Reaction time, and what a good score is

What this tool does

The Reaction Time Test shows a box that turns from red to green after a random delay. The moment it turns green, you click — and it reports how many milliseconds elapsed, along with your average of the last five tries and your best. It all runs in your browser.

How it's measured

When the box turns green the tool records a high-resolution timestamp; when you click, it records another and reports the difference in milliseconds. The delay before green is randomised between roughly 1.2 and 4 seconds so you can't anticipate it — click too early and it tells you to try again.

What is a good reaction time?

• Under 200 ms — very fast, the range of trained gamers and athletes.
• 200–250 ms — fast, sharper than average.
• 250–300 ms — typical for a visual cue.
• 300 ms+ — on the slower side, or just a distracted attempt.

What affects your score

Attention, fatigue, caffeine, and even your mouse and monitor's input lag all move the number. Because a single try is noisy, the average of several attempts is the figure worth watching — and your reflexes naturally vary from moment to moment.

How to use it

1. Open the Reaction Time Test.
2. Click the box to arm it, then wait — don't click while it's red.
3. The instant it turns green, click as fast as you can.
4. Read your time; click again to take another attempt and build an average.

Your score stays private

Everything runs locally in your browser — your results stay in the current tab and are never uploaded.

FAQ

What is a good reaction time?

Most people score 200–300 ms; around 200 ms is fast, and competitors often reach 150–200 ms.

Why does my reaction time vary so much?

Attention, fatigue, caffeine and input lag all affect it — that's why the average matters more than one try.

Is my score uploaded?

No — it all runs in your browser.

Ready to try it? Open the Reaction Time Test →