Free Attention Span Test (Reaction-Time Check)
Read this before you start
This is a reaction-time task, not an attention-span measurement and not a diagnosis. It tells you how alert you are right now compared to your own previous runs. Reaction time is one narrow slice of attention, and a single run says very little. It is useful as a personal trend, nothing more.
Tap, or press Space or Enter, the instant the circle below changes, 45 times in a row. It takes about 3 minutes. Nothing you tap and no result is ever saved or sent anywhere: it appears on this screen and nowhere else, and it disappears the moment you leave or refresh the page.
Tap, or press Space or Enter, the instant it changes.
Your result, this run only
0 ms
Lower reaction time means you reacted faster. “Lapses” are taps slower than about a third of a second, moments your attention slipped. “Consistency” is how steady your times were; lower is steadier. One run is noisy: the trend across many runs over weeks is what actually means something, exactly like the in-app version of this check.
Want to actually train this, not just check it?
Dopa Break turns this same reaction-time check into a repeatable habit, alongside progressive focus training. Dopa Break is free to use on the web, with no card required and no ads in the app.
Try Dopa Break freeWhat is this actually measuring?
Reaction time to a simple visual cue, nothing more. It is modelled on the psychomotor vigilance task, the reaction-time vigilance test sleep and attention researchers actually use, run here as 45 trials over a random 1 to 4 second wait, which takes about 3 minutes. A tap under 100 milliseconds is treated as a guess rather than a real reaction and does not count toward your result. A reaction slower than 355 milliseconds is counted as a “lapse”, a moment your attention visibly slipped.
Why isn't there a score out of 100, or a percentile?
Because we do not have population data to compare you against, and inventing a benchmark would be worse than showing none at all. This page will never claim to know what a typical result looks like, and it will never show a made-up percentile. Your result is only ever compared to your own previous runs, never to anyone else.
Is this the same check as the one inside the Dopa Break app?
Yes, the same parameters: 45 trials, roughly 3 minutes, the same 355 millisecond lapse threshold and the same under-100-millisecond false-start rule. The app version additionally saves each run so you can see your trend over weeks; this free page keeps nothing, by design, so you can try it with no account at all.
Does anything I do here get saved or sent anywhere?
No. The countdown, your taps and your result all run in plain JavaScript in your own browser. This page makes no network request of any kind while you use it, sets no cookie, and calls no analytics or tracking script. Refresh the page and your result is gone, on purpose.