Why the median and not the average
One distracted round at 600 ms wrecks an average. It barely moves a median. Five rounds is enough to throw away the outliers and still finish in under a minute, which is about how long anyone's patience lasts for this.
A false start (hitting while the box is still red) doesn't count as a round; you repeat it. The number of false starts is shown with the result because it says something too: lots of them means you were guessing the timing, not reacting.
What the milliseconds mean
| Median | Level | Notes |
|---|---|---|
| under 180 | Elite | Rare on a normal monitor and mouse |
| 180 to 220 | Fast | Gamers with a high refresh screen |
| 220 to 260 | Average | Where most people land |
| 260 to 320 | Relaxed | Tired, distracted, or a slow setup |
| 320+ | Sleepy | Try again after a walk |
Anything under about 120 ms is not a reaction. The signal has to travel eye to brain to finger, and that alone takes longer. A score down there means you anticipated the green or a device is clicking for you.
Your hardware is in the number
The test measures from the moment the browser paints green to the moment the click event arrives. Both ends add delay you can't control. A 60 Hz monitor shows a new frame every 16.7 ms, so on average you see the green 8 ms late; at 240 Hz that drops to 2 ms. A wireless mouse in power-saving mode can add 10 to 20 ms; a 125 Hz USB mouse up to 8. Add the operating system's own input queue and the same person will score 20 to 40 ms better on a gaming PC than on a school laptop. Compare your scores across days on the same machine, not against someone else's setup.