How to test your speakers or headphones
This speaker test plays its sounds straight from your browser, so it works with laptop speakers, desktop speakers, a sound bar, a TV connected by cable, headphones and earbuds alike. It does not record anything and never asks for the microphone: you are the measuring instrument. Follow these steps in order:
- Turn your device volume down low, and keep the Volume slider on this page low too.
- Choose the speakers or headphones you want to test as your device's sound output.
- Press Left, then Right, and check that each sound comes only from that side.
- Press Center, then open the Phase tab: in phase should sound centered and full.
- Run the Sweep or the Bass tones to hear how low and how high your speakers go, raising the volume slowly.
Only one sound plays at a time, every sound fades in and out, and switching tabs stops whatever is playing. Stop all and the Esc key always work. The letters L, C and R start the left, center and right test from anywhere on the page.
Left and right audio test: what you should hear
The Left / Right tab plays short beeps at 600 Hz, or bursts of pink noise if you prefer a softer sound. Each beep lasts 0.25 seconds with a 0.35-second gap. Cycle moves the sound from left to center to right, three beeps in each place, so you can sit back and watch the indicator while you listen.
| What you hear | What it means |
|---|---|
| Left from the left, right from the right | The channels are correct. |
| Left comes from the right | The speakers, their cables or the headphones are swapped. |
| Both buttons sound the same, from both sides | A mono audio setting is on, or the sound goes through a mono speaker. |
| One button is silent | One side is muted, disconnected or broken: see troubleshooting below. |
| One side is quieter | The balance slider is off center, or one driver is weak or damaged. |
Center plays the same beep on both sides at equal level, about 3 dB below a single side, so the total power stays the same. On a correctly set up pair of speakers it seems to come from a point between them, straight ahead. If the center image leans to one side, check your seating position and the balance setting.
No sound, or sound from one side only? Troubleshooting
When a test is silent, the L and R level meters next to the Volume slider tell you whether the page is sending sound. If the meters move but you hear nothing, the problem is after the browser: in your settings, cables or speakers.
- Wrong output. Open your device's sound settings and check which output is selected. Headphones, a monitor with speakers, a TV and wireless earbuds all appear as separate outputs, and the sound goes to only one of them.
- Muted somewhere. Check the system volume, the volume buttons on the speakers or headphones, and whether the browser tab itself is muted.
- Balance off center. Most systems have a left/right balance slider in the output device's settings. Set it to the middle.
- Mono audio is on. This accessibility setting sends the same sound to both ears, so Left and Right sound identical. Turn it off to test the channels.
- Plug or cable. Push the plug all the way in and wiggle it gently: crackling or dropouts point to a worn jack or cable. A mono plug or adapter in a stereo jack often gives sound on one side only.
- Wireless earbuds. Make sure both earbuds are connected and charged, and that they are not still paired with another phone or computer.
- Phones. Turn up the media volume, not just the ringer. On some phones the ring/silent switch also mutes web page audio.
If one side stays silent on a second device too, the fault is in that speaker, earpiece or cable rather than in your settings.
Phase test: in phase vs out of phase
Speakers are in phase when both cones push out at the same moment. If the + and − wires of one speaker are swapped, that cone moves in while the other moves out, and the pair is out of phase (reversed polarity). The low frequencies, whose wavelengths are long, then partly cancel in the room.
The Phase tab plays pink noise, or an 80 Hz bass tone, on both sides. In phase sends the identical signal to both; Out of phase turns the right side upside down. In phase should sound solid, centered and full. Out of phase sounds wide, vague, as if inside your head on headphones, and noticeably thinner in the bass. Switch every 3 s alternates the two so you can compare. If the version labeled out of phase actually sounds better on your speakers, one of them is wired backwards: check the red and black terminals at both ends of each cable.
Bass and subwoofer test
The Bass tab plays pure sine tones from 20 to 150 Hz and a 20 to 200 Hz sweep that takes 30 seconds. Use them to find the lowest note your system plays, to check that a subwoofer is working, and to hunt down rattles. Keep the volume low: at the same loudness setting, deep tones move a speaker cone much further than higher ones.
| Tones | Range | What to listen for |
|---|---|---|
| 20 to 30 Hz | The lowest bass, at the bottom of human hearing | Felt as much as heard. Only large speakers and capable subwoofers play it; silence here is normal for small speakers. |
| 35 to 60 Hz | Deep bass | The lowest note of a standard four-string bass guitar, E1, is 41.2 Hz. A working subwoofer should play this range clearly. |
| 70 to 120 Hz | Upper bass | Where a subwoofer usually hands over to the main speakers. Listen for a smooth level as you step through the tones. |
| 150 Hz and up | Low midrange | Main speakers and headphones should play these cleanly, without buzzing. |
For reference, the lowest key on a standard 88-key piano, A0, is 27.5 Hz. Some tones will sound louder than others even on a perfect speaker, because the room itself boosts and cancels particular bass frequencies. Move your head or your seat: a dip that moves is the room, while a buzz or rattle that stays put is in the speaker, its cabinet, or something loose nearby.
Frequency sweep and the human hearing range
The Sweep tab glides a sine tone from one frequency to another. It is logarithmic: it moves by equal musical steps, so every octave and every decade takes the same time. In the default 20-second sweep from 20 Hz to 20 kHz, the tone passes 200 Hz after about 6.7 seconds and 2,000 Hz after about 13.3 seconds, and halfway through, at 10 seconds, it is at 632 Hz, the geometric middle of the range. The big readout shows the frequency playing at that moment, computed with the same formula the browser uses to move the tone.
Press Mark this frequency when the tone first appears or fades out, and the page keeps a list of the marks. Repeat the sweep with Left only and Right only to compare the two sides.
Humans can detect sounds from about 20 Hz to 20 kHz. Infants can hear slightly higher; the upper limit falls with age, and in average adults it is often closer to 15 to 17 kHz (Purves et al., Neuroscience). So if the top of the sweep goes silent before 20 kHz, that is normal, and it may be your speakers rather than your ears: many small speakers and earbuds roll off well before the top of the range. The result also depends on the volume and the room. This tool is not a hearing test and cannot diagnose hearing loss. If you notice ringing, muffled hearing or a change in your hearing, see a doctor or an audiologist.
Tone generator and noise: waveforms and colors
The Tone tab is a tone generator from 10 Hz to 22,000 Hz. Type a frequency (440, 1k and 2.5 kHz all work), drag the logarithmic slider, step by 1 Hz or an octave, or pick a preset, and change the frequency, waveform or channel while the tone plays. The note readout names the nearest musical note, with A4 at 440 Hz, the standard tuning pitch set by ISO 16: 1,000 Hz, for example, is B5 · +21 cents.
The four waveforms have very different power at the same peak level, so the tool scales each one to the same average power (RMS) as a sine. Switching waveform therefore does not jump in loudness, although square and sawtooth waves still sound harsher because of their harmonics.
| Waveform | Sound | RMS at peak 1 | Gain applied |
|---|---|---|---|
| Sine | Pure, one frequency only | 0.707 | 1 |
| Square | Hollow and buzzy (odd harmonics) | 1 | 0.707 |
| Sawtooth | Bright and brassy (all harmonics) | 0.577 | 1.225 |
| Triangle | Soft, close to a sine | 0.577 | 1.225 |
The Noise tab plays three kinds of random noise, generated fresh on your device and looped without a seam. They differ in how their power is spread across frequencies:
| Noise | Power per hertz | Sounds like | Good for |
|---|---|---|---|
| White | Flat (0 dB per octave) | Bright hiss | Checking tweeters and high-frequency output |
| Pink | −3 dB per octave | Even, like steady rain | Comparing speakers and channels: every octave has equal power |
| Brown | −6 dB per octave | Deep rumble, like distant surf | Hearing low-frequency output without a single tone |
Surround sound test (5.1 and 7.1)
A web page can only use the output channels the browser gives it. The Surround tab asks how many there are, through the Web Audio API's maxChannelCount, and shows the answer. If it is more than two, you get one button per channel and a Play each in turn option. If it is two, the page says so instead of pretending: some browsers mix everything to stereo, even on a surround system, and the number can change with the output device you select.
Channel names follow the order the Web Audio specification defines. For six channels (5.1) and eight channels (7.1) that is:
| Channel | 5.1 | 7.1 |
|---|---|---|
| 1 | Front left | Front left |
| 2 | Front right | Front right |
| 3 | Center | Center |
| 4 | Subwoofer (LFE) | Subwoofer (LFE) |
| 5 | Surround left | Rear left |
| 6 | Surround right | Rear right |
| 7 | — | Side left |
| 8 | — | Side right |
The subwoofer (LFE, low-frequency effects) channel beeps at 50 Hz, because a subwoofer plays only bass; the other channels beep at 600 Hz. The 7.1 names assume a standard 7.1 layout. If your browser reports two channels, the receiver's own test tones are the reliable way to check each surround speaker.
Volume and hearing safety
Start quiet. Steady test tones can sound louder than music at the same setting, and the highest and lowest frequencies are easy to underestimate because your ears are less sensitive to them, while your speakers still work hard. Raise the volume slowly and stop if anything distorts, rattles or feels uncomfortable.
The page helps: the Volume slider starts at 30%, every sound fades in, and nothing plays until you press a button. But the page cannot know how loud your system volume is, or how efficient your speakers or headphones are, so the real loudness in your ears is up to your device settings.
Health agencies agree on the same principle: how much sound harms depends on both level and time. The U.S. National Institute on Deafness and Other Communication Disorders (NIDCD) says sounds at or below 70 dBA, even after long exposure, are unlikely to cause hearing loss, but long or repeated exposure at or above 85 dBA can. Normal conversation is about 60 to 70 dBA, and music through headphones at maximum volume can reach 94 to 110 dBA. The World Health Organization advises keeping personal audio at no more than 60% of maximum volume, and says adults can safely listen at 80 dB for up to 40 hours a week; at 90 dB that drops to 4 hours a week. For workplaces, NIOSH recommends a limit of 85 dBA averaged over 8 hours, and half the time for every 3 dB more:
| Sound level | NIOSH recommended limit per day |
|---|---|
| 85 dBA | 8 hours |
| 88 dBA | 4 hours |
| 91 dBA | 2 hours |
| 94 dBA | 1 hour |
| 97 dBA | 30 minutes |
| 100 dBA | 15 minutes |
This page cannot measure decibels in your room; the dBFS figure next to the slider is a digital level, explained below. Treat the figures above as general guidance, not a measurement of your listening. This is an educational tool, not medical advice.
How this speaker test works
Every sound is synthesized live by the Web Audio API, the W3C standard for audio in web pages. There are no audio files: tones come from oscillators, and the noise and beep patterns are calculated on your device when you first press play. The audio engine starts only when you press a button, because browsers do not allow pages to play sound on their own, and this page would not want to.
- Left, right and center use a stereo panner with the equal-power law from the Web Audio specification: with x = (pan + 1) ÷ 2, the left gain is cos(x × 90°) and the right gain is sin(x × 90°). Center (pan 0) gives each side 0.707, which is −3 dB.
- The phase test feeds one signal to both outputs, the right side through a gain of +1 or −1.
- The sweep follows f(t) = f₀ × (f₁ ÷ f₀)t ÷ T, the curve of the API's exponential ramp, where f₀ and f₁ are the start and end frequencies and T is the duration.
- Pink noise uses Paul Kellet's refined filter, accurate to within ±0.05 dB; brown noise integrates white noise with a gentle leak, so it falls 6 dB per octave above 20 Hz without drifting.
- The Volume slider is logarithmic, like a real volume knob. At 100% a sine tone peaks at −6 dBFS, half of digital full scale, which leaves headroom; each 10% step lowers it by 4 dB, and 0% is silent.
| Volume | 100% | 75% | 50% | 30% | 10% | 1% |
|---|---|---|---|---|---|---|
| Peak level of a sine | −6 dBFS | −16 dBFS | −26 dBFS | −34 dBFS | −42 dBFS | −46 dBFS |
dBFS means decibels relative to full scale, the loudest sample a digital system can play. It describes the signal the page sends, not the loudness in your room, which depends on your system volume and speakers. The level meters show the same thing for the left and right outputs.
Private by design. The page makes no network requests while you use it, and its Content-Security-Policy only allows connections back to this site. It turns the microphone off through its Permissions-Policy, so it could not listen even if it tried. Your volume and tool settings are kept in your browser's local storage, on your device only.
Frequently asked questions
How do I test my speakers online?
Turn your volume down, then press Left, Center and Right on this page. Each should come from the matching side. Then run the 20 Hz to 20 kHz sweep and the bass tones to hear how wide a range your speakers play, and the phase test to check the wiring. Everything is generated in your browser, so there is nothing to install.
How do I know if my left and right speakers are the right way round?
Press Left: the beeps must come only from the speaker on your left, or your left ear in headphones. If they come from the right, the speakers, their cables or the headphones are swapped. If they come from both sides equally, a mono audio setting is probably on in your device's accessibility settings.
Why does sound only come out of one side?
The usual causes are a balance slider moved to one side in your sound settings, a plug that is not pushed all the way in, a mono plug or adapter in a stereo jack, a damaged cable, or one wireless earbud that is not connected. Run the Left and Right test after each fix. If one side stays silent with another device too, the speaker or earpiece itself is faulty.
What frequency should I use to test a subwoofer?
Start with 40 to 80 Hz at low volume, then try 30, 25 and 20 Hz to find where the output fades. The 20 to 200 Hz bass sweep shows the whole range in 30 seconds. Listen for rattles and buzzes as well as level: a noise that stays put when you move is in the speaker or something near it.
What is the human hearing range?
Humans can detect sounds from about 20 Hz to 20 kHz. Infants can hear slightly higher, and the upper limit drops with age: in average adults it is often closer to 15 to 17 kHz. If the sweep fades out before 20 kHz, that is normal and may be your speakers as much as your ears. This page is not a hearing test.
What does out of phase mean?
Two speakers are out of phase when one cone moves out while the other moves in, usually because the + and − wires of one speaker are swapped. The sound then seems wide and hollow, and bass cancels. The Phase tab plays both versions: in phase should sound solid and centered.
What is the difference between white, pink and brown noise?
White noise has equal power at every frequency, so it sounds bright and hissy. Pink noise loses 3 dB per octave, which gives every octave the same power and sounds more balanced; it is the usual signal for comparing speakers. Brown noise loses 6 dB per octave and sounds like a deep rumble.
Can test tones damage my speakers or my hearing?
At high volume, yes. Steady tones put more strain on speakers than music, especially deep bass and very high frequencies, and loud sound damages hearing over time. NIDCD says long or repeated exposure at or above 85 dBA can cause hearing loss. Start quiet, raise the volume slowly, and stop if anything distorts or feels uncomfortable.
Can I test 5.1 or 7.1 surround sound in a browser?
Only if your browser exposes more than two output channels. The Surround tab asks it how many it has and, if it reports 6 or 8, lets you play each speaker on its own. Some browsers report only 2 even on surround hardware; then use your receiver's built-in test tones instead.
Why is there no sound on my phone?
Check the media volume, not just the ringer, and whether headphones or a wireless speaker are still connected. On some phones the ring/silent switch also mutes web page audio; this page asks the browser to treat its sound as media playback, which avoids that where the browser supports it.
Sources
- W3C, Web Audio API 1.1, Working Draft (22 September 2026): §4.2 channel ordering, §6.3.3 StereoPannerNode panning, AudioParam exponentialRampToValueAtTime and setTargetAtTime, AudioDestinationNode maxChannelCount, ChannelMergerNode.
- MDN Web Docs: Basic concepts behind the Web Audio API (standard channel layouts), maxChannelCount and AudioSession.type.
- Purves D. et al., Neuroscience, 2nd edition (2001), “The Audible Spectrum”, NCBI Bookshelf: the 20 Hz to 20 kHz range and the 15 to 17 kHz adult upper limit.
- NIDCD (National Institutes of Health), Noise-Induced Hearing Loss, updated 16 April 2025.
- World Health Organization, Deafness and hearing loss: Safe listening, 6 March 2026, and Safe listening devices and systems: a WHO-ITU standard.
- NIOSH (CDC), Noise and Hearing Loss: the 85 dBA recommended exposure limit and the 3 dB exchange rate.
- ISO 16:1975, Acoustics: Standard tuning frequency (Standard musical pitch), A4 = 440 Hz.
- Robin Whittle, DSP generation of pink noise, which documents Paul Kellet's refined pink noise filter.
This speaker test is an educational tool, not medical advice, and it is not a hearing test. For any concern about your hearing, talk to a doctor or an audiologist.