Free Browser Sound Tools
Make sound in your browser with the Web Audio API. No downloads, no signup, no uploads.
🎹 Additive Synthesizer
Build a waveform from up to eight sine partials, or strike a key and play classic instruments like a plucked string, bell or marimba.
Try the Synth →🗣️ Vowel Synthesizer
Shape vowels on an interactive IPA chart, with male and female voices, by tuning the formant frequencies.
Try the Vowel Synthesizer →What is additive synthesis?
Additive synthesis builds a complex sound by adding together simple sine waves at different frequencies, amplitudes and phases. Any repeating waveform can be expressed this way, which is why a handful of carefully chosen partials can approximate the character of a real instrument.
Our tools run entirely in your browser using the Web Audio API, so nothing is uploaded or recorded.
Frequently asked questions
Are these sound tools free?
Yes. They are completely free, with no signup and no limit.
Do I need to install anything?
No. The tools run in a modern browser with JavaScript and the Web Audio API.