human visual reaction times average between 200 and 250 milliseconds. Reaction times below 180 ms indicate exceptional athletic or gaming reflexes, while times above 300 ms often reflect fatigue or distractions.
What happens if I click before the screen turns green?
Clicking during the red preparatory phase triggers a false start warning and cancels the trial, ensuring recorded reflex metrics reflect genuine stimuli reactions rather than lucky guessing.
Are reaction test scores or timing logs uploaded to external servers?
No. All event listeners and millisecond timing calculations operate entirely client-side in your local browser sandbox.