What is a good reaction time? Test yours and understand the number
How fast can you respond to something you see? Reaction time is a fun thing to test — and it genuinely matters for gaming, driving, and sports. Here's what the numbers mean and how to measure yours properly.
The average, in milliseconds
For a simple visual reaction — "click when the screen turns green" — the average adult lands around 200–250 milliseconds (a quarter of a second). Under about 200 ms is fast; competitive gamers and athletes often sit in the 150–200 ms range. Below ~100 ms on a simple test usually means you guessed and jumped early.
What's actually happening in that quarter-second
Your reaction isn't instant because a chain has to fire: light hits your eyes → the signal travels to your brain → the brain processes it and decides → it sends a command to your finger → the muscle moves. Each step takes time. That biological pipeline is why sub-100 ms genuine reactions aren't humanly possible for a simple stimulus.
What affects your reaction time
- Age — reaction time is quickest in your late teens to late twenties, then gradually slows.
- Fatigue and sleep — being tired slows you noticeably.
- Caffeine and alertness — can sharpen it slightly.
- Practice — you improve at a specific task with repetition.
- Type of stimulus — sound reactions are typically a bit faster than visual ones.
Measuring it accurately
Two things throw off a reading. First, don't anticipate — if you predict the trigger you're measuring guessing, not reacting. Second, your hardware adds latency: screen refresh rate and input lag can add tens of milliseconds, so results aren't lab-perfect. To get a fair number, take several attempts and average them, and ignore the outliers where you jumped early.
Fancy testing your fingers and your screen together? Pair this with a keyboard test to rule out input lag on a specific key.