Play a pure sine, square, triangle or sawtooth tone from 20 to 20,000 Hz with Web Audio, sweep frequencies, and pan left/right. Starts quiet at 10% volume.
The tone is generated locally with Web Audio in your browser. Nothing ever leaves your device.
Web Audio draws the signal at your sound card instead of playing a file. Pressing Start builds a three-node graph: an OscillatorNode producing the waveform at your frequency, a GainNode applying your volume, and — when the browser supports it — a StereoPannerNode deciding left versus right, all chained into your default output device. Changing a slider does not rebuild anything: frequency, volume and balance are set with the audio-clock-aware setTargetAtTime, so adjustments glide without clicks. The AudioContext itself is created lazily on your first click because browsers only allow audio after a user gesture. This page deliberately stops when you leave it, and it only makes steady tones and sweeps — broadband hiss like white or pink noise is a different tool.
Yes, at high volume low frequencies are the biggest risk: small phone drivers have little excursion, and driving 40-120 Hz near maximum output pushes them past their travel limits, which is where distortion turns into heat in the voice coil. Keep the volume low while testing, especially on the 20 Hz and 60 Hz presets, and turn it down before you start a sweep that passes through the bass.
As a rough demo, yes; as an audiogram, no. Real hearing tests use calibrated equipment measured in dB HL because laptop, phone and headphone output levels all differ by many decibels — so you cannot map your volume slider to any known loudness. Use it to explore what you can hear at 250 Hz versus 8 kHz, but take thresholds to a professional. And keep it gentle: repeatedly hunting your hearing limit at high volume is exactly how noise-induced damage creeps up.
In order: confirm your OS and player output device are the same (browsers follow the system default, which may be a disconnected monitor over HDMI); make sure the browser tab is not muted in your volume mixer; check the volume slider is above 0 — it intentionally starts at 10%; and on a phone, note that silent switches and low-power modes can block audio until you interact with the page again. If the status line says Playing but nothing comes out, the browser is routing elsewhere, not broken here.
No — this page is an oscillator, meaning one steady pitch at a time, plus frequency sweeps. Noise is a different signal family (random energy spread across the spectrum), and this site keeps it in its own tool: see the Noise Machine in the same category for white, pink and brown noise. Squaring the two pages keeps each audio graph simple and honest.
No. The tone is generated by your browser's Web Audio engine — the oscillator, gain and panner all run on your device and the signal never leaves it. There is no recording, no storage, no analytics attached to Start, and the page works offline once loaded.
If you just finished with Tone Generator, the natural next steps are Noise Machine, Dead Pixel Test, Screen Resolution Checker, or browse every tool in Daily Tools.