Reaction time test · three attempts · milliseconds
Reaction Test
How fast do you answer a green light? Wait for the panel to turn green, then tap, click or press space. Three attempts give you a best and an average reaction time in milliseconds, plotted against the typical human range — then export or share the result.
This round on the scale
Nothing measured yet- Last attempt
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- Best this round
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- Round average
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Your saved records
Records are held in this browser only. Export them before clearing your browser data.
How to play
The test takes about a minute. One rule matters: react to the light, never predict it.
- Start the roundTap the blue panel, click it, or press the space bar. The timer arms and the countdown to the green signal begins.
- Wait for greenThe panel holds for a random 1.2 to 3.5 seconds. Keep your finger still. Tapping early voids that attempt and restarts it, so guessing never pays.
- React the instant it turns greenTap, click or hit space as fast as you can. Your time in milliseconds appears immediately on the panel and on the scale below it.
- Repeat for three attemptsA round is three valid attempts. The lamps on the panel show how many you have completed, and the round ends with your best and your average.
- Save, export or shareFinished rounds are stored in your browser. Export them as CSV or JSON any time, or share your average as a score card.
What your reaction time means
Use this as a rough guide for a mouse or trackpad on a desktop screen. Touchscreens usually add 20 to 60 milliseconds, so judge a phone score against other phone scores.
| Average | Band | What it usually means |
|---|---|---|
| Under 180 ms | Exceptional | Elite territory, and worth checking you were not anticipating the light |
| 180–220 ms | Fast | Well above average; common among trained gamers on low-latency gear |
| 220–280 ms | Typical | Where most alert adults land on a desktop |
| 280–350 ms | Relaxed | Normal on a phone, when tired, or without a warm-up round |
| Over 350 ms | Slow for you | Usually distraction, fatigue or a laggy device rather than reflexes |
Frequently asked questions
The questions we get most about reaction time and how this test measures it.
What is a good reaction time?
Anything under 250 milliseconds is solid, and under 200 ms puts you in the fastest few percent of people using a mouse. The median result on a click-based test like this one sits around 250 ms. Times above 350 ms usually mean tiredness, a slow input device or a touchscreen rather than anything about you.
What is the average human reaction time?
Simple visual reaction time for healthy adults falls between 200 and 300 milliseconds, with most laboratory studies putting the mean near 250 ms. Reacting to sound is slightly faster at roughly 170 ms, and touch is faster still, because light takes longer to process than a bang or a tap.
Why is my reaction time slower on a phone?
Touchscreens sample your finger at a fixed rate and add processing before the browser sees the tap, which typically costs 20 to 60 milliseconds against a wired mouse. Your score is real, it just includes more hardware delay. Compare phone rounds with phone rounds.
Does monitor refresh rate change my score?
Yes. On a 60 Hz screen the green signal can sit unpainted for up to 16 ms before you can possibly see it; on a 144 Hz screen that drops to about 7 ms. That difference alone can account for 10 ms between two people with identical reflexes.
Why do I keep tapping too early?
Because you are predicting the delay instead of responding to the light. The wait is randomised between 1.2 and 3.5 seconds precisely to break that habit. Early taps void the attempt rather than scoring, so guessing costs you time instead of saving it. Relax your hand and watch the panel, not the clock.
How can I improve my reaction time?
Sleep is the single biggest factor, followed by warming up with a few practice rounds, sitting properly, resting your finger lightly on the button and looking at the centre of the panel rather than its edge. Moderate caffeine helps a little. Genuine long-term gains come from regular practice, but expect tens of milliseconds, not hundreds.
Why only three attempts?
One attempt is noise: a single lucky tap tells you nothing. Three gives you a best and a meaningful average while the round is still short enough that fatigue and boredom do not creep in and drag your numbers down.
Is my score saved or sent anywhere?
No. Every round is written to storage inside your own browser and never reaches a server. Nobody else can see your history, and clearing your browser data or pressing Clear all removes it for good.
Can I export my results?
Yes. The records table exports to CSV for spreadsheets or JSON for anything else, with every attempt, your best, your average and a timestamp for each round.
What is the fastest reaction time possible?
Around 100 to 120 milliseconds is the accepted floor for a genuine visual response, which is why sprinters who leave the blocks faster than 100 ms after the gun are ruled to have false-started. Scores below that on this test mean the tap was anticipated, not reacted.
Does age affect reaction time?
Reaction time improves through childhood, peaks somewhere in the twenties and slows gradually after that, with the decline becoming clearer past 60. The effect is real but modest compared with how much sleep, alertness and your equipment matter on any given day.