Online Tone Generator

20 to 20,000 Hz

20%

Start at a low volume, especially when using headphones.

440 HzFrequency
2.273 msWave period
A4Nearest equal-tempered note
StoppedPlayback state

Generate a continuous or timed test tone from 20 Hz to 20 kHz. Choose a waveform, set a safe volume, or use common frequency presets.

The tone is produced by the Web Audio API and never leaves the browser. Gain ramps are used when starting and stopping to reduce audible clicks.

Frequency and waveform

Sine waves contain one frequency, while square, triangle, and sawtooth waves include additional harmonics and sound brighter. The nearest musical note is an approximation based on A4 at 440 Hz.

Hearing safety

Begin with the volume low and stop immediately if a tone is uncomfortable. Headphones can produce high sound pressure even when the browser volume appears modest. Very low and very high frequencies may be inaudible but can still drive speakers.

Related audio tools: Metronome · Tone Generator · BPM Tapper · Voice Recorder