Chord & FretB7 · Ukulele
Breathe in right now. Hold it. ...Feel your body asking for the second half? B7 is a song breathing like that — first half only. Hit play below.
Listen first
What you just heard
Why does it sound unfinished? Inside B7, two notes are arguing: D# and A. Now listen to the arpeggio, one note at a time and catch the second and the last note — the distance between them is the tritone, the tensest interval tonal music knows. B and F# 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; the position marked with ⭐ is the easiest to play. Now the experiment that explains this chord better than any explanation: play B7, hold it for one breath, then play E. Felt the door close? Do it again. That relief is the reason this chord exists.
1 more shape of this chord on the neck
That's 218,399 voicings and inversions in Chord & Fret Pro, ready to play.
Precision Tuner — Before you play these shapes, get in tune — chromatic tuner and reference tones · open 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.
Every shape of B7 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. Free to start, no card needed.
Left-handed? Mirror's right here
What is B7?
B7: B Major with Seventh. The notes are B, D#, F#, A (fixed-do: Si, Re#, Fa#, La) — the degrees 1–3–5–b7.
Where this chord lives
Its job is fixed: B7 is a dominant, and dominants live as VII7 in C# minor, V7 in E major. Plainly: where it enters, the song is about to leave the room. 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 · see it in Chord & Fret
Identify Chord — Found a shape on your own fretboard? The app names it back · try it in Chord & Fret
Where it tends to go
Treating B7 as the home chord (I) of its key, it tends to go toward the pre-dominant (C#m / E) or the dominant (F# / A#°) — and the dominant pulls back home. It's a tendency, not a law.
When you want to go further
For soloing, B Mixolydian (B C# D# E F# G# A · 1 2 3 4 5 6 b7: the major scale with a lowered seventh — the blues accent); B Lydian dominant (B C# D# E# F# G# A · 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.
B Mixolydian
4 more scale positions on the neck
That's 35,178 mapped scale shapes in Chord & Fret Pro, ready to play.
The same B 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 · see it in Chord & Fret
Improvising in context
To improvise over B7 as home, the B Mixolydian scale covers it whole — it contains every note of the chord. And when the dominant (F#) pulls back, the leading tone Bb is the note that wants to resolve home.
Swaps that work:
- F7F7F7F7 — Tritone substitution (shared 3rd–7th tritone)
- Gbm7Gbm7Gbm7Gbm7 — Forms a II–V: precede with this ii
- Cdim7 — Passing diminished (ascending)
Reharmonize — Want richer substitutions? Reharmonize the progression in a tap · use it in Chord & Fret
You already know how this sentence ends. The period after B7 is called E — go there and close it with your own fingers.