Guides
The circle of fifths explained
Twelve keys in a ring, each a fifth away from its neighbours. It looks like a theory chart, but it answers very practical questions: which chords go together, how many sharps a key has, and where a piece can move next.
In short
- Going clockwise each key is a fifth higher and has one more sharp; counter-clockwise, one more flat.
- The inner ring holds the relative minor of each key, which shares its key signature.
- A key’s main chords sit together on the circle: the key itself, its two neighbours, and their three relative minors.
On this page
What the circle of fifths is
Start at C and go up a perfect fifth (seven semitones): you reach G. Up another fifth: D, then A, E, B, F♯… After twelve steps you are back at C, having passed every one of the twelve notes exactly once. Arrange those steps round a clock face and you have the circle of fifths.
The outer ring shows the major keys, the inner ring their relative minors. Read counter-clockwise, each step is a fourth up (or a fifth down), which is why some books call it the circle of fourths. It is the same circle.
Key signatures at a glance
C major has no sharps or flats. Each step clockwise adds one sharp; each step counter-clockwise adds one flat. At the bottom of the circle the two sides meet: F♯ major (six sharps) and G♭ major (six flats) sound identical and are written differently. Such pairs are called enharmonic keys.
| Major key | Signature | Relative minor |
|---|---|---|
| C | 0 | Am |
| G | 1♯ | Em |
| D | 2♯ | Bm |
| A | 3♯ | F♯m |
| E | 4♯ | C♯m |
| B | 5♯ | G♯m |
| F♯ | 6♯ / 6♭ | D♯m |
| D♭ | 5♭ | B♭m |
| A♭ | 4♭ | Fm |
| E♭ | 3♭ | Cm |
| B♭ | 2♭ | Gm |
| F | 1♭ | Dm |
The order of sharps and flats
Sharps are always added in the same order, itself a chain of fifths: F♯ C♯ G♯ D♯ A♯ E♯ B♯. A key with three sharps has the first three: F♯, C♯ and G♯ (A major). Flats come in the reverse order: B♭ E♭ A♭ D♭ G♭ C♭ F♭. A key with two flats has B♭ and E♭ (B♭ major).
Finding the chords of a key
This is where the circle earns its place on a guitarist’s or pianist’s wall. The six most used chords of any major key are neighbours on the circle:
- Find the key on the outer ring, say G. That is chord I.
- Its neighbours are IV (counter-clockwise, C) and V (clockwise, D).
- The three minors directly inside those are vi (Em), ii (Am) and iii (Bm).
So the key of G gives G, C, D, Em, Am and Bm, the chords behind a huge amount of popular music. (The seventh chord of the key, F♯ diminished, sits just outside this group and is used less.) Every key has its own page in our keys section with these chords spelled out, and you can hear them on the piano chord pages.
Progressions move around the circle
Chords a fifth apart sound strongly connected; the move from V to I (D to G in G major) is the strongest ending in Western harmony. Many progressions simply walk counter-clockwise round the circle towards the home key: in C major, the ii–V–I of jazz is Dm → G → C, three neighbouring steps.
Longer chains do the same: A–D–G–C is three counter-clockwise steps in a row, and E–A–D–G–C adds a fourth. When you hear a sequence of chords that keeps “falling” towards home, you are hearing the circle. Our chord progressions section shows the common ones in every key.
Everyday uses
- Reading music: count the sharps or flats, find that position on the circle, and you have the key (or its relative minor).
- Transposing: moving a piece to another key keeps its shape on the circle. Rotate it: from G (I), C (IV) and D (V) to A, D and E. A capo does the same on guitar.
- Changing key: neighbouring keys share six of their seven notes, so modulating one step round the circle sounds smooth; jumping across the circle sounds dramatic.
- Practising scales: go round the circle and add one sharp or flat at a time. Each new scale changes just one note from the last.
Why it works
A perfect fifth is the simplest interval after the octave: the frequencies are close to a 3:2 ratio, so the two notes blend strongly. Building scales from stacked fifths gives the major scale; the seven notes of C major are seven neighbouring steps of the circle, F C G D A E B. Move the window one step clockwise and you get G major, with F♯ replacing F. That single change per step is the whole logic of key signatures. Training your ear to hear fifths and fourths makes the circle audible as well as visible; see ear training basics.
Frequently asked questions
What is the circle of fifths used for?
To see key signatures, relative minors and the main chords of every key at a glance, and to transpose music or plan key changes.
How do you read the circle of fifths?
Clockwise each key goes up a fifth and gains a sharp; counter-clockwise each key goes up a fourth and gains a flat. The inner ring shows each key’s relative minor.
What are the chords in the key of C?
The main six are C, F and G (major) and Am, Dm and Em (minor). The seventh chord of the key is B diminished.
What is a relative minor?
The minor key that shares a major key’s signature. Its root is three semitones below the major root: A minor for C major, E minor for G major.
Why are there 12 keys on the circle when some keys have two names?
There are only twelve different notes. At the bottom of the circle, keys like F♯ and G♭ major are the same sound with different spellings, so they share one position.