Bbmaj13b13 Major 7th
The Bbmaj13b13 chord is built from the notes Bb – D – F – A – C – Gb.
Piano sound loads on first tap.
Also known as
Bbmaj9(b15)
Chord tones, one by one
BbRoot
Root
The fundamental note the chord is built on — Bb.
DThird
Major third
Four semitones — makes the chord major (brighter, happier).
FFifth
Perfect fifth
Seven semitones — the most stable interval, reinforces the root.
ASeventh
Major seventh
Eleven semitones — a lush, jazzy seventh just below the octave (maj7).
CExtension
Ninth (9)
A 9th — colorful extension a whole step above the octave.
GbExtension
Flat thirteenth (♭13)
A ♭13 — dark altered tension over a dominant chord.
🎼 Related scales
🎹 Modal analysis
This chord implies the Harmonic major scale; its characteristic note is the dark ♭6.
🎸 Genres
Jazz · Gospel · Classical