Why can't I hear anything at 20 Hz?

20 Hz is the theoretical lower limit of human hearing and requires speakers with strong bass response (like subwoofers). Most laptop and phone speakers cannot reproduce frequencies below ~80 Hz.

Is it safe to use at high volumes?

Keep the volume low, especially above 4 kHz. High-frequency tones at high volume can be painful and may cause temporary or permanent hearing damage.

What's the difference between the waveforms?

Sine: pure, smooth. Square: rich in odd harmonics, sounds hollow. Triangle: smoother than square, similar to sine but slightly brighter. Sawtooth: all harmonics, sounds buzzy — great for stress-testing speakers.

Why does the Play button not work immediately?

Browsers require a user gesture before they allow audio playback. The AudioContext is created and started on your first click to comply with this browser policy.

Sound Tester

Test your speakers or headphones with tones, a bass sweep, a left/right stereo check, and a distortion test.

Turn your system volume down before you start — test tones can be much louder than music, and bass sweeps at high level can damage small speakers.

Play a pure tone at any frequency to check the full range of your speakers or headphones.

Quick test frequencies

Custom frequency: 440 Hz

Waveform

Volume: 30%

Output level—

Press Play to start the test

What is Sound Tester?

Sound Tester runs four speaker checks through your browser's Web Audio API: a pure tone generator across the full audible range, a sub-bass test with an automatic 20–120 Hz sweep, a left/right stereo check, and a volume ramp that reveals the level at which your speakers start to distort — all without installing any software.

How to Use Sound Tester

Turn your system volume down first, then pick a test tab: Tone, Bass, Stereo, or Volume & distortion.
Tone: choose a preset frequency (20 Hz – 16 kHz) or drag the slider, and pick a waveform — Sine (pure), Square (hollow), Triangle (mellow), or Sawtooth (bright).
Bass: pick a frequency between 20 and 200 Hz, or switch on the sweep to roll continuously from 20 Hz up to 120 Hz.
Stereo: play Left only, Right only, or Both — or enable auto-swap to hop between channels every 1.5 seconds and confirm nothing is wired backwards.
Volume & distortion: pick a tone or white noise, enable the level ramp, and stop as soon as the sound turns gritty or buzzy — that is where your speakers clip.
Click Play to start and Stop to end; the output level meter shows the signal your browser is sending.

Examples

Bass response check

Input: 20 Hz – 100 Hz, sine wave, medium volume

Output: Deep rumble — inaudible on laptop speakers, audible on subwoofers

High-frequency hearing test

Input: 8 kHz – 16 kHz, sine wave, low volume

Output: Younger listeners can typically hear 16 kHz; hearing loss often shows first here

Speaker distortion test

Input: 1 kHz sine wave, increasing volume

Output: Crackling or buzzing at high volume indicates driver distortion

Common Mistakes

Starting with volume too high — always start low and raise gradually, especially with unfamiliar frequencies.
Testing over Bluetooth — Bluetooth codecs compress audio and may affect perceived frequency response; use a wired connection for accurate results.
Expecting to hear all frequencies — human hearing spans roughly 20 Hz to 20 kHz, and this range narrows with age; not hearing a very high frequency isn't always a speaker problem.

Why Use This Tool

No installation needed — runs directly in your browser using the Web Audio API.
Four tests in one tool: tone, bass, stereo channels, and volume/distortion.
Full audible frequency range from 20 Hz to 20 kHz, plus a dedicated 20–120 Hz bass sweep.
Left/right channel test with auto-swap catches a dead speaker or reversed wiring in seconds.
Live output level meter with a dBFS readout while any test plays.
Multiple waveforms and white noise to stress-test different aspects of speaker performance.
Entirely private — no audio data is ever sent to a server.