BrowserTools

Tone Generator

Play sine, square & saw tones at any Hz

By Guga — BrowserTools maintainer, Tbilisi, Georgia Updated 2026-08-10
Free Private No uploads
What is Tone Generator?

One oscillator, one gain stage and one destination. Choose a waveform, drag the frequency between 20 Hz and 20,000 Hz, and press Play. The page names the nearest musical note and shows how many cents sharp or flat you are from it, which is handy when matching a speaker test against a known pitch. Two things to know about the controls: the frequency slider is linear, so the musically useful range below 2 kHz occupies nine tenths of the travel and the top two octaves are squeezed into the last tenth; and the volume control tops out at half scale, which is deliberate headroom but also means you cannot drive the output harder. A tone that produces silence from a laptop speaker is often not missing — it is above what that speaker reproduces.

Generate pure audio tones from 20 Hz to 20 kHz with sine, square, triangle and sawtooth waveforms. Used for speaker testing, hearing checks, and audio experiments.

Private Tone Generator In Your Browser

Tone Generator is processed locally with client-side JavaScript. Your files never touch a server, and there is no queue to wait in.

Step-by-Step

How to use Tone Generator

1

Pick a waveform from the dropdown: sine for a pure reference, square or sawtooth for harmonic-rich alignment work, triangle for a softer buzz.

2

Drag Frequency to the value you want, or click a preset chip such as 440 Hz or the 15 kHz test tone; the note name updates live.

3

Adjust Volume, then press Play tone; the frequency and waveform can be changed while it is already sounding.

4

Press Stop tone when finished — there is no recording step and no file is produced.

Key Capabilities
  • Covers 20 Hz to 20,000 Hz in one hertz step with a note name and cent deviation shown beside the value.
  • Offers sine, square, triangle and sawtooth waveforms that can be switched while the tone is playing.
  • Presents seven preset frequencies including 20 Hz, 440 Hz, 1 kHz, 4.4 kHz and a 15 kHz test tone.
  • Changes frequency and volume live through the audio graph rather than restarting the tone.
Common Use Cases
  • A speaker builder sweeping a sustained tone while listening for rattles and resonances in a cabinet.
  • A sound engineer ringing out a room at 100 Hz and 1 kHz before a recording session.
  • A musician checking whether a monitoring system reproduces a 15 kHz test tone, or comparing two notes by ear.
Clear Answers

Frequently Asked Questions

Why does a high frequency produce no sound at all?
Most likely the hardware. Small laptop and phone speakers roll off steeply above about 10 kHz, so a 15 or 20 kHz tone can be present in the signal and still inaudible through them. Check the meter or try headphones before assuming the generator is at fault.
Is the frequency exact?
The oscillator is driven by the audio hardware's own clock, and that clock is not a laboratory reference. It will be close, and good enough for tuning by ear, but a cheap sound card's tolerance is a larger error than anything this page introduces. Treat the reading as nominal.
Why will the volume not go louder?
The slider maps to a gain of up to 0.5 rather than full scale, which leaves headroom and avoids harsh clipping through an amplifier. That also means the control tops out at half amplitude even on a quiet system; turn up the system volume instead.
Can I save the tone to a file?
No. Nothing is recorded or rendered here — the oscillator feeds the speakers and that is the end of the signal chain. If you need a tone as a file, look for a generator that offers WAV export instead.