Chords and scales explorer

The scale’s notes and degrees, its key signature (modes show the major key they share notes with), the scale on a three-octave piano, and on the fretboard. There are major and the minors (natural, harmonic, melodic), the seven modes, major and minor pentatonic, minor and major blues, jazz scales (Lydian dominant, altered, Locrian ♮2, bebop dominant), whole tone, both diminished scales, chromatic, and a set of others: harmonic major, Phrygian dominant, double harmonic, Hungarian minor, Neapolitan minor and major, Persian, enigmatic, Hirajōshi, In-sen and the Egyptian pentatonic.

The fretboard follows the tuning menu — any guitar tuning, bass, ukulele, mandolin, banjo, or your own strings — with up to 24 frets and a left-handed view. Labels can be note names, scale degrees, or intervals from the tonic. Pattern narrows it to one shape:

For seven-note scales the table lists the chords built in thirds on each degree, as triads or sevenths, with Roman numerals, notes and function (tonic, predominant, dominant). Click a chord to hear it and to see its notes stand out on the piano and fretboard. Numerals count from the major scale, so natural minor reads i ii° ♭III iv v ♭VI ♭VII.

Click piano keys, or one fret per string on the fretboard, and the chord is named — with the inversion, slash chords (C/D), left-out fifths, and the other names the same notes could have (C6 or Am7/C). Spell a chord goes the other way: choose a root, one of 36 chord types and an inversion, and see and hear it.

Type any chord symbol (F#m7, Bbmaj7, Cadd9, D/F#) and every way to play it on the current tuning is found by search: every combination of open, muted and fretted strings within a four-fret stretch is tried, the ones with every needed note, the right bass and at most four fingers (a barre counts as one) are kept, and each is scored for how easy it is — stretch, fingers, barres, muted strings in the middle, open strings, and how far up the neck. Finger numbers are shown in the dots. The well-known shapes come out on top (x32010 for C, 022100 for E, 133211 for F with a barre), and the same search works for ukulele, mandolin or open tunings. Allow inversions lets a chord tone other than the root be in the bass.

The circle of fifths with relative minors and key signatures; click a key to move everything to it. The progressions — I–V–vi–IV, I–vi–IV–V, ii–V–I, 12-bar blues (and the quick-change and minor versions), the Andalusian cadence, Pachelbel, and more — are shown in the key and play on a plucked or piano sound at any tempo, looping, with the current chord lit.

Paste chords or a whole chord sheet: lines that are mostly chords are moved to the new key, lyric lines are left alone, and the spelling follows the new key (E to F turns F♯m7/C♯ into Gm7/D, not into F♯ spellings). The key is guessed from the chords, or set it yourself. The capo helper lists capo positions and the shapes you would play, best first by how many are easy open chords: B♭ E♭ F Gm becomes G C D Em with a capo on 3.