How fast are you, really?
Three quick tests, instant results: your reaction time in milliseconds, your typing speed in WPM, and how many digits your short-term memory can hold. Free, no sign-up, nothing leaves your browser.
⚡ Reaction time test
Click or tap to start. Wait for the box to turn green, then click as fast as you can. Clicking too early restarts the round.
Best
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Average (all attempts)
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Attempts
0
Recent attempts
- No attempts yet — your history is stored only in this browser.
About the percentile: ReflexLab collects no visitor data, so the “faster than X%” figure is a model estimate from a fixed reference model (reaction times assumed log-normally distributed, median 265 ms, sigma 0.22 — parameters shown so you can judge it), not live global data. The comparison against your own attempts uses your real local history.
⌨️ Typing speed test
Type the passage below. The timer starts on your first keystroke and stops when the passage is complete. Net WPM = (correct characters ÷ 5) ÷ minutes.
WPM
0
Accuracy
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Time
0.0s
🧠 Short-term memory test
Digits flash one at a time. Remember the whole sequence, then type it back. Each stage adds one more digit. How far can you get?
Stage 1 · 3 digits
?
Press start when you are ready.
Best stage
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Best sequence length
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Frequently asked questions
Is ReflexLab free?
Yes. All three tests are free to use, supported by ads, with no sign-up and no downloads.
What is a good reaction time?
Our reference model assumes a typical tap/click reaction around 250–280 ms. Anything under 200 ms is quick, and under 150 ms is rare. Your screen and mouse add a few milliseconds, so compare your own attempts against each other.
Is the percentile real global data?
No — and we say so on the result itself. ReflexLab has no server and collects nothing, so the percentile is an estimate from a fixed, documented reference model (labeled “Model estimate”), not live data from other visitors. The percentile against your own past attempts is computed from your real local history.
Do you store my results?
Results are kept only in your own browser's local storage so you can see your history and averages. Nothing is sent to a server. Clearing your browser data erases them.
How is typing WPM calculated?
Net WPM = (correct characters ÷ 5) ÷ minutes elapsed, the standard formula. We also show your accuracy: correct characters divided by all characters typed.
ReflexLab runs entirely in your browser — fast, free, no sign-up.