Circle of Fifths Explained: Chart and How to Use It

The circle of fifths arranges the 12 major keys so each neighbour is a perfect fifth (7 semitones) apart. Clockwise from C, each key adds one sharp; counter-clockwise, one flat. Each relative minor sits inside its major. Use it to read key signatures, find related chords and plan key changes; the music key chart lists every key’s notes.

The circle of fifths chart

C major sits at 12 o’clock with no sharps or flats. Each step clockwise goes up a fifth (C → G → D) and adds a sharp; each step counter-clockwise goes down a fifth, the same as up a fourth (C → F → B♭), and adds a flat. At 6 o’clock, F♯ major (6 sharps) and G♭ major (6 flats) sound the same, so the circle closes. Two more pairs overlap: B = C♭ major (7 flats) and D♭ = C♯ major (7 sharps); the spelling with fewer accidentals is the usual one.

Why fifths? The 3:2 interval behind the circle

A perfect fifth is the interval from C up to G: 7 semitones. In pure tuning its two notes vibrate in a 3:2 ratio, the simplest ratio after the octave (2:1), which is why fifths sound so stable. A above middle C is 440 Hz; the fifth above it, E, is 660 Hz in pure tuning and 659.26 Hz on a modern piano.

Stack 12 fifths and you land back on the starting note, 7 octaves higher, because 12 × 7 semitones = 84 = 7 × 12. On a piano this closes exactly because each equal-tempered fifth is 700 cents, 1.96 cents narrower than a pure fifth (701.96 cents). Twelve pure fifths overshoot by 23.46 cents, the Pythagorean comma; equal temperament spreads that gap so every key is usable. Check any interval with the semitone calculator.

The circle appears in treatises from the 17th century on, from Nikolai Diletsky’s Grammatika (1679) to Johann David Heinichen’s books of 1711 and 1728 (history of the circle of fifths).

Reading key signatures from the circle

The number beside each key is its key signature: the sharps or flats written at the start of each line of sheet music. They are added in a fixed order:

• Order of sharps: F♯ C♯ G♯ D♯ A♯ E♯ B♯ (memory aid: Father Charles Goes Down And Ends Battle). Each new sharp is the 7th note of the new key: G major adds F♯, D major adds C♯.
• Order of flats: B♭ E♭ A♭ D♭ G♭ C♭ F♭, the same letters backwards (Battle Ends And Down Goes Charles’ Father). Each new flat is the 4th note of the new key: F major adds B♭, B♭ major adds E♭.
• Name the key from a signature: with sharps, go up a half step from the last sharp (last sharp C♯ → D major). With flats, the second-to-last flat is the key (B♭ E♭ A♭ → E♭ major). One flat alone is F major.

What a key is, and how the tonic and scale define it, is covered in what is a song key.

Relative minor keys on the inner ring

Every major key shares its key signature with one minor key, its relative minor. It starts on the 6th note of the major scale, 3 semitones below the major tonic: C major ↔ A minor, G major ↔ E minor, E♭ major ↔ C minor. Same seven notes, different home note.

Relative is not parallel: C minor, the parallel minor of C major, keeps the tonic but has three flats. The major to minor converter can move a song to either one.

All 12 keys: signature, relative minor and neighbours

The circle of fifths as a table, clockwise from C

Major key	Key signature	Relative minor	Neighbours (IV · V)	Their relative minors (ii · iii)
C major	none	A minor	F (IV) · G (V)	Dm · Em
G major	1 sharp (F♯)	E minor	C (IV) · D (V)	Am · Bm
D major	2 sharps (F♯ C♯)	B minor	G (IV) · A (V)	Em · F♯m
A major	3 sharps (F♯ C♯ G♯)	F♯ minor	D (IV) · E (V)	Bm · C♯m
E major	4 sharps (F♯ C♯ G♯ D♯)	C♯ minor	A (IV) · B (V)	F♯m · G♯m
B major	5 sharps (F♯ C♯ G♯ D♯ A♯)	G♯ minor	E (IV) · F♯/G♭ (V)	C♯m · D♯m/E♭m
F♯ / G♭ major	6 sharps (F♯ C♯ G♯ D♯ A♯ E♯) or 6 flats as G♭	D♯ / E♭ minor	B (IV) · C♯/D♭ (V)	G♯m · A♯m/B♭m
D♭ major	5 flats (B♭ E♭ A♭ D♭ G♭)	B♭ minor	F♯/G♭ (IV) · A♭ (V)	D♯m/E♭m · Fm
A♭ major	4 flats (B♭ E♭ A♭ D♭)	F minor	D♭ (IV) · E♭ (V)	B♭m · Cm
E♭ major	3 flats (B♭ E♭ A♭)	C minor	A♭ (IV) · B♭ (V)	Fm · Gm
B♭ major	2 flats (B♭ E♭)	G minor	E♭ (IV) · F (V)	Cm · Dm
F major	1 flat (B♭)	D minor	B♭ (IV) · C (V)	Gm · Am

The five keys in a row’s last three columns are its closely related keys, one note different at most: the safest targets for a key change.

Using the circle for chord progressions

Take any major key and its two neighbours. Their three major chords are the key’s I, IV and V chords, and the three minors below them are ii, iii and vi. Only the diminished vii° chord is missing. For G major:

• Majors: C (IV) · G (I) · D (V).
• Minors: Am (ii) · Em (vi) · Bm (iii).
• Leftover: F♯dim (vii°), built on the note one half step below G.

Moving counter-clockwise, down a fifth at a time, gives the strongest resolutions. V → I (D → G) is the basic cadence; ii–V–I (Am–D–G) is a staple of jazz; and vi–ii–V–I (Em–Am–D–G) falls by a fifth three times in a row. If you know a song’s chords, the circle also narrows down its key, a method shown step by step in how to find the key of a song.

Transposing and modulating to nearby keys

A key change inside a song is called a modulation, and the distance between the two keys on the circle predicts how it will sound. Each clockwise step moves the tonic up 7 semitones (or down 5), each counter-clockwise step up 5 (or down 7). Count the steps, then read the table:

Distance on the circle vs semitones and shared notes (calculated)

Steps apart	Example from C (clockwise · counter-clockwise)	Semitones up to the new tonic	Notes shared with C	Typical effect
0	C → C	0	7 of 7	No change
1	C → G · C → F	+7 · +5	6 of 7	Smooth, often hardly noticed
2	C → D · C → B♭	+2 · +10	5 of 7	Clear but natural
3	C → A · C → E♭	+9 · +3	4 of 7	Noticeable lift or drop
4	C → E · C → A♭	+4 · +8	3 of 7	Bold
5	C → B · C → D♭	+11 · +1	2 of 7	Very bold
6	C → F♯/G♭	+6 (or −6)	2 of 7	Most distant key

This explains the pop “truck driver” key change: raising the last chorus one semitone, C → D♭, jumps five steps to a key sharing only two notes, so it sounds like a sudden lift. A move to G or F keeps six notes and slips by almost unnoticed. For audio, a key change is a pitch shift; key change vs pitch change explains the difference.

To put a song into a new key, work out the semitones with the semitones-to-change-key table. For chords and sheet music use transpose music online (how to transpose a song shows how). For a recording, the online key changer shifts the audio at the same speed (how to change the key of a song). Singers can pick a key with what key should I sing in.

How to memorise the circle of fifths

1. Learn the sharp side as a word chain: C G D A E B F♯. Each letter is a fifth above the last.
2. Learn the flat side the same way: F B♭ E♭ A♭ D♭ G♭, each a fifth below the last.
3. Steps from C = number of sharps or flats: A is 3 steps clockwise, so A major has 3 sharps. For the inner ring, go 3 semitones down: E major → C♯ minor.

Frequently asked questions

What is the circle of fifths used for?

For reading key signatures, finding a key’s relative minor, seeing which chords belong together and choosing a nearby key for a key change or transposition.

How many semitones is a fifth?

A perfect fifth is 7 semitones, for example C to G. A fourth is 5 semitones, so one step counter-clockwise (down a fifth) lands on the same note as going up a fourth.

Why is it called the circle of fifths and not fourths?

Clockwise, each key is a fifth above the last. Read counter-clockwise, the same circle is a circle of fourths; both names describe the same diagram.

How do I find the relative minor of a key?

Go to the 6th note of the major scale, or count 3 semitones down from the tonic. On the chart it is the inner-ring key directly below the major key.

Can the circle of fifths tell me what key a song is in?

It helps: a song’s chords usually fit inside one key and its two neighbours. For an audio file, the song key finder reads the key directly (how our tools work). More theory is in our pitch and key guides, every tool is on all pitch tools, and the online pitch changer is on the home page.