Reaction Time Test
Wait for the panel to turn green, then click as fast as you can. 5 trials, and you get the median — free, instant, no account.
How this test works
This is the simple reaction time paradigm: one stimulus, one response, no choice to make. The panel waits a random 1.5–4.5 seconds so the change can't be anticipated by rhythm, then turns green. The clock starts at that moment and stops on your click.
Clicking before green voids the trial rather than scoring it, and a response under 100 ms is treated the same way — simple reaction time doesn't go that low, so a press that fast was already in flight before the colour changed. You get the median of 5 valid trials, not the mean, so one mistimed click doesn't drag the headline number.
What the number means
The best-calibrated large study puts mean simple visual reaction time for adults at about 231milliseconds — roughly 200–220 ms once hardware and display delays are subtracted. Your browser result will sit above that, and the gap is mostly equipment, not you. That is also why we report a reading against published research instead of a percentile against numbers we can't verify.
Reaction time: what's normal? — the research, with sources →Train it, don't just measure it
A single number tells you where you are today. Moving it takes practice against a real skill ceiling — and raw speed is only half of it, since a fast click on the wrong target scores nothing. Quantum Grid works the speed–accuracy tradeoff on decaying targets, and Cardinal Pulse moves the same demand to your ears, where reaction is measurably faster than to sight.
Reaction time FAQ
+What is a good reaction time?
On calibrated laboratory hardware, mean simple visual reaction time for adults is about 231 milliseconds — roughly 200–220 ms once display and input delays are subtracted. A browser test measures higher than that for the same person, because your monitor, mouse and browser each add their own latency.
+Why is my score different on other websites?
Because none of them measure the same thing. Display refresh rate, input device polling, browser and background load all add tens of milliseconds, and no browser test can subtract them. Comparing your number between sites is meaningless; comparing it to your own past runs on the same device is not.
+Does reaction time get slower with age?
In a UK study of over 7,000 adults aged 18–82, simple reaction time held roughly steady until about age 50 before slowing. Four-choice reaction time — where you also have to decide — slowed steadily across the whole adult range. The decision stage ages faster than the raw signal-to-muscle pathway.
+Can you train reaction time?
Research on action gaming finds trained players respond faster without losing accuracy, so the speed–accuracy tradeoff itself is trainable. What no test can promise is that a faster click transfers to unrelated parts of your life — read the honest summary before believing bigger claims.
+Is this test free?
Yes, and no account is needed. Nothing is stored or submitted — the measurement happens entirely in your browser.