How to test your reaction time and read the result

Reaction time is how long it takes you to respond after something happens. An online test measures the simplest kind: you see one signal and press as fast as you can.

The fastest way

Open the Reaction Time Test and click the pad. It turns red, and after a random wait it turns green. Press the moment you see green. After five rounds you get your average, your median and your best time in milliseconds.

How to read the result

Many people land somewhere around 200 to 300 ms. Look at the median more than the average: one slow round, from a blink or a distraction, pulls the average up, while the median stays near your usual speed.

Why the number includes your equipment

The test cannot see the moment light leaves your screen or the moment your finger moves. It times from the frame where the pad turns green to the moment the browser receives your press. So the result also includes:

• your screen's refresh and processing delay (up to about 17 ms at 60 Hz, often more on TVs);
• your mouse, trackpad or keyboard's reporting delay (wireless and power-saving devices can add several ms);
• on a phone, the touchscreen's own delay.

To compare people fairly, use the same device. To compare devices, use the same person.

Getting a steady result

• Sit comfortably with your finger already resting on the button.
• Do a few practice rounds, then run a full set of five.
• Don't try to guess the timing. The wait is random, and early presses don't count.

A note on privacy

Times are measured in your browser and exist only in the open page. Nothing is stored or uploaded.

Open the Reaction Time Test →