Key Detection

Infer the tonic key from a chord sequence.

Functions

detectKey

detectKey(chords: Chord[], declaredKey?: string | null, config?: DetectKeyConfig): string | null

Infer the tonic key from a chord sequence. Returns a key string (e.g. `'Am'`, `'G mixolydian'`) or `null` if no key scores above the minimum confidence threshold. If `declaredKey` is provided and scores above zero, it is returned unchanged unless it has zero diatonic overlap with the chords.

Types

DetectKeyConfig interface

Options for `detectKey`.

forceKey?: string

Skip scoring entirely and return this key string.

fSharpOrGFlat?: "f-sharp" | "g-flat"

Resolve the ambiguous F♯/G♭ enharmonic key to one spelling. Defaults to `'f-sharp'`.