Speaker test
Play a short 440 Hz tone in the left channel, the right channel or both to check that stereo works and the sides are not swapped. Then run the sweep, which glides from 20 Hz to 20 kHz so you can hear where your speakers start and stop.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Turn the volume down. Start low and raise it slowly.
- Press Left, Both and Right. Each plays a 440 Hz tone for 1.5 seconds. It should come from the matching side only.
- Press Play sweep and listen. The number on screen shows the current frequency, and Stop ends the test early.
How the sweep works
The frequency rises exponentially from 20 Hz to 20 kHz over 12 seconds, so every octave takes the same time, which matches how we hear pitch. Frequency at time t is 20 × (1000)^(t / 12) Hz, so after 6 seconds it is about 632 Hz.
Tips
- Headphones. Left and right tones are a quick way to check that the cup marked L really plays on the left.
- Hear nothing at the ends? That is normal; very low notes need large speakers and very high ones fade with age.
- Laptop speakers are usually weak below about 150 Hz.
Frequently asked questions
What does the channel test show?
It plays a 440 Hz tone for 1.5 seconds on only the left channel, only the right, or both. If you hear the left tone on the right, the speakers or headphone cable are swapped.
What frequencies should I hear in the sweep?
Healthy young ears reach about 20 Hz to 20 kHz, but most speakers and headphones cover less, and hearing range falls with age. The lowest and highest parts are often faint or silent, which is normal.
Why do I hear clicks or distortion?
A very high volume can distort small speakers, especially at the low end of the sweep. Lower the system volume. The page also fades the tone in and out to avoid clicks.
Why is there no sound?
Check the system volume and the selected output device, and make sure the tab is not muted. Browsers start audio only after a click, which pressing a button here does.
Is this a calibrated measurement?
No. It is a listening check. A real frequency response needs a measurement microphone.