Reaction Time Tool

Sound Reaction Time Test

Nothing to watch. A tone plays at a random moment and the clock stops when you respond. Turn your sound on, and try it with your eyes shut.

    Why you are faster to a sound than to a light

    Almost everybody records a quicker time here than on the standard visual test, typically by 20 to 40 milliseconds. The reason is anatomy rather than skill. Sound arriving at the ear is converted to a nerve signal almost immediately and reaches auditory cortex in something like 8 to 10 milliseconds. Light hitting the retina has to go through a chemical cascade in the photoreceptors before anything travels anywhere, and that alone costs 20 to 40 milliseconds before the signal starts its journey.

    This is not a small curiosity. It is why sprint races start with a gun, why reversing sensors beep rather than flash, and why an alarm you can hear wakes you when an alarm you can only see does not.

    Getting a clean measurement

    Audio adds one source of error that the visual tests do not have: the delay between the browser deciding to play a tone and the sound leaving your speakers. Wired speakers and wired headphones add a handful of milliseconds and can be ignored. Bluetooth is a different matter. Wireless audio codecs buffer heavily, and 100 to 200 milliseconds of latency is normal, which will make your score look far worse than you are. If you are on Bluetooth, switch to wired or to the device speakers before reading anything into the number.

    The tone is a short 880 Hz sine wave, chosen because it is easy to hear across cheap speakers and phone hardware without being unpleasant. Your browser will not let it play until you have interacted with the page, which is why the test only arms after your first click.

    Try it with your eyes closed

    This is the one test on the site that works better without looking. On a visual test there is always something to watch, and watching invites anticipation: you start reading rhythm into the delay and eventually you jump. Close your eyes, rest a finger on the space bar, and there is nothing to guess from. A lot of people set their fastest time of the day this way.

    It also makes the test usable by people who cannot take the visual version at all, which the standard reaction test on most sites quietly excludes.

    Where this sits in the set

    Sound reaction is the fastest of the simple reaction tests, so treat your number here as your floor rather than your typical speed. For the visual equivalent use the reaction time test. For a version with real anticipation pressure built in, the F1 start lights test holds you for up to three seconds before the signal. And for something closer to what a game demands, where you have to find a target as well as react to it, use the aim trainer.

    All the tests

    Reflex and speed

    Memory and attention

    Reading

    Frequently Asked Questions

    Is auditory reaction time faster than visual reaction time?
    Yes, consistently. Most people react to a sound roughly 20 to 40 milliseconds quicker than to a light. A sound reaches the auditory cortex in about 8 to 10 ms, while a visual signal needs 20 to 40 ms just to get through the retina and optic pathway. The gap is physical, not a matter of training.
    Why do sprint races start with a gun rather than a light?
    Because auditory reaction is faster and more consistent, and because a sound reaches every lane at the same instant while a light has to be seen. Athletics rules treat any response quicker than 0.1 s after the gun as a false start, on the basis that nobody can react that fast.
    Do I need headphones for this test?
    No, speakers are fine. Headphones remove a couple of milliseconds of air travel and usually make the tone easier to catch in a noisy room, but the difference is small compared with the variation between your own attempts. Bluetooth headphones are the exception: wireless audio latency can add 100 ms or more and will wreck the measurement.
    Nothing plays when I start the test
    Browsers block audio until you interact with the page, which is why the test only arms after you click. If you have started and still hear nothing, check that the tab is not muted, that your system volume is up, and that no other application has taken exclusive control of the audio device.
    Can I take this test with my eyes closed?
    Yes, and it is worth trying. With nothing to look at there is no visual cue to accidentally anticipate, and many people record their fastest times this way. Use the space bar rather than the mouse so you do not have to aim.