Procedural audio is the generation of sounds from algorithms rather than samples. In a game context, procedural audio is a form of sound synthesis where sounds are created in real-time according to a set of programmatic rules and live input. This allows the procedural sounds to have infinite variety and far less storage requirements, and to depend on the game state. The Web Audio API allows procedural sound to be generated directly in the browser, making it an excellent tool for demonstrating procedural sound development, as well as for deployment in many online games. This tutorial will take the audience through the concepts behind procedural audio, the basics of the Web Audio API (and other relevant audio development environments), and the state of the art for research in this field. It will include live, practical coding of a procedural audio system, with audio demonstrations.