TidyFigure

Tone Generator

  • 100% free
  • No sign-up
  • Runs in your browser

Press Play and drag the slider, or type an exact frequency in hertz. Choose the wave shape, volume and left/right balance, use the presets (such as 440 Hz for tuning) and step up or down by semitones. Sweep glides from low to high so you can test speakers or find your hearing range.

Hz

Start quietly, especially with headphones.

Now

Press Play to start the tone.

Everything runs in your browser. Nothing you type is sent anywhere.

Uses for a tone generator

  • Tuning: 440 Hz is the A above middle C (A4), the standard tuning pitch.
  • Speaker and headphone tests: check each channel with the balance control, find rattles with a slow sweep, and see how low your subwoofer goes.
  • Hearing range: young people hear roughly 20 Hz to 20,000 Hz; the top limit falls with age (often 12,000–15,000 Hz by middle age).
  • Science and teaching: demonstrate pitch, beats and wave shapes.
  • Room acoustics: find frequencies that boom or vanish in a room.

Wave shapes

  • Sine: a pure tone with a single frequency. Use this for testing.
  • Square: hollow and buzzy, rich in odd harmonics (like old video games).
  • Triangle: softer than square, between a sine and a square.
  • Sawtooth: bright and brassy, with every harmonic.

Frequency guide

RangeWhat it sounds like
20–60 HzSub-bass: felt more than heard
60–250 HzBass: kick drums, mains hum (50 or 60 Hz)
250–2,000 HzMids: most of the human voice
2,000–6,000 HzPresence: where hearing is most sensitive
6,000–20,000 HzTreble and “air”: cymbals, sibilance

Protect your hearing and speakers

Start with the volume low, especially with headphones: pure tones can sound much louder than music at the same setting. Very low and very high frequencies at high volume can also damage small speakers. Your device and speakers limit the range you’ll hear; many laptop speakers produce little below 150 Hz.

Frequently asked questions

What frequency can humans hear?

Roughly 20 Hz to 20,000 Hz for young people. The upper limit falls with age, often to 12,000–15,000 Hz by middle age.

What is 440 Hz?

It’s the note A above middle C (A4), the standard pitch orchestras and instruments tune to.

Why can’t I hear very low or high tones?

Small speakers and laptop speakers can’t reproduce very low bass, and high tones may be beyond your hearing or your headphones’ range.

Can I test left and right speakers?

Yes. Move the balance slider fully left or right to play the tone through one channel only.

Is it safe to listen to test tones?

Yes at a sensible volume. Start low and turn it up slowly, especially with headphones, as pure tones can be surprisingly loud.

Last updated October 2026 · More video & audio tools