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Chord & Fret

Bb13 — dominant thirteenth

Also written A#13 — the same chord, spelled the other way.

Notes in Bb13: Bb – D – F – Ab – C – GFormula: 1 – 3 – 5 – b7 – 9 – 13

In the formula, the numbers count steps of the major scale starting from the note that names the chord; "b" lowers a half step, "#" raises one — and a slash names the bass note.

The 13 is the full extended dominant. In practice, the third and seventh define the function while the thirteenth gives the color — the root and fifth can be omitted.

The same chord on all four instruments

Bb13, x 1 0 0 1 4Bb13123×BbDGCAb
Guitar
Bb13, x 1 0 0 1 4Bb13123×BbDGCAb
Electric guitar
Bb13, 5 3 3 6Bb1332113GBbDAb
Cavaquinho
Bb13, 0 2 4 1Bb13231GDAbBb
Ukulele

Where to use it: An elegant dominant in jazz, MPB and gospel.

Every region of the neck hides more shapes of Bb13. In Chord & Fret, you check it note by note, playing any shape as an arpeggio; open every variation on the neck, grouped by bass note; and set a capo — the diagrams redraw above it. Start free. Unlock everything with Pro. Plays offline.

See the whole neck in Chord & Fret →

Part of the Extended family.

Other chords in this family

Bbmaj9Bb9A#m9A#m11Bbmaj9(#11)Bb11Bbmaj11Bbmaj13Bbm13Bbm(maj9)

See all chord types and qualities →