Tone Generator
Online Tone Generator
Play any frequency (Hz) and waveform right in your browser — a free online frequency generator for testing speakers, hearing and instruments.
440Hz
20 Hz20 kHz
⚠️ Start at a low volume to protect your ears and speakers.
How to use the tone generator
Drag the slider or tap a preset to set a frequency, choose a waveform, then press Play. The sine wave is a pure tone ideal for speaker and hearing tests; switch to square, sawtooth or triangle for richer, harmonic-heavy sounds. This online frequency generator covers the full audible range, 20 Hz to 20,000 Hz.
Want to know the note of a frequency, or the frequency of a note? Try the pitch detector. To check your full system end to end, run the sound test.