Reaction Time Test

Measure how quickly you react to an unpredictable visual signal.

Reaction Time Test

This test measures how fast you respond when a red screen turns green. One run is five rounds, and your result is the average of those five reaction times in milliseconds. Lower means faster, and the leaderboard puts the lowest averages first.

There is no difficulty choice. The signal timing for each round comes from a value the server issues for that attempt, so there is no fixed rhythm to learn.

How a run plays out

Press the grey pad to begin and it turns red, which means wait. After a random delay somewhere between 2 and 8 seconds it turns green, a prompt tells you to click, and with sound on you also hear a short beep. Respond, and your round time shows on a blue screen, a chip such as R1 or R2 is added underneath, and the running average at the top updates.

The blue screen stays up for about 1.4 seconds before the pad goes red again. Pressing during that pause does nothing, so relax your hand there. After the fifth response the pad shows your average and the result goes off for verification.

False starts and runs that do not count

Press while the pad is red and it turns orange: a false start. That ends the whole run, not just the round, so any good times you already had are gone and you start over with the retry button.

Not every press after the signal counts either. If any single round comes in under 80 ms or over 10 seconds, the run is not accepted for the leaderboard, so a lucky guess that lands just after the green appears is worthless. Since the delay is drawn again every round, pressing to a rhythm mostly raises your chance of a false start.

Why the input method changes your number

A click or tap on the pad registers when you release it. Space and Enter register the instant the key goes down. With a mouse, a short, sharp click keeps the number lower than a slow press, and a keyboard takes the release out of the measurement altogether.

Your hardware adds its own delay too. Screens, mice, keyboards and touch panels all differ, so compare results from the same device and input only. A steady average over several runs says more than one unusually quick attempt. This is a casual measuring game, not a medical test or a driving assessment.

Controls

Start and respond by clicking or tapping the pad, or with Space or Enter. Buttons at the top toggle sound and switch the in-game text between Korean and English; it opens in Korean only if your browser language is Korean.