Reaction Time Test - Check Your Reflexes in Milliseconds

How the reaction time test works

Click the pad to start. It turns red. After a random wait between 1.5 and 5 seconds, it turns green. Click the instant you see green. The time between green appearing and your click is your reaction time in milliseconds. Five rounds make one test, and your average is saved in this browser so you can track progress.

The random delay comes from your browser's cryptographic random generator, so you can't learn the rhythm and anticipate it. Click before green and the round is marked Too soon and repeated. Guessing doesn't pay.

Timing starts on the animation frame where the green is painted and stops on the pointer-down event, not the full click. That shaves off the 50 to 100 milliseconds a mouse button takes to travel down and back up, which many other tests silently include.

What's a good reaction time?

For a simple visual test like this one, most adults average 200 to 300 ms. The median across large online datasets sits around 250 to 275 ms. Under 200 ms is fast. Competitive gamers and sprinters often land between 150 and 200 ms. Anything consistently below 120 ms usually means anticipation, not reaction; the brain needs time to see, decide and move.

Age matters. Reaction time is quickest in the late teens and twenties and slows by roughly a few milliseconds per year after that. Sleep, caffeine, alcohol, fatigue and distraction all move the number more than age does. A 45-year-old who slept well can beat a tired 20-year-old.

Your hardware is part of the score

Every test like this measures you plus your equipment. A 60 Hz display only updates every 16.7 ms, so green can appear up to one frame late. A 144 Hz or 240 Hz gaming monitor cuts that to 7 or 4 ms. Wireless mice, Bluetooth keyboards and some touch screens add 10 to 40 ms of input lag. TVs in non-game mode can add 50 ms or more.

So compare scores on the same device. A 230 ms average on your phone and 210 ms on your gaming PC might be the same reflexes. If you're chasing a personal best, use a wired mouse, a high refresh rate screen and a browser with no other heavy tabs.

How to get faster

Warm up with a few rounds before you record a test; your first two tries are almost always your slowest. Rest your finger lightly on the button so the press is the only movement. Look at the center of the pad, not the edges. And don't try to predict green, since early clicks reset the round and break your focus.

Real improvement comes from sleep, fitness and practice at a specific task. Generic reaction training plateaus quickly: most people improve 10 to 30 ms over the first few sessions, mostly by learning the test, then level off. That plateau is your real number.

Keyboard, touch and accessibility

Mouse, touch, Space and Enter all count. Keyboard presses are usually 10 to 20 ms quicker than a mouse, so note which one you used when comparing. On phones, tap with your index finger rather than your thumb for more consistent times.

The test depends on seeing a red-to-green change. The pad text also changes from “Wait for green” to “CLICK!”, which helps if red and green look similar to you. If you have photosensitive epilepsy, note that the test involves sudden full-panel color changes.