What is the reference for the note name?

A4 = 440 Hz, with each semitone = 2^(1/12). The cents value shown is the offset from the nearest semitone. If you prefer the 432 Hz convention (used in some classical and historical contexts) pick the "A4 (432Hz)" preset — the note label will read A4 with about −32 cents.

Do I really need fade in / out?

Yes, it's a good idea. Hard starts and stops can produce a clicking (clipping) noise in speakers and headphones. A 20 ms (0.02 s) fade is enough to eliminate the click without changing the perceived pitch or noticeably distorting the waveform.

Almost certainly not. Typical adult hearing tops out at 15–17 kHz, and most consumer speakers / headphones roll off near 20 kHz. For hearing tests, try 12 / 14 / 16 / 18 kHz in steps to see where you stop hearing the tone.

Square / sawtooth at high frequencies sound strange — why?

Harmonics above the Nyquist frequency (half the sample rate = 22.05 kHz) fold back as aliasing into the audible range. This tool uses simple analytic generation without anti-aliasing (it's optimised for test signal use). Pick sine if you need clean high frequencies.

What WAV format is exported?

Uncompressed mono WAV, 44.1 kHz sample rate, 16-bit little-endian PCM, with a minimal 44-byte RIFF header. It is readable by virtually every DAW and player. Post-process elsewhere if you need stereo / 24-bit.

Back to Audio

Test Tone Generator

Generate test tones at any frequency from 20 Hz to 20 kHz using the Web Audio API. Choose sine / square / triangle / sawtooth, presets like A4 (440 Hz) / 1 kHz / 10 kHz, and see the matching note name and cents offset live. Built-in fade in/out avoids click noise. Download as WAV (44.1 kHz / 16-bit / mono). Useful for instrument tuning, speaker channel checks, hearing tests, and reference signals. Everything is synthesized in your browser — nothing uploaded.

audiogenerate

How to use

Pick a waveform (sine / square / triangle / sawtooth), enter a frequency (Hz) via the number field or slider, then press Play. The Presets row gives one-click access to A4 = 440 Hz / 432 Hz, C4, C5, 1 kHz, 10 kHz. Adjust duration, volume, and fade in / out as needed, then save the tone as a 44.1 kHz / 16-bit mono WAV. For tuning use sine + a longer duration (5–10 s); for speaker or hearing checks use 1 kHz sine + short (1–2 s); for synth timbre comparison hold the frequency fixed and switch between the four waveforms.

FAQ

What is the reference for the note name?: A4 = 440 Hz, with each semitone = 2^(1/12). The cents value shown is the offset from the nearest semitone. If you prefer the 432 Hz convention (used in some classical and historical contexts) pick the "A4 (432Hz)" preset — the note label will read A4 with about −32 cents.
Do I really need fade in / out?: Yes, it's a good idea. Hard starts and stops can produce a clicking (clipping) noise in speakers and headphones. A 20 ms (0.02 s) fade is enough to eliminate the click without changing the perceived pitch or noticeably distorting the waveform.
Can I hear 20 kHz?: Almost certainly not. Typical adult hearing tops out at 15–17 kHz, and most consumer speakers / headphones roll off near 20 kHz. For hearing tests, try 12 / 14 / 16 / 18 kHz in steps to see where you stop hearing the tone.
Square / sawtooth at high frequencies sound strange — why?: Harmonics above the Nyquist frequency (half the sample rate = 22.05 kHz) fold back as aliasing into the audible range. This tool uses simple analytic generation without anti-aliasing (it's optimised for test signal use). Pick sine if you need clean high frequencies.
What WAV format is exported?: Uncompressed mono WAV, 44.1 kHz sample rate, 16-bit little-endian PCM, with a minimal 44-byte RIFF header. It is readable by virtually every DAW and player. Post-process elsewhere if you need stereo / 24-bit.

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