About Tone Generator
Tone Generator creates a pure audio tone at a frequency and duration you specify, in one of four waveforms, and delivers it as a downloadable WAV file. Set the frequency in hertz, choose how many seconds it should last, pick sine, square, sawtooth or triangle, and run the tool to get a playable file.
The output is a standard uncompressed WAV — a 44.1 kilohertz sampling rate, 16-bit samples, single channel — so it plays in the page and opens in any audio editor without conversion. The sine wave is a clean single frequency with no harmonics, which makes it the right choice for testing speakers, tuning an instrument or checking a hearing range. The square, sawtooth and triangle waves are progressively richer in harmonics, useful when you want a brighter, more electronic timbre or a signal for testing a filter.
A few properties are fixed by design, and they matter if you expect a synthesiser. The level is constant at about half the maximum amplitude with no fade in or out, so the very start and end can produce a small click in some players; fading or trimming in an editor removes it. There is no stereo, no volume control and no envelope — this is a signal generator.
The parameters also stop short of what tone generation often calls for. Only one tone is produced per run, so no chord, interval or two-tone beat can be generated, and there is no option to sweep a frequency across a range — the pitch is held constant for the whole duration. Amplitude, sample rate and bit depth are all fixed, so no dB-scaled level, no higher or lower sample rate and no quieter export can be requested, and the same is true of the format: the file is always WAV, with no MP3 or OGG alternative and no choice of stereo width or panning. There is no noise floor, no modulation such as vibrato or tremolo, no sequence of tones, and no preview of the waveform shape before you download the result.
How to use Tone Generator
- 1 Enter the frequency in hertz — 440 gives the standard A above middle C.
- 2 Set the duration in seconds, up to thirty.
- 3 Choose a waveform, run the tool, then play or download the generated WAV.
Frequently asked questions
What audio format is produced?
An uncompressed WAV file at 44.1 kHz, 16-bit, in a single channel. It is a standard format, so it plays directly in the page and opens in any audio editor with no conversion step.
Why can I hear a click at the start and the end?
Because the tone begins and ends at full amplitude with no fade. A sudden start or stop is a step in the waveform, which the ear hears as a click. Trimming a few milliseconds in an editor, or applying a short fade, removes it.
What is the difference between the four waveforms?
A sine wave contains only the fundamental frequency, so it sounds pure. Square, sawtooth and triangle waves add harmonics in different proportions, giving a brighter, more complex tone. Sine is best for calibration; the others suit testing or a harsher sound.
Can I generate frequencies outside 20 Hz to 20 kHz?
The fields are bounded to that range because it matches the nominal limits of human hearing. Lower frequencies are felt rather than heard on most speakers and higher ones are inaudible to many adults, so the limits keep the output useful.
Can I make a stereo file or two tones at once?
No. The generator produces a single channel containing one frequency. To put a different frequency in each ear you would want a binaural beat generator, which is a separate tool.
Free, online, and private
Free to use
Tone Generator is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.
How Tone Generator behaves in detail
These are the specifics of this implementation — the exact ranges, defaults and fixed settings you are working with.
| Parameter | Value |
|---|---|
| Output | a data:audio/wav;base64 URL holding 16-bit PCM, one channel, 44,100 Hz, behind a hand-written 44-byte RIFF header |
| Waveforms | 4 — sine, square, sawtooth and triangle, defaulting to sine |
| Frequency input bounds | 20 – 20,000 Hz, default 440 |
| Duration input bounds | 0.1 – 30 seconds, default 2 |
| Level | every waveform is scaled to 0.5 of full scale, roughly −6 dBFS, and that is the only gain in the chain |
| Longest output | 30 s at 44,100 Hz mono 16-bit is 2,646,000 PCM bytes — about 3.5 MB once base64-encoded |
Compiled from the implementation of this tool and checked against it by itoolnet.
What Tone Generator does not do
Knowing the edges of a tool saves more time than another list of its features. These are the cases where it will not do what you might expect.
- There is no envelope and no fade. The sample loop begins and ends at full amplitude, so every tone clicks at both boundaries, and with no attack or release parameter on the form there is no way to soften that from the interface.
- Level is fixed. The only gain anywhere is the hard-coded 0.5 multiplier, so neither a quieter nor a louder result can be requested, and there is no normalise, no limiter and no way to superimpose the tone on anything else.
- Square, sawtooth and triangle are the ideal mathematical shapes with no band-limiting. Sample values are computed straight from the waveform formula at 44,100 Hz, so harmonics above the Nyquist frequency fold back as audible tones instead of being filtered out.
- The entire waveform is materialised before it is offered. One Float32Array is allocated for the whole duration and then a base64 string is concatenated in 32,768-byte chunks, which is why the duration stops at 30 seconds rather than being open-ended.
Tested and documented by itoolnet, the team that builds and maintains this site.