Web Audio Instrument

The Frequency Generator

Any tone from 1 Hz to 22 kHz — plus sweeps, stereo pairs, binaural beats, and a WAV to take home. All in your browser, nothing installed, nothing uploaded.

Fig. 1 — signal source ● LIVE
Hz
1101001k10k22k

Two independent oscillators, hard-panned. Handy for stereo wiring checks and “is the left driver actually dead?” questions.

Left ear / channel

Right ear / channel

Slightly different tone in each ear; your brain invents the difference as a slow pulse. Headphones required — through speakers it's just two tones arguing.

Base frequency

Beat frequency

Now passing: —. Log curve spends equal time per octave — that's how your ears think, so use it unless you have a reason not to.

Three colors of random. White has equal energy at every frequency — hissy, great for masking and speaker torture. Pink drops 3 dB per octave, which is roughly what rain does; it's the mixing-room reference. Brown keeps falling — rumble, ocean-ish, the gentle one.

Export works here too — a looping WAV of pink noise is a legitimately useful thing to own.

30%
Loud + high-pitched is the combination that damages hearing. Take it down a notch — the tone is just as measurable at 30%.

Jobs people came here to do

Your presets

    Speaker reality check — can your hardware even play this?

    We play short tones from 8 to 22 kHz through your speaker and listen with your mic. If a tone registers, your whole chain — speaker and mic — genuinely reproduced it. If it doesn't, the generator isn't lying; your hardware is just done. (Nothing is recorded; the mic feeds a live meter and stops.)

    8k10k12k14k15k16k17k18k19k20k21k22k

    Space play/stop · ↑↓ ±1 Hz · Shift+↑↓ ±100 Hz · O octave up, Shift+O down

    What's in the box

    Exact to the decimal

    Type 439.6 and you get 439.6. The slider is logarithmic (like your ears); the number field is for when you mean business.

    Four waveforms + three noises

    Sine for testing, square and sawtooth for character, triangle in between — plus white, pink and brown noise for masking, mixing and sleep. Changes apply live.

    Sweeps that loop

    20 Hz to 20 kHz over any duration, linear or logarithmic, looping if you like. Watch the live readout ride the curve.

    Stereo, properly

    Independent left/right frequencies with per-channel mute, plus a dedicated binaural mode that does the ear-math for you.

    Take the tone home

    Export exactly what you configured as a 16-bit stereo WAV — tone, sweep, or binaural pair — rendered on your device.

    Links that remember

    Settings live in the URL. Send someone a link and their generator opens dialed to your exact tone.

    Three honest facts before you trust any tone

    1. Browsers require a tap before audio. Nothing plays until you press Play — that's an autoplay rule, not a bug.

    2. Your speaker has opinions. Most phone and laptop speakers give up somewhere between 18 and 20 kHz, and below ~80 Hz they mostly emit wishful thinking. The generator outputs the correct signal; the hardware decides what survives. That's exactly why the speaker reality check exists — no other tone generator will tell you this.

    3. Loud + high = harm. Sustained high-frequency tones at high volume can damage hearing you won't get back. The tool warns you at the risky combination; please believe it.

    Questions people actually ask

    Is this frequency generator free?

    Free, no account, no watermark, no "pro tier". It's JavaScript in your browser — there's no server bill to pass along to you.

    What range can it generate?

    1 Hz to 22 kHz with exact numeric entry. Whether you can hear the extremes is a separate question — adults typically lose everything above ~16–17 kHz, and speakers roll off too. Run the speaker check for the honest answer on your device.

    Can I download the tone?

    Yes — Export WAV renders your current settings (tone, sweep, dual, or binaural) to a 16-bit stereo file, generated locally.

    Do binaural beats need headphones?

    Yes. Each ear must get its own frequency for the effect to exist. Through speakers the tones mix in the air and you just hear plain old beating.

    Why can't I hear anything above 17 kHz?

    Age, most likely, or your speaker quit first. The speaker check tells you which one to blame.

    Does it work offline?

    Yes — install it (Add to Home Screen) and it runs with no connection after the first load.

    From the notebook

    Explainer

    What is a frequency generator actually used for?

    Speaker tests, tinnitus matching, physics homework, and one use that definitely doesn't work.

     Ear training

    Sine vs square vs triangle vs sawtooth

    Why a square wave at the same pitch sounds angrier — harmonics, explained by listening.

     How-to

    Test your speakers' frequency range at home

    Ten minutes, no equipment, and you'll know exactly where your speakers give up.

     Skeptical

    Binaural beats: what the science actually says

    Less than the YouTube titles claim, more than nothing. The honest read.

    Related tools

    On this site

    Hearing range test

    Step from 8 to 20 kHz and find your personal ceiling. Two minutes, ego optional.

     On this site

    Dog whistle

    The 15–22 kHz end of this tool, dressed for dog owners — with the honesty others skip.

     On this site

    Spectrum analyzer

    See every frequency in a sound, live from the mic, peak labeled in Hz.

     Sibling site

    Pitch detector

    The other direction: it listens and names the note to ±1 cent. Handy for checking this generator.