How to take the test
- Tap the blue box — it turns red. That means “get ready”.
- After a random pause of 1.5 to 4 seconds the box turns green. Tap as soon as you see green.
- Tapping while it is still red counts as a false start, and you repeat the try.
- Complete 5 tries: an average is more reliable than one lucky or unlucky attempt.
What counts as a good reaction time
In the lab, simple reaction time to light in young adults is usually around 200–250 ms. In a browser or on a phone the numbers are higher: the latency of the screen, mouse or touch sensor is added to your reaction, from a few to several dozen milliseconds. So the table below is a guide for online tests, not a medical norm.
| Result | Rating |
|---|---|
| under 200 ms | Very fast — the level of well-trained gamers and athletes |
| 200–250 ms | Faster than average |
| 250–300 ms | A typical adult result in an online test |
| 300–350 ms | A little slower than average — check whether you are tired |
| over 350 ms | Slow for a simple reaction: often fatigue, distraction or device lag |
What affects your result
- Sleep and fatigue. Sleep loss noticeably slows reactions and increases lapses.
- Age. Simple reaction time slows gradually with age, though regular activity slows the decline.
- Attention. Drifting off for even a split second adds dozens of milliseconds.
- Your device. Refresh rate, a wireless mouse and the touch sensor add latency. Compare yourself on the same device.
- Alcohol and some medications impair reactions — one of the reasons you must not drive after drinking.
How to improve your reaction time
Simple reaction time improves quickly in the first days of training while you get used to the task, then it plateaus. To keep improving, vary the signals and add choice tasks. The Cabe app has more than 20 games for that: reacting to sound and vibration, the Formula F1 start, Reverse, peripheral vision and dodging. Every attempt is saved in your statistics, so you can see how your average changes.
For a detailed breakdown with norms and exercises, read our guide How to improve your reaction time.