semicord

D7 D dominant seventh chord

Notes
D F# A C
Formula
1 3 5 b7
Semitones
0 4 7 10 above the root
Other symbols
Ddom7

D to F# is a major third (4 semitones), F# to A is a minor third (3 semitones), A to C is a minor third (3 semitones). A dominant seventh is a major triad plus a minor seventh (C, 10 semitones above D). It is the V chord that leads back home, and the basic chord of the blues.

D7 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C#4Eb4F#4Ab4Bb4C#5Eb5F#5Ab5Bb5C4DF#ACC5

Root position from D4: D4, F#4, A4, C5. Middle C is C4.

D7 on the guitar

Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has D as its lowest note.

××DAACCF#F#
Open position
x x 0 2 1 2 (low E to high e)
Sounds D3 A3 C4 F#4
5fr×DDAACCF#F#AA
A-shape barre, root on the A string at fret 5
x 5 7 5 7 5 (low E to high e)
Sounds D3 A3 C4 F#4 A4
10frDDAACCF#F#AADD
E-shape barre, root on the E string at fret 10
10 12 10 11 10 10 (low E to high e)
Sounds D3 A3 C4 F#4 A4 D5

The barre shapes are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play dominant seventh chords on other roots.

Inversions of D7

An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.

PositionNotes, bass firstNamedListen
Root positionD F# A CD7
1st inversionF# A C DD7/F#
2nd inversionA C D F#D7/A
3rd inversionC D F# AD7/C

Where D7 fits

D7 is V7 in G major, V7 in G minor. Its F# and C are a tritone apart (6 semitones). In G major the F# usually rises a half step to G and the C falls a half step, which is why D7 pulls so strongly towards G.