Reaction Time Test
How fast are your reflexes? Wait for green, then tap as fast as you can. We measure your reaction in milliseconds across 5 rounds — and compare it to F1 drivers, your own blink, and the speed of your nerves.
Round 0 of 5 complete.
The science of reaction time
Eyes → brain → muscle
When the screen turns green, light hits your retina, the signal travels to your visual cortex, your brain decides to act, and a command races down your spinal cord to the muscles in your hand. Each step costs time, which is why even a perfect reaction takes a couple of hundred milliseconds.
What's a normal reaction time?
For a simple visual reaction, healthy adults average around 250 ms (roughly 200–280 ms). Athletes and gamers tend to be at the fast end, and reaction time slows with fatigue, alcohol and age.
Sound beats sight
We react to sound faster than to light: auditory reactions average about 150 ms versus about 250 ms for vision. That's why sprinters start to a gun, not a flash — the sound reaches the brain through a shorter pathway.
How fast do nerves fire?
Signals travel along your fastest motor nerves at up to about 120 m/s — but most of your reaction time is spent on processing in the brain, not on conduction along the nerve.
SourceHow you compare
- Reacting to sound~150 ms
Simple auditory reaction is about 150 ms — faster than reacting to light.
Source - F1 driver at the start~200 ms
Formula 1 drivers react to the start lights in roughly 150–200 ms.
Source - Blink of an eye~100 ms
A single blink takes about 100–150 ms — close to your fastest possible reaction.
Source
About this test
This reaction time test measures how quickly you respond to a visual signal. Wait for the red panel to turn green, then tap or press the spacebar as fast as you can. We time the gap with a high-resolution clock and average five rounds, ignoring any false starts. It's a fun way to feel just how fast — and how slow — a few hundred milliseconds really is.
Frequently asked questions
What is a good reaction time?
For a simple visual reaction, anything around 250 ms is normal. Under 200 ms is very fast, and consistent times below 180 ms are exceptional. Most people land between 200 and 300 ms.
Why did it say "Too soon"?
If you tap before the screen turns green, that's a false start. We can't measure a reaction to a signal that hasn't happened yet, so that round is repeated. The wait before green is randomized so you can't anticipate it.
How is the time measured?
We use the browser's high-resolution clock (performance.now()) to record the instant the screen turns green and the instant you respond. The difference, in milliseconds, is your reaction time. Screen refresh and input lag add a few milliseconds, so treat results as a fun estimate.
How can I react faster?
Stay rested, focused and warmed up, and anticipate that the signal will come without jumping the gun. Reaction time naturally slows with fatigue, alcohol and age, and improves a little with practice — but everyone has a biological floor of around 150 ms.
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