🎮 How to Play
- Click the red box to start.
- Wait for it to turn green - then click as fast as possible.
- Don't click while it's yellow / red - that resets.
- Average human: ~250ms. Top esports players: ~150ms.
About this tool
Average human reaction time is 250ms. Top esports players average ~150ms. The test measures simple visual reaction time - a stimulus appears, you click. Faster than 200ms is excellent.
About the reaction time test
Reaction time is the interval between a stimulus appearing and your motor response to it. This is a simple visual reaction time test: a coloured box turns green, and you click as fast as you can. It is the same green-light click test used in countless lab and sports-science studies, distilled to a single button. The tool runs five trials and reports the average, because a single click is too noisy to mean anything.
Simple reaction time reflects how quickly the visual signal travels from your retina to the brain, gets processed, and triggers a finger movement. Healthy adults average around 250 milliseconds. Elite gamers and athletes sit nearer 150 to 180 ms. The number is influenced by sleep, caffeine, age, and even your monitor, which is why averaging trials on consistent hardware matters.
How it works: what is being measured
The test records the time from the green cue to your click, then averages the trials. The measured time is the sum of several components, only one of which is your biology.
Measured time = display latency + your reaction + input latency Average of N trials = (t1 + t2 + ... + tN) / N Typical hidden hardware latency: 60 Hz monitor adds up to 16.7 ms (one refresh) 144 Hz monitor adds up to 6.9 ms wired mouse about 1 to 8 ms wireless/Bluetooth can add 10+ ms
Because hardware latency is baked into the reading, two people on different setups cannot be compared fairly. The honest comparison is your own average over time on the same screen and mouse.
Worked example
Say you run the five trials and get the following times in milliseconds.
- Trials: 245, 268, 231, 255, 241.
- Sum: 245 + 268 + 231 + 255 + 241 = 1,240.
- Average: 1,240 / 5 = 248 ms.
- Adjust for a 60 Hz screen: up to 16.7 ms of that is display latency, so your true reaction is nearer 231 ms.
Reaction time benchmarks
Approximate simple visual reaction time bands for healthy adults.
| Average time | Rating | Typical group |
|---|---|---|
| Over 300 ms | Below average | Tired, distracted, or older adults |
| 250 to 300 ms | Average | Most adults |
| 200 to 250 ms | Good | Alert, practised users |
| 150 to 200 ms | Excellent | Gamers, athletes |
| Under 150 ms | Elite | Professional esports players |
Common pitfalls
- Clicking too early. Anticipating the green cue and clicking during the red or yellow phase resets the trial. The test is measuring reaction, not prediction.
- Comparing across devices. A phone touchscreen, a 60 Hz laptop, and a 240 Hz gaming monitor produce different baselines. Only compare your own results on the same setup.
- Trusting a single trial. One fast click can be luck or a lucky guess. Always use the five-trial average for a meaningful number.
- Testing while tired or distracted. Fatigue and divided attention can add 30 to 60 ms. For a true baseline, test when rested and focused.
- Ignoring screen refresh rate. A 60 Hz display can silently add up to 16.7 ms that the test attributes to you, inflating your time.
- Expecting unlimited improvement. Training helps a little, but everyone has a physiological floor near 180 to 220 ms that practice cannot break through.
Frequently asked questions
What is a good reaction time in milliseconds?
Average adult simple visual reaction time is around 250 milliseconds. Under 250 ms is good, under 200 ms is excellent, and under 150 ms is at the level of professional esports players (CS, Valorant, fighting games). Reaction time peaks in the early twenties and drifts up by 10 to 15 ms per decade after age 30.
Why do my reaction times vary trial to trial?
Reaction time depends on focus, fatigue, caffeine, blood sugar, screen refresh rate, input device latency, and attention drift. A 30 to 50 ms spread across five trials is normal even when nothing else changes. To compare meaningfully, always average at least 5 trials and use the same monitor and mouse.
Does the monitor refresh rate matter?
Yes. A 60 Hz monitor refreshes every 16.7 ms; a 144 Hz monitor every 6.9 ms; a 240 Hz monitor every 4.2 ms. The screen cannot show the stimulus until the next refresh, so a 60 Hz display adds up to 16.7 ms of latency that the test attributes to you. For competitive comparisons use 144 Hz or higher.
Can I train my reaction time to be faster?
Yes, modestly. Daily 5-minute drills over 4 to 6 weeks lift simple reaction time by 5 to 15 percent on average. Gains plateau around your physiological floor (typically 180 to 220 ms for healthy adults). Caffeine improves reaction time by 5 to 10 ms; sleep deprivation slows it by 30 to 60 ms; sustained training compounds across both.
How does this differ from a choice-reaction or Stroop test?
This is a simple reaction time test: one stimulus, one response. Choice-reaction tests show multiple possible stimuli (left arrow, right arrow) and require you to pick the right key, adding 100 to 200 ms of decision time. The Stroop test layers color-word interference and measures executive function, not raw speed. Use simple RT for raw reflex, Stroop for attention control.