Tone Generator
Play any frequency from 20 Hz to 20 kHz. Start quiet: tones can be louder than they seem.
Hz
A4Type a number, or 1k for 1000
Keep headphones at a low volume. Loud pure tones can damage hearing.
Presets
How to use the tone generator
- Set the frequency. Type it in the box, drag the slider or pick a preset. The slider is logarithmic, so 20 to 200 Hz gets as much room as 2 to 20 kHz.
- Press Play. The tone fades in. Change the frequency while it plays and it glides there without clicks.
- Fine-tune with -1 Hz and +1 Hz, or jump an octave with Octave up and Octave down. The display shows the nearest musical note and how many cents it is off.
What people use a tone generator for
- Testing speakers and subwoofers: find the lowest frequency your speakers can play, or a rattle that only happens at one pitch.
- Tuning instruments: play A4 at 440 Hz and tune until the slow wobble (beating) between tone and string disappears.
- Finding a hum: mains hum is 50 Hz in Europe and most of the world and 60 Hz in North America. Play both to see which matches a buzz in your audio setup.
- Tinnitus matching: some people use a tone to describe the pitch of their tinnitus to a doctor. Keep the volume very low.
- Science and electronics: demonstrate pitch, resonance or the difference between waveforms, or feed a known signal into a circuit.
Waveforms
A sine wave is a single pure frequency. Triangle adds a few soft odd harmonics. Square and sawtooth are rich in harmonics and sound buzzy, so they seem much louder at the same level; this generator turns them down automatically to keep the volume even.
Questions and answers
How do I play a specific frequency?
Type the frequency in the box (for example 440, 1k or 12500) and press Play. You can also drag the slider, which is logarithmic so every octave gets the same space.
What are sine, square, sawtooth and triangle waves?
A sine wave is a pure tone with a single frequency. Square and sawtooth waves add many overtones and sound buzzy and bright; triangle sits in between. Use sine for hearing and speaker tests and the others for synth or electronics work.
What is 440 Hz?
440 Hz is the note A above middle C (A4), the standard tuning pitch for most Western music.
Can a tone generator damage my hearing or speakers?
Yes, if it is loud. Pure tones are tiring and high frequencies can be louder than they seem. Start with the volume low, raise it slowly, and never play loud tones through headphones.
Can I use it to tune an instrument?
Yes. Pick the reference note, for example A4 at 440 Hz, and tune until the beating between the tone and your instrument disappears. The display shows the nearest note name for any frequency.