Reaction Time Test
Wait for the box to turn green, then click (or tap, or press Space) as fast as you can. You get five attempts and your average in milliseconds. Free, no sign-up.
How the reaction time test works
This is a simple reaction time test: one signal, one response.
- 1
Start
Click the box. It turns red.
- 2
Wait
A random 1.5 to 4.5 seconds, so you can't time it in advance.
- 3
Click on green
The timer starts the moment the box turns green and stops when your click, tap or key press arrives.
- 4
Five times
You see each time, your fastest and slowest, and the average.
What is a normal reaction time?
≈ 190 ms
to a light, in the lab
≈ 160 ms
to a sound, in the lab
250–350 ms
typical on browser tests
Reaction time has been measured for more than 150 years. Reviews of laboratory work put college-age adults at roughly 190 ms to a light and 160 ms to a sound, with equipment built to add almost no delay.
A web test always reads higher. A 60 Hz monitor draws a new frame only every 16.7 ms, the browser needs time to paint the green box, and mice, keyboards and especially touchscreens add their own lag. The same person can score 30–60 ms apart on two devices.
| Average on this test | What it usually means |
|---|---|
| Under 200 ms | Very fast, or a fast setup (wired mouse, high refresh-rate screen) |
| 200–250 ms | Quick |
| 250–350 ms | Common range for browser tests |
| Over 350 ms | Slower than typical: often a phone, fatigue or distraction |
What affects your reaction time
| Factor | Effect |
|---|---|
| Sleep | Lack of sleep reliably slows responses, makes them more variable and adds lapses. |
| Age | A survey of thousands of UK adults found reaction time slows gradually across adulthood, with bigger differences between people as they age. |
| Attention | Mind wandering, a buzzing phone or a long session all add milliseconds. |
| Warm-up | The first attempts of a session are usually the slowest. |
| Device | Refresh rate, input lag and browser load all count. |
Simple vs. choice reaction time
| Task | What the brain must do | Example |
|---|---|---|
| Simple | Detect one signal and fire one response | This test |
| Choice | Pick one of several responses: decision time grows with the number of options (Hick's law, 1952) | Pressing a different key for each color |
| Interference | Also hold back an automatic wrong answer | The Stroop test |
How to get a fair score
- 1
Get ready
Rest your finger on the mouse button, trackpad or Space bar.
- 2
Clear the decks
Close heavy tabs and turn off power-saving mode on laptops.
- 3
Warm up
Do one run, then record the next two or three averages.
- 4
Compare fairly
Only with your own earlier runs on the same device.
Can you train your reaction time?
Myth
Practising a reaction game makes you faster at everything.
What research says
You get faster at the task you practise. Evidence that the gain carries over to unrelated everyday skills is much weaker.
Sleep, regular activity and fewer distractions are the dependable basics. If you enjoy the challenge, Brainura's Reflex game sits next to 25 other short games for memory, attention, speed and logic, with difficulty that adapts as you improve.
Frequently asked questions
What is a good reaction time?
On a browser test like this one, an average under about 250 ms is quick, and many people land between 250 and 350 ms. Your device adds its own delay, so the number is most useful for comparing your own runs on the same screen and mouse.
What is the average human reaction time?
Laboratory studies with dedicated equipment usually put simple visual reaction time of young adults at around 190–250 ms, and reactions to a sound are typically somewhat faster than reactions to light. Browser tests read higher because of screen and input lag.
Why is my reaction time slower on my phone?
Touchscreens and phone displays add latency between the moment the screen changes and the moment your touch is registered. A wired mouse on a desktop with a high refresh-rate monitor usually gives the lowest numbers.
Does reaction time get slower with age?
On average, yes. Large population studies find that simple reaction time slows gradually through adulthood and more noticeably in later life, with wide differences between individuals.
Can I improve my reaction time?
Your score on a specific test usually improves with practice, sleep and a short warm-up. Whether practising one task makes you faster at unrelated everyday tasks is much less certain, so treat it as a fun skill to sharpen rather than a cure-all.
What happens if I click too early?
The attempt doesn't count and you get the same round again. The delay before green is random (1.5 to 4.5 seconds), so guessing the moment doesn't help.
Why do sprinters get a false start below 0.1 seconds?
Athletics rules treat a reaction to the starting gun of less than 0.100 s as a false start, on the reasoning that a genuine response to the sound can't be that fast; the athlete must have anticipated it.
Try next
Repeat digits forwards, backwards or a grid sequence. Find your memory span.
Reading Speed TestRead a short text, answer three questions, get your words per minute.
Schulte TableFind the numbers 1 to 25 in order. A classic attention and visual search drill.
Stroop TestName the ink color, not the word. Measure your own Stroop effect.
Train your reactions every day
Brainura has a reaction game, Reflex, plus 25 more short brain games for memory, attention and logic. Five minutes a day, no ads.
Free to install · no ads · no account needed
Sources
- Kosinski, R. J. (2013). A Literature Review on Reaction Time. Clemson University.
- Der, G., & Deary, I. J. (2006). Age and sex differences in reaction time in adulthood: results from the United Kingdom Health and Lifestyle Survey. Psychology and Aging, 21(1), 62–73.
- Hick, W. E. (1952). On the rate of gain of information. Quarterly Journal of Experimental Psychology, 4(1), 11–26.
- Lim, J., & Dinges, D. F. (2008). Sleep deprivation and vigilant attention. Annals of the New York Academy of Sciences, 1129, 305–322.
- Simons, D. J., et al. (2016). Do “brain-training” programs work? Psychological Science in the Public Interest, 17(3), 103–186.