Build a Morse Code Practice App with the Web Audio API: Oscillator, Timing Engine, and Real-Time Feedback

Most Morse code trainers are either toy web pages with sloppy timing or native apps you have to install. There is a better option: the browser already ships everything you need for a serious practice tool. The Web Audio API gives you sample-accurate sound synthesis, and a few dozen lines of JavaScript give you a timing engine precise enough for real training. In this tutorial you will build a working Morse practice app — oscillator, timing engine, encoder, and a feedback loop that scores your keying — and learn the DSP fundamentals underneath.

Why the browser is a legitimate Morse instrument

Morse code is audio-first. Learning it from charts trains your eyes; fluency lives in your ears.…