Is this a measure of intelligence?

No. Reaction time is a speed benchmark. It correlates with some cognitive constructs but is not an IQ test.

Why are my phone and desktop results different?

Touch and display input pipelines add different amounts of latency. We store device and input class so norms stay fair.

What counts as a false start?

Responding before the green signal appears. False starts are flagged and don't count toward your median.

Reaction Time

How fast do you respond to a visual signal?

~2 min

Measured values depend on your device, input method, display refresh rate, operating system and environment. This is not laboratory-grade measurement.

What this measures

Reaction Time measures the time between a visual signal appearing and your response. It is a direct benchmark of your sensorimotor speed, not a psychological trait.

How it works

Wait for the panel to turn green, then respond as quickly as you can. You get 3 practice trials and 15 scored trials with randomized foreperiods to prevent anticipation.

How results are calculated

Your result is the median of 15 valid trials in milliseconds. Faster is better. False starts and tab-blur events are flagged and excluded from the median. Device and input latency affect results, so phone and desktop are not directly comparable.

Accuracy & limitations

Hardware latency, monitor refresh rate and browser backgrounding can all shift results. This is a utility benchmark (Evidence C), not a clinical measure.

FAQ

Science & Research

All science

Reaction Time and Cognitive Performance

Reaction time — the milliseconds between a stimulus and your response — is one of the oldest and most reliable measures of cognitive processing speed. Over a century of research has linked it to intelligence, aging, sleep, and even longevity.

Read article

Keep exploring

Visual Reaction~2 min Audio Reaction~2 min Visual Memory~7 min Full IQ Estimate~30 min

Last reviewed: 2026-08-14