Why does nothing change on screen at the beep?

Because then it would be a visual test with a sound on top. The stage reads Listen from your press until you respond, and only then shows the time, so what you react to is the beep alone. The beep is not announced to a screen reader either.

Do headphones change the result?

They can. The time runs from the moment the beep is handed to the device's audio system, so the delay before you actually hear it is inside the figure, and nothing is deducted for it. Bluetooth headphones usually add more of that delay than wired ones or the built-in speaker. Compare runs made with the same output.

Why did a trial say the page could not play sound?

Browsers let a page start sound only after you press something on it. The first press on the stage allows it, but if the beep was due before the browser agreed, there was no signal to react to, so the trial was not recorded and your next press runs it again. On a phone, also check the volume and any silent or mute setting.

Can I compare it with the colour test?

Yes, on the same device: run five trials of each and compare the medians. The two figures carry different device delays, the audio output's in this one and the screen's in the other, so part of any gap between them is your hardware. Each test keeps its own trials in this browser.

Is this a hearing test?

No. It times how quickly you respond to a beep you can already hear. It does not test your hearing, which pitches you can hear or how quiet a sound you can pick up.

Auditory Reaction Time Test

This is the reaction time test with the screen taken out of it. Press the stage and, after a random wait of one to five seconds, or two to eight, a short beep plays. Nothing on the stage changes when it does, so the sound is the only thing to react to. A press before the beep is a false start, and five trials give a median and a best.

Median so far

not yet

Best

not yet

Wait before signal

The stage takes a click, a tap, the space bar or Enter, and the press is what is timed, not the release. A second press in the moment after a trial ends is ignored, so a double press cannot start the next trial while you are still reading the last one. Changing the wait range cancels a trial that is waiting; the trials already recorded stay. Your times and the range you chose are kept in this browser and nowhere else.

Turn the sound on before you start. On a phone, check the volume and any silent or mute setting. Bluetooth headphones usually add more delay to every trial than wired ones or the built-in speaker, so compare runs made with the same output. The beep is not announced to a screen reader, so the sound stays the only cue.

Responded before the signala false start
the trial does not count, and the page says why
Tab hidden mid-trialthe browser stopped drawing it
the trial is voided rather than timed
0 of 5 trials donemedian: the middle time
no trials recorded yet

What the number includes. This measures the whole loop: your speaker or headphones playing the beep, your ear and hand, and the browser reporting the press. Audio output delay and input lag sit inside that figure and nothing is deducted for them, so it is comparable between your own runs on one machine rather than against a laboratory instrument. A response that cannot be a reaction is refused rather than scored: one that arrives before the signal, which had nothing to react to, and one from a trial during which the tab stopped being visible, because a browser stops painting a hidden tab.

Common questions

Why does nothing change on screen at the beep?: Because then it would be a visual test with a sound on top. The stage reads Listen from your press until you respond, and only then shows the time, so what you react to is the beep alone. The beep is not announced to a screen reader either.
Do headphones change the result?: They can. The time runs from the moment the beep is handed to the device's audio system, so the delay before you actually hear it is inside the figure, and nothing is deducted for it. Bluetooth headphones usually add more of that delay than wired ones or the built-in speaker. Compare runs made with the same output.
Why did a trial say the page could not play sound?: Browsers let a page start sound only after you press something on it. The first press on the stage allows it, but if the beep was due before the browser agreed, there was no signal to react to, so the trial was not recorded and your next press runs it again. On a phone, also check the volume and any silent or mute setting.
Can I compare it with the colour test?: Yes, on the same device: run five trials of each and compare the medians. The two figures carry different device delays, the audio output's in this one and the screen's in the other, so part of any gap between them is your hardware. Each test keeps its own trials in this browser.
Is this a hearing test?: No. It times how quickly you respond to a beep you can already hear. It does not test your hearing, which pitches you can hear or how quiet a sound you can pick up.

Timed with the browser's high-resolution clock, to the millisecond it reports. The figure includes your screen or speaker presenting the signal and your device registering the press, so it is comparable between your own runs on one machine rather than against a laboratory instrument. A ruler drop time is free-fall arithmetic, only as precise as the mark you read at the catch.