B7

B Dominant 7th — the engine of harmonic motion — the tritone between its third and seventh drives resolution down a fifth.

The keys
C4C5C6
B – D♯ – F♯ – A
What's inside B7
NoteInterval from rootDegree
BRoot1
D♯Major 3rd3
F♯Perfect 5th5
AMinor 7thb7
Inversions
PositionKeys (low → high)
Root positionB4 – E♭5 – G♭5 – A5
1st inversionE♭5 – G♭5 – A5 – B5
2nd inversionG♭5 – A5 – B5 – E♭6
3rd inversionA5 – B5 – E♭6 – G♭6
A working voicing

Split the chord between two hands the way working players do — a solid shell low down, the colour tones up top:

HandKeys
Left (shell)B2 – A3
Right (colour)E♭5 – G♭5
Where B7 lives

Resolving down a fifth

B7 → E

The defining dominant move: the tritone inside this chord releases onto the chord a fifth below.

In a ii–V–I

G♭m7 → B7 → Emaj7

This chord as the V — the engine of the most-used cadence in music.

Put B7 under your fingers

Hear every voicing, see the keys light up, and drill it in the interactive Chord & Voicing Lab.

Open the Chord & Voicing Lab →
Dominant 7th in every key
C7 C♯7 D7 E♭7 E7 F7 F♯7 G7 A♭7 A7 B♭7