How the test works
Press Start, or Space with the box focused. The box goes dark and, after a random wait of 1.5 to 5 seconds, turns green. Click, tap or press Space the moment you see it. Your time is shown in milliseconds, and after five tries you get your average and your best. Click before it turns green and the try is flagged as too early and does not count; just go again.
What a good time is
Most people land between 200 and 300 ms on a mouse; under 200 is quick. Your screen, mouse and browser add some delay of their own, often 10 to 50 ms, so times here are a little slower than your real reflexes and only compare fairly on the same device. Touch screens are usually slower still. The clock starts on the frame the green is drawn and stops on the press itself (pointerdown), not the release.
CPS test and aim trainer
The CPS test counts every click and key press on the big box for 1, 5 or 10 seconds and gives your clicks per second. The aim trainer shows 30 targets one at a time in random places: it times each hit and counts a click that misses, for an average time and an accuracy. Your best scores are kept in this browser's local storage, so they are there next time on this device. They are never sent anywhere; clear the site's data to wipe them.
Questions
Why is my time slower than my friend's?
Different screens and mice add different delays, and a 144 Hz monitor shows the green sooner than a 60 Hz one. Compare scores taken on the same device.
Are my scores saved?
Only your best ones, in this browser's local storage, so the page can show them next time. Nothing is sent anywhere.
Does a key press count the same as a click?
Yes. Space and Enter work on every test, so you can play with the keyboard alone. Pick one and stick to it, since a key is often a little faster than a mouse button.