DemoInstrument Tuner is a chromatic and instrument tuner that runs in the browser. Play a note and it shows the note name with its octave, such as A4, the exact frequency it hears, and how many cents sharp or flat you are on a needle gauge that turns green inside 5 cents. Pick guitar (standard, Drop D, DADGAD, Open G or 7-string), 4- or 5-string bass, ukulele, violin, viola, cello, double bass, mandolin or banjo and it follows whichever string you play, or tap a string to hear its pitch and lock onto it. A reference tone plays any note or any typed frequency from 20 Hz to 20 kHz, and A4 can be set anywhere from 400 to 480 Hz. Pitch detection uses the McLeod Pitch Method and reads test tones to within a cent from a bass's low E upward; audio never leaves your device. Works on phones and desktops. Built with React, TypeScript and the Web Audio API.