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Reaction time test
Wait for green, then click, tap or press space as fast as you can. Five attempts, and your median reaction time in milliseconds at the end.
This test runs in your browser with JavaScript. Turn it on to play, or get Omni Brain for the full version.
How to play
- Press Start. The box stays grey for a random 1.5 to 4 seconds.
- When it turns green, click, tap or press space as fast as you can. Pressing early shows Too soon and restarts that attempt.
- After five good attempts you see your median time and every attempt in milliseconds.
What your score means
Your score is the median of your five attempts: the middle time once they are sorted, so one slow or lucky try does not decide the result. Lower is faster.
Simple visual reaction times of adults are typically around a quarter of a second on a good screen. Every device adds its own delay on top: the display, the mouse, keyboard or touch screen, and the browser each take a few milliseconds or more. Compare results on the same device, and expect a phone and a desktop to give different numbers.
About reaction time tests
A reaction time test measures how quickly you respond to a signal you are waiting for. It is one of the oldest measurements in psychology. In the 1860s the Dutch physiologist Franciscus Donders compared simple reactions, one signal and one response, with choice reactions, where you first have to tell signals apart, and used the difference to estimate how long a mental step takes. This test is a simple reaction task. It draws on alertness, how fast you notice the change and a quick, prepared movement, and it also asks for patience: the pause is random, so guessing leads to early presses. Practice trims your time a little and, above all, teaches you not to jump the gun. In Omni Brain the same idea runs as the Reaction game, which adds choice reactions and adapts its difficulty to you as you play.
Techniques from the app
- Finger ready, mind quiet. Rest your finger just above the screen and stop predicting. Reaction is fastest when you are not guessing.
- Breathe out. A long exhale before the signal steadies the hand and cuts false starts.
Train your reaction speed every day in Omni Brain
Reaction and many more short games, each with a technique you can use outside the app. Free every day.
Questions about reaction time
What is a good reaction time?
Simple visual reaction times of adults are typically around a quarter of a second on a good screen. An online test also includes the delay of your display and input, so the fairest comparison is your own earlier result on the same device.
Why is my time slower on a phone?
Touch screens and phone displays can add more delay than a wired mouse and a fast monitor, and holding the phone changes how ready your finger is. Use the same device each time to follow your progress.
Why is the wait before green random?
So you cannot predict it. With a fixed pause you would learn the rhythm and press in time with it, which measures timing rather than reaction. A random wait of 1.5 to 4 seconds keeps the test fair.
Can I improve my reaction time?
A little, yes. Practice, good sleep and a ready, relaxed hand all help, and learning not to guess cuts false starts. The app's technique is simple: finger ready, mind quiet.