Audio Signal Generator Online — Free Browser Function Generator
A free, browser-based audio signal generator for engineers, audio professionals, students, and audiophiles. Function-generator capability — without the function-generator price tag.
What is an Audio Signal Generator?
An audio signal generator (also called a function generator) is a tool that produces calibrated test signals at known frequencies and waveforms. Engineers use them to verify amplifier response, test cables, measure speaker performance, calibrate level meters, debug audio circuits, and align tape heads.
Traditional bench function generators cost hundreds of dollars. Ours runs free in your browser — same audio-range capability, same 1 Hz precision, same clean waveforms, just without the rack space.
Features
Full Audio Range
20 Hz – 20 kHz coverage, 1 Hz steps, with all four canonical waveforms.
Pure Output
Web Audio API generates mathematically clean signals — perfect for measurement.
Engineering Presets
Mains 50/60 Hz, 400 Hz avionics, 1 kHz reference, 10 kHz response — all one tap.
Sample-Accurate
Frequency adjustments are sample-accurate with no audible discontinuities.
Portable Bench
Carry a full signal generator in your phone for field measurement.
Output Protection
Smooth fade prevents driver damage when starting/stopping high-amplitude signals.
Common Uses
Feed a known signal in, measure THD, IMD, and frequency response at the output.
1 kHz reference tone reveals bad cables, intermittent contacts, and hum loops.
Measure pink noise or sweep response against a calibrated reference SPL.
Demonstrate harmonics, beats, and waveform synthesis to students live.
How to Use
1. Choose Waveform
Pick sine, square, sawtooth, or triangle depending on the tone character you need.
2. Set Frequency
Use the slider or tap a preset to dial the exact frequency you need.
3. Adjust Volume
Start at low volume — pure tones can be louder than they feel.
4. Press Play
Hit Play and the tone keeps playing continuously until stopped.
Frequently Asked Questions
For audio-range work, yes — the Web Audio API uses double-precision floating point internally and is limited only by your soundcard's clock accuracy (typically <50 ppm).
Currently the tool generates continuous tones. For noise, see our white noise generator. For sweeps, drag the slider manually.
Output amplitude scales linearly with the volume slider. 100% volume corresponds roughly to full-scale digital output — verify with an actual meter for absolute measurements.
Yes — use a TRS or 1/8" cable from your device's headphone jack to your gear input. Match impedance and level as needed.
The Web Audio API outputs centred audio signals with zero DC offset, exactly as expected from clean audio gear.
Hearing Safety
Pure tones — especially below 40 Hz or above 10 kHz — carry significant energy at high volumes. Start low and protect your hearing and speakers.