🎛️ Audio Visualizer Web Audio API — zero libraries

The browser has a full audio-processing graph built in: oscillators, filters, spatializers, and an FFT analyser. Point the analyser at your microphone and paint the spectrum every frame. Hum. Whistle. Play music at your laptop.

The audio never leaves your machine — the analyser is local math.

The pipeline:

getUserMedia({audio}) → MediaStreamSource → AnalyserNode →
        getByteFrequencyData()

into a canvas loop. This is the same idea as the audio-visualizer web component — the component just wraps these ~50 lines in a tag.
← Plain JS