What this headphone test checks
Five short listening tests, made live in your browser with nothing to download. Put your headphones on, set the volume to about a third, and run them in any order. The earcups above glow with the sound actually leaving the page, so you can see which channel is playing while you listen.
- Left and right. This left right audio test should be unmistakable: left only in your left ear, right only in your right, centre in the middle of your head.
- Stereo sweep. A stereo test that glides from ear to ear. It should move smoothly. A jump, a gap or a dull side points to a balance setting or a weak driver.
- Bass test. A tone rises from 20 to 200 Hz. Press “I can hear it” when it appears to see how low your headphones reach at your volume.
- Hearing range. A tone climbs to 20 kHz. Press “I can’t hear it” when it fades. With the bass test, that gives the range you hear on this pair.
- Phase test. The same noise in both ears, matched and then with one side flipped. It catches a side wired backwards.
Left and right swapped, or one side silent?
Check your headphones in this order.
- Make sure you are wearing them the right way round. Most pairs mark L and R inside the band or the earcup.
- Push the plug all the way in and try without any adapter or extension. A plug that sits halfway can play one side only, or both sides faintly with the voice missing.
- On Windows 11, open Settings > System > Sound. Turn Mono audio off, then select your headphones and check that the Left channel and Right channel sliders match.
- On a Mac, open System Settings > Sound > Output and centre the Balance slider. Then open Accessibility > Audio and turn off Play stereo audio as mono.
- Try the headphones on your phone. If the fault follows them, it is the cable or a driver. If it stays with the computer, it is the port or a setting.
A detachable cable is an easy swap. A driver that has gone silent is usually the end of the pair; when it’s time, the headphone finder matches new ones to how you listen.
Bluetooth headphones that suddenly sound thin
Bluetooth headsets have two modes. Headphone mode plays full stereo. Headset mode, also called hands-free, turns the mic on and drops the sound to narrow mono made for calls. If the left test plays in both ears, or music sounds like a phone call, that is what happened.
The cause is almost always an app using the headset’s mic: Discord, Zoom, Teams or a browser tab. On Windows, pick the output called Headphones or Stereo, not Headset or Hands-Free. On a Mac, set System Settings > Sound > Input to the built-in microphone so the headphones stay in stereo. Check whichever mic you end up with in our mic test.
What the bass test tells you
Deep bass needs a seal: over-ear pads closed around your ears, earbuds filling the ear canal. If the tone only appears around 80 or 100 Hz, press the earcups gently to your head or try a larger ear tip, then run it again. If the number drops a lot, the fit was the problem, not the headphones.
As the tone climbs, listen for buzzing or a rattle at one spot. That usually means a loose part, a damaged driver or something touching the earcup. Laptop speakers and earbuds that don’t seal often start above 100 Hz. Our ears are also less sensitive to deep bass, so at low volume you may not hear 20 to 30 Hz even on headphones that can play it.
Hearing range and the high sweep
The textbook range of human hearing is 20 Hz to 20 kHz, but that describes young ears. The top end falls gradually with age, and most adults lose the tone well before 20 kHz. Many headphones and most laptop speakers roll off at the top too. So your result is the range you hear on this pair at this volume, not a hearing test. If you notice a real change in your hearing, see a doctor or an audiologist.
What a phase test reveals
When both drivers push and pull together, sound feels solid and sits in the middle of your head. When one side is wired backwards, they work against each other: the sound spreads out, seems to come from around you, and the bass thins. If “In phase” sounds hollow and “Out of phase” sounds full and centred, one side is reversed, usually after a repair, a new cable or an adapter.
Keep the volume sensible
None of these tests needs loud sound. High tones can feel sharp even when they seem quiet. Press Stop or Escape whenever you want silence. On a loud commute, noise cancelling lets you listen quieter; our best noise cancelling headphones guide is a good start.
Questions
Why do I hear the left test in both ears?
Mono audio is on, the plug isn’t fully in, or a Bluetooth headset is in hands-free mode. Some speakers and soundbars also mix the channels.
Is this headphone tester accurate?
The sounds are exact: each channel test feeds one channel only, and the earcups light from the real output. Your device, settings and ears still shape what you hear, so treat the numbers as a practical check.
Why can’t I hear 20 Hz?
Few people hear 20 Hz at a comfortable volume, and many headphones barely play it. Improve the seal, but don’t turn it up just to chase a number.
Does it work on speakers and phones?
Yes. For speakers, sit centred between them; the phase test also finds a speaker with its wires swapped. On an iPhone that plays nothing, check the silent switch. Phone speakers can’t play deep bass, so use headphones for the bass test.