@kentcdodds/pocket-piano

A pocket piano for choir practice: your singing part's range on your phone, installable and offline.

src/notes.ts

9 lines · 299 B · TypeScript

export const NOTE_NAMES = ['C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#', 'A', 'A#', 'B']

export function midiToName(midi: number) {
	return NOTE_NAMES[midi % 12] + String(Math.floor(midi / 12) - 1)
}

export function midiToFrequency(midi: number) {
	return 440 * Math.pow(2, (midi - 69) / 12)
}