Speed & Neural Processing
Reaction Time FAQ
Everything about human reaction time — what affects it, how it's measured, who is fastest, and how to improve yours. Take the free Reaction Time test to find out where you stand.
What is simple reaction time?
Simple reaction time is the time between a single expected stimulus (like a green light) and your physical response. It is the purest measure of neural processing speed.
What is the fastest human reaction time ever recorded?
The fastest verified simple visual RT is around 101ms, achieved in controlled lab conditions. Typical elite performers (F1 drivers, professional gamers) average 150–180ms.
Do gamers have faster reaction times than non-gamers?
Yes — action gamers average 15–20ms faster than non-gamers on visual RT tasks. Multiple controlled studies confirm this and show the effect transfers beyond gaming.
Does caffeine improve reaction time?
Yes, modestly. 100–200mg of caffeine reduces simple RT by ~10ms on average. The effect is stronger in non-habitual users and peaks ~45 minutes after consumption.
What is the difference between reaction time and a reflex?
A reflex is an involuntary spinal-cord response that bypasses the brain (e.g. knee-jerk). Reaction time involves conscious brain processing. Reflexes are faster (~20ms) but not controllable.
Why is reaction time important in sports and driving?
In driving, 100ms of faster RT can mean 3 metres of stopping distance at 100km/h. In sports, it determines who reaches the ball first. It is one of the strongest predictors of athletic performance.
What factors affect reaction time?
Age, sleep quality, caffeine, alcohol, stress, temperature, practice, and stimulus type all affect RT. Sleep deprivation alone adds ~50ms. Alcohol at 0.08% BAC adds ~30ms.
Does being tired slow your reaction time?
Significantly. After 17–19 hours awake, RT impairment equals 0.05% blood alcohol. After 24 hours without sleep, impairment approaches 0.10% BAC — above legal driving limits in most countries.
How is reaction time measured?
In labs: a stimulus triggers a hardware timer that stops when the subject responds. Online: performance.now() in JavaScript provides ~1ms precision. Both subtract any display or input latency.
What is a good reaction time for an athlete?
Elite sprinters leave the blocks in ~130ms after the gun. F1 drivers average ~200ms. MLB batters have ~400ms to decide on a pitch. "Good" varies enormously by sport and stimulus type.
Why Reaction Time Matters
Reaction time is one of the most studied variables in cognitive science. It predicts athletic performance, driving safety, gaming skill, and general cognitive processing speed.
This FAQ covers the questions most commonly asked about human RT — from the basics of what it measures to sports-specific benchmarks and the science of how caffeine, sleep, and practice change your score.
Every answer is backed by published research. Use the Reaction Time test to get your baseline, then return to track your improvement.
Reaction Time by Group
| Group | Avg RT | Top score |
|---|---|---|
| General population | 250–270ms | ~150ms |
| Casual gamers | 230–250ms | ~140ms |
| Pro esports players | 150–180ms | ~120ms |
| F1 drivers | ~200ms | ~150ms |
| Elite sprinters | ~130ms (gun RT) | n/a |
Find out how fast you really are
Take the free Reaction Time test — no account needed, results in 60 seconds, instant percentile ranking.