Chord & FretD7 · Ukulele
A doorbell ringing with nobody answering. A phone buzzing face-down on the table. Some things only exist to be resolved — D7 is their musical version. Give the audio below a listen and feel the unfinished business.
Listen first
What you just heard
Why does it sound unfinished? Inside D7, two notes are at odds: F# and C. Play the arpeggio again, no rush and catch the second and the last note — the distance between them is the tritone, the tensest interval tonal music knows. D and A keep the house standing while those two argue inside it. And an argument, you know, demands a resolution.
Now it's your hands' turn
On the ukulele, the high reentrant G makes every shape light — and with four strings, every note is exposed. So grab the first position below; it's also the easiest one to play. Now the experiment that explains this chord better than any explanation: play D7, let it ring a moment, then play G. Felt the door close? Do it again. That relief is the reason this chord exists.
1 more shape of this chord on the neck
Part of 218,399 voicings and inversions in Chord & Fret Pro — see and play every one.
Precision Tuner — Before you play these shapes, get in tune — chromatic tuner and reference tones · see it in Chord & Fret
The other positions earn their keep in blues and jazz, where this chord is practically the official language; learn them one at a time.
Left-handed? Mirror's right here
What is D7?
D7: D Major with Seventh. The notes are D, F#, A, C (fixed-do: Re, Fa#, La, Do) — the degrees 1–3–5–b7.
Where this chord lives
Its job is fixed: D7 is a dominant, and dominants live as VII7 in E minor, V7 in G major. Translation: wherever it shows up, the music is about to move. A chart full of 7th chords is a song that won't sit still.
Transpose & Capo — Need it in another key? Move the whole chart and find the easiest capo · open in Chord & Fret
Identify Chord — Found a shape on your own fretboard? The app names it back · use it in Chord & Fret
Where it tends to go
Treating D7 as the home chord (I) of its key, it tends to go toward the pre-dominant (Em / G) or the dominant (A / C#°) — and the dominant pulls back home. Typically, not a rule.
Every shape of D7 lives in Chord & Fret Pro — 4 instruments, 16 tunings, 41 chord types and 57 scales, in every key. Start free. Unlock everything with Pro. Plays offline. Made by musicians, no ads.
When you want to go further
For soloing, D Mixolydian (D E F# G A B C · 1 2 3 4 5 6 b7: the major scale with a lowered seventh — the blues accent); D Lydian dominant (D E F# G# A B C · 1 2 3 #4 5 6 b7: a mixolydian with a raised fourth: the dominant in formalwear) cover the whole chord. And look at the first swap on the list below: that's the famous tritone substitution, the twin dominant living three whole steps from here, the one arrangers reach for when they want to arrive at the same place by a prettier road.
D Mixolydian
4 more scale positions on the neck
That's 35,178 mapped scale shapes in Chord & Fret Pro, ready to play.
The same D Mixolydian in its main shapes along the neck — pick whichever position sits under your hand. The rings mark the guide notes (the 3rd and 7th) that carry this chord's color.
Scale — The whole scale on the neck — in boxes or three notes per string, with an exercise and a tempo ramp · open in Chord & Fret
Improvising in context
To improvise over D7 as home, the D Mixolydian scale fits entirely — it contains every note of the chord. And when the dominant (A) pulls back, the leading tone C# is the note that wants to resolve home.
Swaps that work:
- Ab7Ab7Ab7Ab7 — Tritone substitution (shared 3rd–7th tritone)
- Am7Am7Am7Am7 — Forms a II–V: precede with this ii
- Ebdim7 — Passing diminished (ascending)
Reharmonize — Want richer substitutions? Reharmonize the progression in a tap · try it in Chord & Fret
The question this page asked has a one-click answer: G. Don't end the day without playing both in a row.