Reaction Time Test

What is Reaction Time?

Reaction time is the interval between a sensory stimulus (like a visual change) and your motor response (clicking). For visual stimuli, this involves: light hitting your retina → optic nerve firing → visual cortex processing → motor cortex commanding → nerve impulse to your finger muscles → physical button press.

This full loop takes a minimum of roughly 100ms even in ideal conditions. The human physiological floor for visual reaction time is approximately 100–120ms.

What Affects Your Score?

• Sleep and fatigue — Sleep deprivation can add 50–100ms to your reaction time.
• Age — Reaction time peaks in your early 20s and gradually increases afterward.
• Monitor refresh rate — A 60Hz monitor adds up to 16.7ms of display lag vs. 4.2ms on 240Hz.
• Mouse polling rate — 125Hz adds up to 8ms of click latency vs. 1ms at 1000Hz.
• Caffeine — Moderate caffeine intake can reduce reaction time by 10–20ms.
• Practice — Familiarity with the specific stimulus and response reduces cognitive processing time.

Browser vs. Dedicated Software

Browser-based reaction tests add a small amount of latency from JavaScript event processing (typically 1–5ms). This test uses performance.now() for high-resolution timing which minimizes this overhead. Results are consistent across repeated tests even if the absolute value is slightly higher than hardware-level measurement.

VALORANT & CS2 (FPS)

In first-person shooters, reaction time is the gap between seeing an enemy and clicking. A 200ms reaction time means you begin your aim adjustment 200ms after spotting a target. At 240fps on a 240Hz monitor with a 1ms mouse, total system latency adds roughly 5–8ms on top of your biological reaction time — making hardware upgrades less impactful than raw reaction training at this level.

Pro VALORANT players average 170–210ms on tests like this, but in-game times appear faster because of pre-aim, game sense, and pattern recognition that reduce the cognitive processing portion of the reaction.

Fighting Games (Street Fighter, Tekken)

Fighting games run at 60fps, meaning each frame is 16.7ms. The tightest reaction windows — blocking a low attack, punishing a whiffed move — are often 2–4 frames (33–67ms). These windows are below human reaction time. Elite fighting game players survive by reading patterns, conditioning opponents, and using muscle memory, not pure reaction.

Battle Royale (Apex Legends, Warzone)

Battle royale games have more forgiving reaction windows than pure FPS due to larger hitboxes and lower time-to-kill. A 250ms reaction time is competitive. Movement prediction and pre-aiming matter more than raw reaction speed. Focus on consistent aim training over shaving milliseconds off your reaction time.

Racing Games & Rhythm Games

Rhythm games like osu! train reaction time specifically for visual stimuli, making them excellent practice tools. Top osu! players demonstrate sub-160ms reaction times. Racing games (F1 games, Gran Turismo) require sustained 150–200ms reaction for braking points. Both genres benefit significantly from high-refresh-rate monitors and low input latency setups.

The Full Latency Chain

Your measured reaction time is actually the sum of:

• Biological reaction time — The time for your brain to process the stimulus and send a motor signal (~100–200ms).
• Monitor display latency — 60Hz adds up to 16.7ms; 240Hz adds up to 4.2ms; 360Hz adds up to 2.8ms.
• Mouse click registration latency — 125Hz mouse adds up to 8ms; 1000Hz adds up to 1ms; 4000Hz wireless adds ~0.25ms.
• USB/OS processing — Typically 1–3ms of additional system overhead.

Total hardware latency on a typical gaming setup: 12–28ms. On an optimized esports setup (360Hz monitor, 4000Hz mouse): 3–5ms. The difference can be 20+ ms — meaningful at the top level.

How Our Test Measures Time

We use performance.now() — a high-resolution timer with sub-millisecond precision — to record the exact moment the green color is applied and the exact moment your mousedown event fires. The difference is your reported reaction time, which includes monitor display latency and mouse polling latency as described above. This is consistent with how all browser-based reaction tests work.

How to Get Your True Reaction Time

To estimate your biological reaction time from this test, subtract your estimated hardware latency:

• 60Hz monitor + 125Hz mouse: subtract ~20ms from your result.
• 144Hz monitor + 1000Hz mouse: subtract ~8ms.
• 240Hz monitor + 1000Hz mouse: subtract ~5ms.
• 360Hz monitor + 4000Hz mouse: subtract ~3ms.

Check your mouse polling rate →