What is a good reaction time?

There is no single number that fits everyone. Your result depends on your device, your screen and how you click or tap, so the fairest comparison is with your own earlier tries on the same device.

Why is my result different on a phone and a computer?

Every device adds its own small delay: the touch screen or mouse needs time to register the press, and the screen needs time to show the green color. Phones and computers handle this differently, so their numbers are not directly comparable.

Should I use the spacebar, the mouse or the screen?

Use whatever is most comfortable and stick with it. Each way of pressing adds its own small delay, so switching between them makes your results harder to compare.

How accurate is this test?

It measures the time in your browser between the moment the box turns green and the moment your press is registered. That is accurate enough to compare your own tries, but it always includes some delay from your hardware, so treat the numbers as approximate.

Are my results saved?

No. The test runs entirely in your browser. Your times are not sent to us and are gone when you leave the page.

Can I use this test with a screen reader?

Not really, sorry. The test is about seeing the color change, and a screen reader can’t announce it at a precise moment. The other parts of this page work with screen readers.

Can this test tell me something about my health?

No. It is a quick game for curiosity and fun, not a medical test. If you are worried about your reactions, your memory or your health in general, talk to a doctor.

Reaction Time Test

Test your reaction time in about a minute. Wait for the screen to turn green, then click, tap or press the spacebar as fast as you can.

Reaction Test

Wait for green, then click, tap or press the spacebar as fast as you can.

5 tries · about a minute

Keyboard: Space or Enter

Nothing flashes or moves: the box switches from dark to green once and stays green until you press.

Your result

Typical time –ms

Fastest try– ms

“Too soon” clicks–

All tries

“Typical time” is the median of your five tries. Times include the delay of your screen, mouse or touch screen, so compare only with your own results on the same device.

Next: Stroop Test

How the test works

Press Start. The box turns dark and says “Wait for green”.
After a random pause of a few seconds, the box turns green and says “Click!”.
React as fast as you can. Your time for that try appears right away.
Click again for the next try. After five tries you see your typical time and your fastest try.

The pause before green is different every time, so you can’t learn the rhythm and click in advance. If you click while the box is still dark, you see “Too soon” and that try simply starts over. It doesn’t count against you, but the number of early clicks is shown at the end.

Reaction time test with mouse, touch or spacebar

You can take the test in three ways. On a computer, click the box with your mouse or press the spacebar. On a phone or tablet, tap the box with your finger. The test registers the moment your finger or mouse button goes down, not when you let go, so you don’t lose time lifting your finger.

Pick one way and keep it for every try. A mouse, a keyboard and a touch screen each add their own small delay, and mixing them makes your numbers jump around for reasons that have nothing to do with you.

Test your reaction time: how to read the result

After five tries you see four things:

Typical time is the median of your five tries: the middle value when they are sorted. One unusually slow or lucky try doesn’t change it much.
Fastest try is your single best time in this round.
All tries lists every time, so you can see how steady you were.
“Too soon” clicks shows how often you jumped the gun.

There is no pass mark and no ranking against other people here. The useful question is how your own numbers change: from try to try, at different times of day, or when you are rested compared with when you are tired.

Why your time changes between tries and devices

Reaction time is never the same twice. Attention drifts, you blink at the wrong moment, or you are still settling into the rhythm. That is why the test uses five tries and shows the median rather than a single number.

Your device matters too. A screen needs a moment to draw the green color, and a mouse, keyboard or touch screen needs a moment to report your press. Some browsers also round their clocks slightly for privacy. All of this is included in the time you see, which is why a result on your phone and a result on your laptop are not directly comparable.

Everyday things play a part as well: how much you slept, whether you just had coffee, how comfortable you are sitting. None of this is something to worry about. It is simply worth knowing before you compare two results.

What is reaction time?

Reaction time is the time between something happening and your response to it. In this test there is one signal and one possible response, which is the simplest kind, sometimes called simple reaction time.

When you have to choose between several responses, things take longer, because your brain has to decide as well as react. The Stroop test is a good example: you see a word and a color and have to pick the right answer while ignoring the wrong one. If you enjoy this test, it is a nice next step.

Tips for a fair attempt

Sit comfortably and keep your finger or cursor resting on the box, so you don’t lose time reaching for it.
Close other busy tabs and apps that might slow your device down.
Look at the box, not at the keyboard or your hand.
Don’t try to guess when green will come. Guessing leads to “Too soon” clicks and doesn’t make you faster.
If you want to compare results over time, use the same device, the same way of clicking and a similar time of day.

Looking for more short brain games?

Brain Games for iPhone doesn’t have a reaction game. It has five other short games for attention, memory and mental math: Stroop, Odd One Out, Mental Math, Visual Memory and Word Memory.

The app is free to download. Playing the games requires a subscription, and the price is shown in the app before you subscribe.

View on the App Store

Questions

What is a good reaction time?: There is no single number that fits everyone. Your result depends on your device, your screen and how you click or tap, so the fairest comparison is with your own earlier tries on the same device.
Why is my result different on a phone and a computer?: Every device adds its own small delay: the touch screen or mouse needs time to register the press, and the screen needs time to show the green color. Phones and computers handle this differently, so their numbers are not directly comparable.
Should I use the spacebar, the mouse or the screen?: Use whatever is most comfortable and stick with it. Each way of pressing adds its own small delay, so switching between them makes your results harder to compare.
How accurate is this test?: It measures the time in your browser between the moment the box turns green and the moment your press is registered. That is accurate enough to compare your own tries, but it always includes some delay from your hardware, so treat the numbers as approximate.
Does the screen flash?: No. Nothing flashes, blinks or moves. In each try the box switches from dark to green once and stays green until you press. After that it shows your time.
Are my results saved?: No. The test runs entirely in your browser. Your times are not sent to us and are gone when you leave the page.
Can I use this test with a screen reader?: Not really, sorry. The test is about seeing the color change, and a screen reader can’t announce it at a precise moment. The other parts of this page work with screen readers.
Can this test tell me something about my health?: No. It is a quick game for curiosity and fun, not a medical test. If you are worried about your reactions, your memory or your health in general, talk to a doctor.