Online Tone Generator

Runs on your device. Nothing is sent.The sound is made in your browser - nothing is uploaded, and it works offline.

440 Hz⁦A4⁩ · +0 cents

Start quietly: loud or very high tones can hurt your ears and damage small speakers.

Frequency (Hz)

Note

A4 tuning (Hz)

Waveform

Level: ⁦-20 dBFS⁩

Speaker

Keys: Space play/stop · ← → 1 Hz (Shift for 10) · ↑ ↓ a semitone

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Length

The WAV is 16-bit, 48 kHz - mono, or stereo when one speaker is chosen - and is made on your device.

Play any frequency from 1 Hz to 24 kHz as a sine, square, triangle or sawtooth wave, sweep between two frequencies or play white, pink or brown noise.

A tone generator plays a pure tone at exactly the frequency you choose. Type a frequency, drag the slider (each octave gets the same width), jump by octaves or semitones, or pick a musical note with your own A4 tuning. Choose a sine, square, triangle or sawtooth wave, set the level in dBFS and send it to the left, right or both speakers. Sweep mode glides between two frequencies to test speakers and headphones, and noise mode plays white, pink or brown noise. Everything is generated in your browser and can be saved as a WAV file.

Frequently asked questions

What frequencies can people hear?

Roughly 20 Hz to 20 kHz when young; the top end falls with age, and many adults hear little above 14-16 kHz. Very low tones are felt as much as heard. Small phone and laptop speakers can't reproduce much below 100-200 Hz, so use headphones or proper speakers for low tones.

How do I test my speakers or headphones?

Use Left and Right to check each channel is connected the right way round, then play a slow logarithmic sweep from 20 Hz to 20 kHz at a moderate level: listen for where the sound fades in and out, and for buzzing or rattles at particular frequencies. Pink noise is the usual signal for matching the loudness of several speakers.

What's the difference between the waveforms?

A sine is a single pure frequency. Square, triangle and sawtooth add harmonics - multiples of the frequency - so they sound buzzier: a square has only odd harmonics and sounds hollow, a sawtooth has all of them and sounds bright. The browser generates them band-limited, so they don't alias into stray tones.

What does dBFS mean?

Decibels relative to full scale: 0 dBFS is the loudest level a digital signal can reach, and every -6 dB halves the amplitude. The level here is the peak of the wave. -20 dBFS is a safe start; how loud that sounds depends on your device volume.

Can it help with tinnitus or find my tinnitus frequency?

Some people use a tone to match the pitch they hear, by moving the frequency until it sounds the same. That can be useful to describe it to a doctor, but this is not a medical tool - keep the level low and see an audiologist about tinnitus.

Is A4 always 440 Hz?

440 Hz is the international standard concert pitch. Some orchestras tune a little higher (442-443 Hz) and some musicians prefer 432 Hz. Change the A4 tuning and every note in the list follows it, and the display shows how many cents any frequency is from the nearest note.

Online Tone Generator