Test and train your reflexes with precision timing, multiple game modes, multiplayer arena battles, boss fights, and a full progression system. Free, no downloads, works on any device.
The screen shows an amber warning. Stay focused — the green flash can appear any moment between 1 and 5 seconds.
When the screen turns green, click, tap, or press SPACE as fast as humanly possible. Every millisecond counts.
See your reaction time in milliseconds. Earn XP, build combos, unlock achievements, and climb the leaderboards.
Each mode trains a different cognitive skill. From simple reaction time to impulse control and focus under pressure.
The standard reaction time test. Wait for green, click as fast as you can.
React to sound cues instead of visual signals. Audio reactions are naturally faster.
10 rapid-fire reactions in a row. Your average across all rounds is your score.
React to GREEN signals only. Do NOT react to RED. Tests impulse control.
Distracting elements float across the screen. Can you stay focused amid chaos?
Compete with up to 8 players in real-time. 7 unique arena modes including Battle Royale.
The average human reaction time to a visual stimulus is approximately 250 milliseconds. Here is how different speeds compare.
Exceptional
< 150ms
Excellent
150–199ms
Great
200–249ms
Average
250–299ms
Below Average
300–349ms
Slow
350–499ms
Very Slow
500ms+
Every reaction earns XP. Build combos for multiplied rewards, complete daily challenges, and unlock themes and achievements.
Earn XP with every reaction. Faster reactions earn more. Progress through 100 levels from Rookie to Legend, unlocking new themes, sound packs, and boss battles along the way.
Chain fast reactions together to build combo multipliers — up to 5x XP. Stay under the threshold to keep your streak alive. One slow reaction resets everything.
Over 20 achievements to unlock — from getting your first reaction under 200ms to completing 1000 total reactions. Daily challenges offer bonus XP rewards.
The average human reaction time is around 250 milliseconds (ms). Anything under 200ms is considered fast, and professional gamers often achieve times under 150ms. With regular practice, most people can significantly improve their reaction speed.
Regular practice is key. reflexly.io offers multiple training modes — Classic, Speed Round, Audio, Inhibition, and Chaos — each targeting different cognitive skills. Consistent daily practice, proper sleep, hydration, and physical exercise all contribute to faster reflexes.
Yes. reflexly.io uses the browser's high-precision performance.now() API for millisecond accuracy. Results may vary slightly based on your device, display refresh rate, browser, and input method (mouse vs keyboard vs touchscreen), but the test provides reliable measurements for tracking progress.
No. All single-player modes work without an account — your progress is saved locally in your browser. Creating a free account lets you sync progress across devices, compete in multiplayer arena matches, and appear on leaderboards.
Single-player modes include Classic, Audio (sound cues), Speed Round (10 rapid-fire reactions), Inhibition (react to green, ignore red), Chaos (distractions), and Zen (relaxed). The multiplayer Arena offers 7 modes including Battle Royale, Hot Potato, Sudden Death, and Drunk Mode.
True visual reaction time has a biological minimum of approximately 100–120ms due to neural processing speed. Anything faster is almost certainly anticipatory — meaning you clicked before actually processing the stimulus. These are flagged to keep measurements accurate.
Reaction time is the interval between the presentation of a stimulus and the initiation of a motor response. It involves three distinct stages: stimulus detection (sensory processing in your eyes or ears), decision making (central processing in your brain), and response execution (motor output through your muscles).
Research in cognitive neuroscience has consistently shown that reaction time can be improved with practice. A 2014 meta-analysis published in Frontiers in Human Neuroscience found that regular cognitive training exercises can reduce reaction time by 10–20% over a period of weeks. Factors that influence reaction time include age, fatigue, arousal level, physical fitness, and the type of stimulus.
Audio stimuli typically produce faster reactions than visual stimuli — approximately 140ms vs 180ms for simple reactions — because auditory signals are processed more quickly in the brainstem. This is why reflexly.io offers a dedicated Audio mode for those wanting to push their limits.
The different game modes on reflexly.io are designed to train different aspects of cognitive processing: Classic mode tests simple reaction time, Inhibition mode trains executive control and impulse inhibition, Audio mode leverages faster auditory pathways, Chaos mode builds selective attention under distraction, and Speed Round tests sustained cognitive performance.
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