Reaction Time Test.
Measure how fast you react in milliseconds. Wait for the box to turn green, then click or press a key as quickly as you can — nothing is uploaded.
Click the box to start, wait for it to turn green, then click or hit any key as fast as you can. Clicking before green counts as a false start.
Your times
Reaction ratings
Before you start
- React, don't guessWait until you actually see green. Clicking on a rhythm or anticipating the change gives a fake sub-150ms score, not your real reaction time.
- Take several goesA single attempt is noisy. Do 5–10 and watch the rolling average — it's a far steadier read than any one click.
- Mind your displayA 60Hz screen can add up to ~16ms before you even see the green. On a high-refresh monitor you'll naturally score a little faster.
- Go wired if you canWireless input and USB hubs can add latency. A direct wired mouse or keyboard gives the cleanest, most repeatable number.
How to test your reaction time
- 1Click to startClick the box (or press a key) — it turns red while it waits a random moment.
- 2Wait for greenKeep still. If you click while it's red, it's a false start and you simply try again.
- 3React the instant it's greenClick or hit any key as fast as you can the moment the box flips to green.
- 4Compare your averageYour time, best, and last-5 average appear on the right. Repeat to push your average down.
What is reaction time?
Reaction time is how long it takes you to respond to something you see — here, the gap between the box turning green and you clicking or pressing a key. It's measured in milliseconds (ms), and it captures the whole chain: light hits your eye, your brain recognises the change, and your hand fires the movement. For a simple visual signal like this, most people land between 200 and 300 ms.
Your result depends on more than raw reflexes. A fast keyboard or mouse, a high-refresh-rate monitor, and low input lag all shave off milliseconds, while a tired brain, a slow display, or anticipating the green (and jumping early) all skew the number. Because a browser can only time from when it paints the green frame, treat this as a fun, repeatable benchmark of *your setup plus you* rather than a clinical measurement. Take several goes and watch your average — it's steadier than any single attempt.
When a reaction test helps
Gaming benchmark
Track the reflexes that matter in shooters and fighting games, and see if a new mouse or monitor actually helps.
Comparing hardware
Run it on two setups — wired vs wireless, 60Hz vs 144Hz — to feel how much your gear adds to the number.
Warm-up & focus check
A quick way to tell whether you're sharp or sluggish before a match, exam, or long session.
Reaction-time terms
- Reaction time
- The delay between a signal appearing and your response — measured here in milliseconds from green to click.
- Millisecond (ms)
- One-thousandth of a second. Human visual reactions live in the 150–300ms range.
- False start
- Responding before the go signal. It's not a real reaction, so the test discards it and asks you to retry.
- Input lag
- Delay added by your mouse, keyboard, cable, or OS between your action and the computer registering it.
- Refresh rate
- How often your monitor redraws per second (Hz). Higher rates show the green signal sooner.
- Simple vs choice reaction
- This is a simple reaction (one signal, one response); choice reactions, where you pick between options, are slower.
Frequently Asked Questions
What is a good reaction time?
For a simple visual click test like this, an average around 200–250 ms is good, and consistently under 200 ms is excellent — that's roughly the range top gamers and athletes hit. The worldwide average is about 250–270 ms. Anything under 150 ms on a click test usually means you anticipated the green rather than truly reacted to it.
Why is my reaction time so slow / getting worse?
Common causes are fatigue, distraction, a slow or high-latency display, and input lag from wireless devices. Reaction time also naturally rises when you're tired or later in the day. Try a few warm-up rounds, use a wired mouse or keyboard, and take your best average of several attempts rather than judging a single slow one.
Does my monitor or keyboard affect the result?
Yes. A 60 Hz monitor can add up to ~16 ms before you even see the green, while a 144 Hz+ display shows it sooner. A high polling-rate keyboard or mouse and low input lag also trim a few milliseconds. That's why the same person scores differently on different setups — the test measures you *and* your hardware together.
How can I improve my reaction time?
Warm up first, stay relaxed but focused, and remove distractions. Getting enough sleep, good lighting, and a fast wired setup all help. Practice makes your responses more consistent, though everyone has a physical floor — you can sharpen consistency more than you can lower the raw minimum.
Can I test reaction time with the keyboard?
Yes — this tool counts a key press just like a click, so you can react with your spacebar or any key. Some people are a hair faster on the key they use for gaming. Try both and compare your averages.