What does the reaction time test measure?

Average reaction time in milliseconds across your attempts. How fast can you react when the screen changes?

How do I do well on the reaction time test?

Press start and wait. Do not click early. The moment the panel turns green, click it. Repeat five times to build an average. Reaction time depends on your screen, your mouse or finger, your browser and how tired you are. Treat this as a fun measurement, not a medical one.

Is my score saved, and can I compare it?

Your best score is stored on your own device, so you can come back and beat it. Under a minute. Take it a few times before trusting one number.

Mondo Knows Challenges

Reaction Time Test

The screen stays red until it turns green, then you click as fast as you can. Mondo times the gap in milliseconds and averages your attempts. It is the simplest way to see how quickly you respond to something unexpected.

⚡ Measures: Average reaction time in milliseconds across your attemptsUnder a minute

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How it works

Press start and wait. Do not click early.
The moment the panel turns green, click it.
Repeat five times to build an average.
Your best and average are shown at the end.

Worth knowing

Reaction time depends on your screen, your mouse or finger, your browser and how tired you are. Treat this as a fun measurement, not a medical one.

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Questions people ask

What does the reaction time test measure?: Average reaction time in milliseconds across your attempts. How fast can you react when the screen changes?
How do I do well on the reaction time test?: Press start and wait. Do not click early. The moment the panel turns green, click it. Repeat five times to build an average. Reaction time depends on your screen, your mouse or finger, your browser and how tired you are. Treat this as a fun measurement, not a medical one.
Is my score saved, and can I compare it?: Your best score is stored on your own device, so you can come back and beat it. Under a minute. Take it a few times before trusting one number.

Facts behind the reaction time test

The star-nosed mole snout holds 22,000 microscopic touch organsStar-shaped snout rays identify and consume insect prey in milliseconds.Goblin sharks shoot their jaws outward to catch deep-sea preyElastic ligaments catapult goblin shark jaws forward at high speed.Goosebumps are caused by tiny hair follicle muscles contractingArrector pili muscles pull skin hairs upright in response to cold or emotion