Reaction Time: 2 Player Duel

Wait for green, then tap. This reaction time test tells you how fast you reacted, in milliseconds, and shows exactly how it got that number.

A run is five tries. You see each time, your average, your fastest try and how steady you were, plus a percentile against typical players. Tap too early and that try doesn't count.

SIX WAYS TO TEST YOUR REFLEXES
• Classic: the screen turns from red to green, tap as fast as you can
• Start lights: five red lights come on one by one, tap the moment they all go out
• Go or no go: tap on green, hold back on blue
• Sound: tap when you hear the beep while the screen stays the same
• Vibration: tap when the phone buzzes in your hand
• 2 player duel: one phone, half the screen each, first to 3 points wins

HOW A TAP IS TIMED
The colour changes in a single frame. There is no fade and no countdown. The clock starts at the screen refresh where the green can first appear, and your tap is timed with the timestamp the touchscreen records when your finger lands, not when the app gets around to it. Taps under 100 ms count as too early, because nobody reacts that fast.

Every phone adds a few milliseconds in its screen and touch hardware. That delay only makes times slower, never faster, and it's the same on every try, so your progress on one phone stays fair to compare. The app explains the whole method under Settings.

WATCH YOURSELF GET FASTER
Stats for each mode show your best average, your fastest try, a chart of your last 10 runs and your full history. The percentile curve shows where your recent average sits among typical players. It's a model calculated on your phone, so treat it as a rough guide.

2 PLAYER DUEL
Put the phone on the table between you. The top half is turned around for the player across from you, and both halves go green in the same frame. Tap before green and the point goes to your friend. It's the quickest 2 player reaction game I could make: no setup, first to 3 wins.

ALSO INCLUDED
• Every mode is free to play and nothing is locked
• There are never ads on a test screen
• Works offline, with no account and no sign in
• Your times are saved on your phone, not on our servers
• Dark and light theme
• Available in 16 languages

About ads: Reaction Time is free to download and supported by ads. A small banner shows on the home screen and the stats screen. Now and then a full screen ad may appear when you leave the results of a finished run, never during a test. If a run went badly, you can choose to watch a short video so it doesn't count in your history. A one time purchase removes the ads.

A tip for steady results: sit comfortably, keep your finger just above the screen and use the same finger each time. Sound mode works best with the phone speaker or wired headphones.

Ready? Wait for green.

Recent changes:
First release of Reaction Time: a classic wait for green test, start lights, go or no go, sound and vibration tests and a 2 player duel on one phone. Five tries per run, your average, best and percentile, stats and history. Every test is free and there are never ads during a test.