Reaction Time Test
Click as soon as the box turns green. Do 5 rounds to get your average.
How the test measures your reaction
The box turns green after a random wait of one to four seconds, and the timer starts on the exact frame that colour is painted to your screen. Your score is the gap between that frame and your click, so it bundles three separate steps: the eye passing the signal to the brain, the brain deciding it is the green you were waiting for, and the hand sending the press to the mouse button.
The wait is randomised on purpose. With a fixed delay you would quickly learn the rhythm and click just before the change, which measures your sense of timing rather than your reaction. Clicking while the box is still red voids the round for the same reason.
Five rounds are averaged because a single attempt is noisy. One blink, one glance away or one lucky guess can shift a trial by more than a tenth of a second, and averaging smooths that out.
What your average means
- Under 200 ms — faster than most people. Common among regular action-game players, and hard to reach on a slow display.
- 200-250 ms — the range most healthy adults land in on a mouse.
- 250-350 ms — normal on a touchscreen, or on a first attempt before you settle in.
- Over 400 ms — usually tiredness, divided attention or a delay in the hardware rather than anything about you.
Things that change the number
Your equipment is part of the measurement whether you like it or not. A 60 Hz screen only repaints every 16.7 ms, so it adds about 8 ms on average before you even see the green; a 144 Hz screen cuts that to roughly 3 ms. Wireless mice, cheap touchscreens and browser tabs busy in the background each add a few milliseconds more.
Reaction time is also slowest right after waking, dips through the afternoon and lengthens steadily with age from the twenties onward. Comparing your own score across the same setup and time of day tells you far more than comparing it with a stranger's.
- Rest your finger on the button instead of hovering above it — the travel distance is real time.
- Look at the centre of the box, not the edge. Central vision detects the change sooner.
- Do not try to predict. Anticipation produces one great round and several voided ones.
- Take the test twice and keep the second result — the first run is usually spent learning the layout.
Frequently asked questions
What is a good reaction time?
The average human visual reaction time is about 200–250 ms. Under 200 ms is considered fast, and competitive gamers and athletes often reach around 150 ms.
Why is my reaction time slow?
Fatigue, lack of sleep, age, screen or mouse/touch lag, and distractions all slow you down. Resting, a low-latency display and repeated practice usually help.
How is reaction time measured here?
We measure the time between the box turning green and your click, in milliseconds, and average it over 5 rounds. Clicking before green counts as too soon.
Does age affect reaction time?
Yes — simple reaction time is fastest around your early-to-mid twenties and slows gradually afterwards. Regular exercise, good sleep and practice on the specific task can offset a large part of the age difference.
How can I make my reaction time faster?
Sleep well, stay physically active, and practice the exact task — repeated attempts on the same test reliably shave off milliseconds. Caffeine gives a small temporary boost. Huge jumps are unrealistic, but going from 280 ms to 220 ms with practice is common.
Why is my reaction time worse on my phone?
Touchscreens add input latency, and a 60 Hz display refreshes about every 17 ms, so the green signal itself appears later than on a fast gaming monitor. Compare scores only against attempts on the same device.
Do professional esports players really react faster?
On average, yes — top esports and fighting-game players often test in the 150–180 ms range, compared with roughly 200–270 ms for most adults. But their real edge is anticipation: reading the game so well that they start moving before the stimulus even appears.
Do sleep and caffeine affect reaction time?
Strongly. Sleep deprivation slows reactions measurably — pulling an all-nighter can impair you about as much as being over the drink-drive limit. A moderate dose of caffeine speeds simple reaction time slightly for a few hours. If your score suddenly drops, tiredness is the first suspect.