How do I test my left and right headphones?

Keep the volume low, put the headphones on and press Play left. The tone should come from the left earpiece only. Then press Play right. If the sides are swapped or both play together, check the connector, the balance setting and any mono-audio option.

How do I know the page is really sending sound to one channel?

The Left and Right meters show the level the page is sending to each channel. If the meter moves on the side you chose but you hear nothing, the problem is in the speaker, cable or system settings, not in the page.

What do the test tones do?

They play one steady pitch so you can check a part of the range: 60 and 100 Hz for deep bass, 440 Hz and 1 kHz for the middle, 4 kHz where hearing is most sensitive and 10 kHz for the top end. A missing or very quiet tone points at a limit of the speaker.

What is the frequency sweep?

A tone that rises smoothly from 20 Hz to 20,000 Hz over 15 seconds. It shows where the tone becomes audible and where it fades, which is the range your speakers and ears can handle. Fading at the very top is normal for many adults.

Why can I not hear the lowest tones?

Small speakers, such as those in laptops and phones, usually cannot reproduce the deepest bass. Headphones or larger speakers can. A quiet or missing 60 Hz tone on a small speaker is expected.

How loud does the test play?

At the default volume of 25% the tone is about 24 dB below the loudest the page can play, and 50% is about 12 dB below. Tones sound louder than music at the same setting, so raise the volume slowly, especially with headphones.

Does the sound test work on a phone?

Yes, in current mobile browsers. Tap a button to start, because phones only allow sound after a tap. Turn the phone's silent switch off and its media volume up.

Is anything downloaded or uploaded?

No. Every tone is generated by your browser, so there is nothing to download and nothing to upload. The test is free with no account.

Sound Test — Left and Right Speaker, Headphone Test, Free

Test your speakers and headphones online: left and right channel test, test tones from 60 Hz to 10 kHz, and a 20 Hz to 20 kHz sweep. Free, no upload.

Last updated: 8 October 2026

Start with the volume low, especially with headphones. Test tones and the sweep can be loud at the very low and very high ends.

Volume25%

Left and right speaker test

A tone plays in one speaker only. If you hear it on the wrong side, or in both, your headphones or speakers are crossed or mono.

Test tones

Low tones (60 and 100 Hz) test bass; 10 kHz tests the top end. Small speakers will not reproduce the lowest tones.

Frequency sweep

A tone that rises smoothly from 20 Hz to 20,000 Hz over 15 seconds. Note where it fades in and where it disappears: that is the range your speakers and your ears can handle.

Nothing is playing.

Left

Right

All sounds are generated on your device. Nothing is downloaded or uploaded.

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Check both channels and the whole frequency range

Plug in your headphones or speakers and press Play left, then Play right. The tone should come from one side at a time, and two meters show what is being sent to each channel. Test tones and a frequency sweep check the bass and treble as well. Every sound is made on your device, so nothing is downloaded or uploaded.

The left and right test

Each button plays a tone in one speaker only, or in both. If the tone you expect on the left comes out of the right, or comes out of both, something is crossed or collapsed to mono: a plug that is not fully in, a balance setting, a mono-audio accessibility option, or a faulty cable. The Left and Right meters show what the page is sending, so a silent side with a moving meter points at the headphones, not the page.

What the test tones show

60 and 100 Hz are deep bass, which small laptop and phone speakers usually cannot reproduce. 250 Hz is low-mid, 440 Hz is the A that orchestras tune to, 1 kHz is a common midrange reference, 4 kHz sits where hearing is most sensitive, and 10 kHz tests the top end. A tone that is missing, much quieter than its neighbours, or buzzing points at a limit or a fault in the speaker.

The frequency sweep

The sweep rises smoothly from 20 Hz to 20,000 Hz over 15 seconds, which is the nominal range of human hearing. It climbs about 1.5 seconds per octave, so the bass passes slowly and the treble seems to rush. Notice where the tone appears and where it fades: that shows the range your speakers can produce and your ears can hear. Hearing at the top end usually falls with age, so a silent last few seconds is normal.

Volume and safety

The volume control starts at 25%, which is about 24 dB below the loudest the page can play, and 50% is about 12 dB below it. Keep it low with headphones and raise it gradually, because tones and sweeps sound louder than music at the same setting. If you also need to check the other side of a call, use the microphone test and the webcam test.

Frequently asked questions

How do I test my left and right headphones?: Keep the volume low, put the headphones on and press Play left. The tone should come from the left earpiece only. Then press Play right. If the sides are swapped or both play together, check the connector, the balance setting and any mono-audio option.
How do I know the page is really sending sound to one channel?: The Left and Right meters show the level the page is sending to each channel. If the meter moves on the side you chose but you hear nothing, the problem is in the speaker, cable or system settings, not in the page.
What do the test tones do?: They play one steady pitch so you can check a part of the range: 60 and 100 Hz for deep bass, 440 Hz and 1 kHz for the middle, 4 kHz where hearing is most sensitive and 10 kHz for the top end. A missing or very quiet tone points at a limit of the speaker.
What is the frequency sweep?: A tone that rises smoothly from 20 Hz to 20,000 Hz over 15 seconds. It shows where the tone becomes audible and where it fades, which is the range your speakers and ears can handle. Fading at the very top is normal for many adults.
Why can I not hear the lowest tones?: Small speakers, such as those in laptops and phones, usually cannot reproduce the deepest bass. Headphones or larger speakers can. A quiet or missing 60 Hz tone on a small speaker is expected.
How loud does the test play?: At the default volume of 25% the tone is about 24 dB below the loudest the page can play, and 50% is about 12 dB below. Tones sound louder than music at the same setting, so raise the volume slowly, especially with headphones.
Does the sound test work on a phone?: Yes, in current mobile browsers. Tap a button to start, because phones only allow sound after a tap. Turn the phone's silent switch off and its media volume up.
Is anything downloaded or uploaded?: No. Every tone is generated by your browser, so there is nothing to download and nothing to upload. The test is free with no account.