Reaction Time Test measures how fast you respond to a visual cue. Click to start, wait for the box to turn green, then click, press the spacebar, or tap on mobile as quickly as you can. High-precision browser timing records the result in milliseconds.
After a run you get a grade and a percentile, plus your best score, average, median, and recent history — all kept in the browser, with no sign-up. You can choose 1, 3, 5, or 10 rounds; more rounds give a more reliable average, since a single attempt is mostly noise.
Key Features
- Millisecond precision — High-precision browser timing.
- Grade and percentile — Not just a number, but where it sits.
- Selectable rounds — 1, 3, 5, or 10 per run.
- Local history — Best score, average, median, and recent attempts stored in your browser.
- Mouse, keyboard, or touch — Click, spacebar, or tap on mobile.
- No sign-up — Free, runs entirely in the browser.
What Counts as Fast
The site cites average human reaction time at roughly 250 milliseconds, with most people falling between 200 and 300 ms. Anything under 200 ms is excellent; 200–250 ms is fast, and 250–300 ms is typical.
Worth knowing when you compare scores: attention, fatigue, monitor refresh rate, mouse polling rate, and browser performance all shift the result, so cross-device comparisons are rough at best.
How It Works
- Click to start.
- Wait for the box to turn green.
- Click, press space, or tap as fast as you can.
- Run several rounds for a reliable average.
The site is explicit about its limits: “This is a fun self-test for measuring and improving your reaction speed. It is not a medical, diagnostic, or scientific assessment.”