The Complete Dominant 7th · Intermediate Theory & Ear Training
One restless chord, a whole family of colours. We start from the very beginning — how you build it — then tour every kind, voice each the way a pianist actually plays it, and follow it all the way home: resolution.
Before we colour it, alter it or resolve it, we have to build it. A dominant 7th is four notes stacked in thirds — and there are three ways to see it. Two of them we'll learn right now; the third (a tritone pair) has a chapter of its own later. The more ways you can hold a chord in your mind, the faster you'll find it under your hands.
Take a plain major triad (1 · 3 · 5) and drop one more third on top — a minor 7th above the root, the ♭7. That's it. On A: the A-major triad A · C♯ · E, plus G — A7.
Quick way to find that ♭7: it's “octave minus 2” — two semitones below the root's octave. From A up to the next A, come down two — that's G.
The major 3rd makes it bright; the ♭7 makes it lean. Together they are the tension the whole lesson is built on.
Skip the root and look up a major 3rd: the notes 3 · 5 · ♭7 form a diminished triad. So A7 is a C♯ diminished triad (C♯ · E · G) sitting over an A in the bass.
This is how pianists actually grab it — root down low, the tritone-rich triad up top. It's the seed of every voicing in Part Three.
Raise that ♭7 by a half-step and you get a major 7th (A · C♯ · E · G♯ = Amaj7). Those two chords look almost identical but behave like opposites: the maj7 is at home and relaxed — it belongs to the key. The dominant 7 is a restless outsider that leans somewhere else. Find the difference by ear and you can hear a dominant anywhere. One semitone, two completely different jobs.
Pick any root and watch the chord assemble: the major triad first, then the ♭7 that turns it dominant. The keyboard shows where your hands go; press play to hear each step.
The 3rd and the ♭7 you just stacked sit a tritone apart. Those two notes are the chord's identity — its guide tones — and everything from here bends, stacks or drops notes around them without ever losing that pair.
Try this exercise away from the keys: sing the major triad (1 – 3 – 5), then reach up and add the ♭7 on top. “B major… plus A.” Then move the added note into different octaves and inversions — you'll hear the same dominant colour in four shapes. Training your ear to hear “triad + ♭7” is how you'll recognise a dominant 7th anywhere.
Got a MIDI keyboard plugged in? Connect it and the site will name whatever you play in real time — every dominant, alteration, triad and 7th chord — and light up the notes. The best way to learn these shapes is under your own fingers. (Works in Chrome/Edge; no keyboard needed to read the rest of the lesson.)
Play A · C♯ · E — it says “A”. Add G on top — now it says “A7”. Slide that G up to G♯ — “Amaj7”. Flatten the 9 (add B♭) — “A7♭9”. Watch the name change as you build every chord from the lesson by hand.
A dominant 7th is 1 · 3 · 5 · ♭7 — on A, that’s A C♯ E G. Inside it, the 3rd (C♯) and the ♭7 (G) sit a tritone apart. That single restless interval is the whole reason this chord exists: it leans, and it wants to fall home.
Those two notes — the 3rd and the ♭7 — are the guide tones. They are the chord’s identity. Keep them, and you can bend, stretch, drop or pile on almost anything else; it’s still a dominant. Lose them, and it isn’t.
Everything in this lesson is one chord wearing different clothes over the same skeleton.
Throughout, the chords are written on a grand staff: the left hand holds the foundation (root + ♭7) on the bass clef, the right hand plays the colour up top. That split is not decoration — it’s how these chords are actually played. More on the method in the voicing chapter.
Before we alter anything, we can simply make the chord taller by stacking more thirds: add the 9th, then the 13th. These are consonant, singing colours — the everyday sound of funk, soul and gospel.
Push the 3rd up one step to the 4th and the chord goes weightless — the leading tone is suspended, waiting. The 9sus4 (the “gospel sus”) adds a 9th for that creamy, quartal neo-soul sound.
A 7sus4 usually falls to a plain 7 (the 4th drops to the 3rd) before resolving — a suspension inside the dominant. We’ll hear it land in the resolution chapter.
The 5th is the most expendable note in the chord, so it’s the first we bend. Lower it (7♭5, whole-tone and weightless) or raise it (7♯5, augmented and lifting).
Now knock the 9th out of tune. The ♭9 is dark and dramatic — a diminished chord lives inside it. The ♯9 rubs the major 3rd against a sharp 9th (≈♭3): the gritty “Hendrix” colour.
A7♯9’s top note is written B♯ (a raised ninth), not C — same key, correct name. And hidden in A7♭9 is a C♯ diminished 7th: the 3-5-♭7-♭9 stack is a diminished chord. That’s its secret.
Two more colours, often misunderstood. The 7♯11 (the Lydian dominant) keeps its natural 5th and floats a ♯11 above — bright, filmic, non-resolving. The 7♭13 lowers the 13th for a smoky weight.
7♭5 vs 7♯11: a ♭5 replaces the 5th; a ♯11 adds to it (both 5 and ♯11 present). 7♯5 vs 7♭13: the same black key (E♯ = F), but ♯5 replaces the 5th while ♭13 implies the 5th is still around. Spelling tells you the function.
Combine an altered 5th with an altered 9th and you get the four classic altered dominants. Take all the alterations together and you get 7alt — the altered scale’s chord, and the default jazz V before a minor chord.
That’s the whole family. Below, you can summon and hear every one of the sixteen — and the next section explains exactly how each voicing was built.
Pick a root and any of the sixteen chords. The grand staff shows the professional two-hand voicing, the keyboard splits it into hands, and where a shortcut exists, the upper-structure triad appears.
These aren’t notes stacked in root position — that would be unplayable and muddy. Each voicing follows the same handful of rules real pianists use. Learn the rules and you can voice any dominant on sight.
Once the left hand holds root + ♭7, the right hand often spells a plain triad you already know. Grab the triad, get the whole altered chord:
Two upper structures worth memorising, both built a whole tone below the root:
Same hand shape, dropped a whole step — instant extension.
Everything so far keeps the root in your left hand. But play with a bassist — or walk your own bass — and the root is already covered. Jazz pianists drop it and keep only what matters: the guide tones plus the colour. Four notes, one hand.
There are two classic shapes, named for which guide tone sits at the bottom:
These sit in one hand around middle C — which frees the right hand to play the melody or solo. They are the everyday voicings of every jazz pianist’s ii–V.
With no root, the chord’s identity rides entirely on the guide tones — the same tritone we stacked when we first built the chord. That’s the proof of the whole lesson: keep the 3rd and ♭7 and the dominant survives anything, even losing its own root.
Remember the tritone — the 3rd and ♭7 leaning on each other? Resolution is simply letting that tension collapse. The dominant falls a fifth (counter-clockwise on the circle) and its guide tones step into the new chord.
The motion is beautifully economical. From A7 to D:
Two voices barely move, and the whole world changes. That is voice leading.
A dominant can land on a major or a minor chord. In gospel especially, altered dominants love to resolve to a minor — A7alt → D minor. Hear both in the Lab below.
Don't just play it — sing it. Put the ♭7 on top and sing it falling a half-step to the 3rd of the home chord (the 4→3 pull). Then sing the 3rd rising a half-step to the tonic (the leading-tone 7→1 pull). Those two tiny moves are the magnetism. Train your ear to hear the cadence, not the lone chord — it's far easier to recognise “this wants to go home” than to name a chord in isolation.
Choose a dominant, choose its home, and watch the guide tones move. Then press play and feel the lean-and-land.
The home cadence. A7 → D (or Dm). The strongest resolution there is.
E♭7 → D. E♭7 shares A7’s exact tritone (G + C♯), so it pulls to the same home — now with a smooth ♭2→1 bass. The secret behind countless jazz turnarounds.
A7 → B♭ (or Bm). The ear expects D; you give it a neighbour instead. Surprise and delay.
C7 → D. A dominant a whole step below the target (♭VII7) sneaks in through the back door — a gospel and Steely-Dan favourite.
A7sus4 → A7 → D. Delay the 3rd with a 4th, let it fall, then resolve. Tension stacked on tension.
B♭7 → A7 (or up: A♭7 → A7). Approach a dominant from the dominant a semitone above or below and just slide — the whole chord shifts in parallel. It's the engine of Jailhouse Rock, and a spicy way to arrive.
Strings of dominants round the circle — E7→A7→D7→G — are how whole tunes travel. Each is a V pulling to the next.
Dominants don't only announce themselves at cadences. Very often one appears for a single beat — created by a voice quietly moving by half-steps while the chord underneath barely changes. You've heard these a thousand times without naming them.
Hold a C chord and walk the top voice down chromatically:
C → Cmaj7 → C7 → F
The top note falls C → B → B♭, and on that B♭ the chord momentarily becomes a C7 — a secret dominant that then pulls to F. That's the guitar figure in the Beatles' “Something.”
Walk a bass line up and each passing chord becomes a dominant of the next:
C → A7/C♯ → Dm → …
That A7 in the middle is a secondary dominant (V7/ii) — a slash chord hiding a dominant, nudging the ear toward D minor. Heard all over “(Can't Help) Falling in Love.”
In Dorian (a minor scale with a natural 6th), the IV chord turns into a dominant 7th. Vamp i m7 → IV7 (say E♭m7 → A♭7) and you get that endless funk groove — a dominant used purely for colour, never resolving. Same chord, a completely different job.
All that motion has a map. On the circle of fifths, a dominant’s pull home is simply one step counter-clockwise — and every alternative route (tritone sub, backdoor, deceptive, whole chains) is a shape you can see. Pick a home key and a method; watch the road light up on the wheel, then hear it resolve.
Every step counter-clockwise is a perfect-fifth fall. That’s why V→I, chains of secondary dominants, and even the ♭II tritone sub (sitting directly across the wheel, sharing the same tritone) all feel like coming home — they are all just travelling the same circle by different roads.
Here is the third way to think about a dominant 7th — and a composer's favourite trick. A dominant's whole identity is its tritone (the 3rd + ♭7). Two different dominants, a tritone apart, share the exact same tritone — so either one can do the job. Play the guide tones in your right hand, and you can swap the bass to get two dominants for the price of one.
Put the two guide tones (3 and ♭7) in your right hand and leave them there. In the left hand, alternate the root + 5th of each partner — B & F♯, then F & C. Same right hand, two basses, two dominants. That muscle memory is the whole trick.
Here is the whole point of the family. Alterations aren’t decoration — they are degrees of tension, and tension is a dial, not a switch. The plain 7 leans politely; the 7alt grabs the music by the collar. Same V, same home — you choose how hard it pulls.
Three rules govern how professionals spend tension:
7 — plain lean → 9 — warm lean → 13 — lush lean → 7♭9 — dark pull → 7alt — maximum grip. Every step keeps the same tritone engine; each adds more rub, so the collapse into home feels bigger. Turn the dial below and hear the same phrase transform.
Not “can you play a 7♭9” — but choosing the right lean for the moment: gospel reaching for a minor vi wants the dark ♭9; a pop chorus heading to a bright I wants a clean 9; a ballad’s last cadence earns the full alt. Turn the dial with intention, and resolution stops being theory and becomes phrasing.
Every dominant chord carries a scale inside it — the pool of notes that melodies, fills and solos draw from over that chord. Notice the order we did this in: chord first, scale second. Scales are children of chords — the scale simply spells out the notes the chord already implies. Match the scale to the alteration and everything you play agrees with the harmony. These seven cover the entire family.
A scale “works” over a dominant only if it contains the root, the major 3rd and the ♭7 — that tritone is the chord's identity. The perfect 5th is optional. That single rule instantly rules out the plain major scale (it has a natural 7) and lets in everything below.
And here's the tidy secret: every seven-note dominant scale is just a mode of melodic or harmonic minor — Lydian dominant is the 4th mode of melodic minor, the altered scale its 7th, Mixolydian ♭13 its 5th, and Phrygian dominant the 5th of harmonic minor. Learn two parent scales, own them all.
The scale simply contains the chord. Plain dominant → plain Mixolydian. Sharpen the 11? Lydian dominant. Flatten the 9? The diminished scale (or Phrygian dominant, heading to minor). Alter everything → the altered scale. In the Explorer above, every chord now names its scale — select any chord and play its scale to hear chord and colour agree.
So far our dominant was the V of the key. But any chord can be handed its own leading-tone pull — and there are two ways to do it. The secondary dominant (V7/x) borrows that chord’s V7; the secondary diminished (vii°7/x) borrows its leading-tone diminished 7th. And here is the secret that ties the whole lesson together: they are the same chord — a diminished 7th is a 7♭9 with its root removed.
Earlier we found a C♯°7 hiding inside A7♭9 (A · C♯ · E · G · B♭ — just drop the A). So C♯°7 → Dm and A7♭9 → Dm are the same pull with the same tritone. Every secondary diminished is a secondary dominant wearing a disguise — which is exactly why it lives here in the dominant family.
| Target chord | Secondary dominant | Secondary diminished | Hear both |
|---|
One borrowed leading tone is a raised eyebrow; a chain of them (E7→A7→D7→G7→C) is a journey home around the circle — the engine of ragtime, gospel turnarounds and jazz standards. Dominants or diminisheds, altered or sus’d or tritone-subbed — all the same wheel, all the same pull.
Here is the most useful trick a diminished 7th hides. Because it is built of equal minor thirds, it is perfectly symmetrical — it looks the same from all four notes. So a single diminished 7th is the top of four different dominant 7♭9 chords, each a minor 3rd apart, and each pulls home to a different minor key. Slide a bass underneath and choose your destination.
| Bass added | Becomes | Resolves to | Hear |
|---|
Every dominant 7♭9 is a major triad + ♭7 + ♭9 (from the very first chapter) — and its top four notes spell a diminished 7th. Flip which note you call the root and the same diminished shape becomes four different 7♭9 chords, each a minor 3rd apart. And here's the kicker: there are only three unique diminished 7th chords in all of music — learn those three and you own every 7♭9 in every key. The pianist's ultimate shortcut.
Notice these all resolve down a semitone into a minor chord, and it sounds beautiful. Push the same notes up instead and it sounds wrong. That's designed not by Mozart or Bach — by Mother Nature. The ♭9 leans down onto the 5th of the new chord; the tritone collapses inward. Gravity, in sound.
Everything in the resolution chapter said a dominant must fall home. The blues says: no. In a blues, the I chord, the IV chord and the V chord are all dominant 7ths — the tension never resolves, and that permanent lean is the sound of the blues.
The 12-bar form in the chosen key — every chord a dominant 7th, none of them going anywhere:
Here the I7 isn’t tense — it is the tonic. Funk vamps (one dominant 9th or 13th, forever), soul grooves and modal jazz all live on this idea: the dominant as a stable colour, not a question needing an answer.
Remember the Hendrix chord? Over a blues tonic, the ♯9 is simply the blue note — the minor 3rd sung on top of a major-3rd chord. The 7♯9 is the blues, captured in a single voicing.
Soak your ear in dominant 7ths: B.B. King, Ray Charles, John Mayer and “Stormy Monday” for the blues; Queen, Elton John and Billy Joel for dominants driving pop and rock. The fastest way to own this chord is to keep hearing where it lives.
Reading about a dominant is one thing; hearing it is the goal. Pick a challenge, press play, and name the sound. Your streak is at the top — the notes are chosen at random in a fresh key each time, so you can't memorise the answer, only learn the sound.
| Chord | Formula | Notes | Two-hand voicing | Scale colour | Character |
|---|
Transpose any of these in the Explorer above. Left hand | right hand shown for the playing voicing.
You now have the whole dominant 7th family — every chord type, every voicing (rooted and rootless), every scale colour, and every way it moves: resolving home, borrowing keys as a secondary dominant, or refusing to resolve at all in the blues. From here, the natural next step is putting them to work inside real ii–V–I progressions and tunes — the dominant is the engine; now you can drive.