Measure your reaction speed in milliseconds. Wait for the green signal and click as fast as you can — averaged over 5 attempts.
You'll do 5 rounds. Wait for the box to turn green, then click as fast as possible. We'll show your average reaction time. Don't click too early!
A reaction time test measures how quickly you can respond to a visual stimulus. It's one of the simplest yet most revealing measures of cognitive processing speed — the time it takes for your brain to perceive a signal, process it, and trigger a physical response.
Reaction time is typically measured in milliseconds (ms). The average human visual reaction time is around 200–300 milliseconds. Elite athletes, gamers, and pilots often have faster reaction times due to extensive training, while fatigue, age, and distraction can slow it down.
Our reaction test uses a simple but effective method. A box appears and stays in a "wait" state for a random amount of time. The moment it turns green, you click as fast as possible. The timer measures the exact gap between the color change and your click. We repeat this 5 times and calculate your average, which gives a more reliable result than a single attempt.
Clicking before the box turns green counts as a false start — so stay alert but don't anticipate too aggressively. This mirrors how reaction time is measured in sports science and cognitive research labs.
Many factors influence your reaction speed: sleep deprivation can slow it dramatically, while caffeine and physical alertness can sharpen it. Age plays a role too — reaction time tends to peak in the early twenties and gradually slows afterward. Your device and screen also matter; a laggy screen or slow mouse can add 20–50ms to your measured time.
The good news is that reaction time can be improved with practice. Action video games, sports, and reaction-training exercises have all been shown to enhance response speed over time.
This page focuses only on reaction speed. To measure your complete cognitive profile — memory, focus, pattern recognition, and processing speed combined into one brain age — take our full Brain Age Test.
Take the complete 2-minute cognitive challenge.
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