Tone Generator
Make a test tone: 440 Hz, 1 kHz or any frequency, played live or saved as a file. It starts quiet.
Protect your hearing
Square and sawtooth waves are band-limited in the exported file, so they do not alias.
Nearest note: A4
The address always holds the frequency and the waveform.
The highest point of the wave, relative to digital full scale.
Up to 12 hours. Long files are written in pieces, so length costs time, not memory.
Fades start and end the file smoothly, so it does not click. Keep at least a few milliseconds.
How it works
- Choose the waveform and type a frequency.
- Set the level; it defaults to a safe, quiet value.
- Press Play to hear it.
- Set a duration and download it as WAV, MP3 or FLAC.
What it does
The tool makes a steady tone of one frequency. Choose a sine, square, triangle or sawtooth wave, set any frequency from 1 Hz to 22 kHz with the slider, the number box, a note name or the octave and 1 Hz buttons, and press Play to hear it. When it sounds right, set a length and save it as a file in WAV, MP3, FLAC and other formats.
The address of the page always holds the frequency and the waveform, for example ?f=440&w=sine, so you can copy the link and send a particular tone to someone.
Waveforms and quality
A sine wave is a single pure frequency. Square, triangle and sawtooth waves add harmonics above it, which makes them brighter and more buzzy. Naive square and sawtooth waves produce aliasing, harsh extra tones below the main one; the exported file uses a band-limited version, so a square or sawtooth at 5 kHz stays clean. Live playback uses your browser’s own oscillator, which is band-limited as well.
Set the fade in and fade out so the file starts and ends smoothly. A tone that begins at full level mid-wave clicks.
Safe levels
The level is in dBFS, decibels below digital full scale, and starts at −18 dBFS. What you hear depends on your volume control, speakers and headphones, so start with the device volume low. Levels above −6 dBFS ask for confirmation, and very low or very high frequencies can be hard on speakers and ears even when they do not sound loud.
The note picker uses equal temperament with A4 at 440 Hz; change the reference to match an instrument tuned to something else.
Questions
How do I make a 440 Hz or 1 kHz test tone?
Type 440 or 1000 into the frequency box, keep the waveform on sine, set the length and choose Create file. The preset buttons under the slider jump to common values.
Why does the tone stop when I change the frequency?
It does not: live playback follows the slider and glides to the new frequency. If you hear it stop, press Play again.
Can I make a very long file?
Yes, up to 12 hours. The tone is generated in pieces while it is written, so the length costs time rather than memory. Very long WAV files are large; MP3 or FLAC make them smaller.
Is the tone safe to play at full level?
Treat any steady tone with care. Start with the device volume low, keep the level near the default, and avoid long listening at high volume or on headphones.