Hold still until the signal, then tap. Five clean taps are averaged into one figure in milliseconds. Three modes: one signal, left or right, and go or stop.
How a run works
First the pad asks you to wait. After a random pause of 1.2 to 3.6 seconds it switches and you hit it as fast as your hand allows. Jump in before the switch, or under 100 milliseconds after it, and the trial is scrapped as a false start and rerun with a fresh wait; no tap within two seconds also earns a rerun.
Your result is the average of five valid taps; lower is better. The result card also shows the median, the fastest tap and the number of false starts.
Modes
- Simple: one pad, tap when it changes.
- Left or right: two pads, tap the one that lights up. The wrong side counts as an error and the trial is repeated.
- Go or stop: tap on Tap!, hold back on Stop. A tap on Stop counts as an error.
Your device is part of the number
The time runs from the screen frame that carried the signal to the moment the browser received your tap. The browser cannot see the delay of the display itself or of a touchscreen, mouse or keyboard, and those delays differ from one device to the next by tens of milliseconds. Compare your times on the same device: a phone and a laptop give different numbers for the same hand.
Speed tactics
- Rest a finger on the pad, or on the Space bar, before the signal comes.
- Do not count the wait. It is random on purpose, and counting is how false starts happen.
- In left or right, keep one finger over each side instead of one finger in the middle.
- In go or stop, a stop needs nothing from you. Let it pass and stay ready for the next signal.
- Look at the centre of the pad, not at the edge of the screen.
Questions
The signal was there, so why a false start?
Any tap less than 100 milliseconds after the signal counts as anticipation, because nobody answers a visual signal that quickly. You just get the trial again.
Why are my times slower on my phone?
Touchscreens add their own delay before the browser hears the tap, and displays differ too. That is why a result is only comparable with runs on the same device.
Which keys work?
In simple and in go-or-stop mode, Space or Enter; in left or right, F and J or the left and right arrows.
Does the waiting time follow a pattern?
No. Every wait is drawn between 1.2 and 3.6 seconds. On ladder steps the waits are fixed by the step, but they still vary from trial to trial.
Where is the ladder?
At the Reaction Time ladder: targets in milliseconds, 20 ms quicker at each step.