Circle of Fifths — Click a Key to See Its Signature, Relative Key, and Chords
An interactive circle of fifths showing all 12 major keys. Click any key to instantly see its key signature (number of sharps/flats), relative minor, and diatonic chords.
All 12 keys: signatures and relative minors
| Key (major) | Key signature | Relative minor |
|---|---|---|
| C | No sharps or flats | Am |
| G | ♯1 | Em |
| D | ♯2 | Bm |
| A | ♯3 | F#m |
| E | ♯4 | C#m |
| B | ♯5 | G#m |
| F#/Gb | ♯6 / ♭6 | D#m/Ebm |
| Db | ♭5 | Bbm |
| Ab | ♭4 | Fm |
| Eb | ♭3 | Cm |
| Bb | ♭2 | Gm |
| F | ♭1 | Dm |
F# and Gb are enharmonic equivalents (the same pitch spelled two ways), so they are shown together as a single slot for convenience.
What the circle of fifths shows
The circle of fifths arranges the twelve major keys around a circle, exploiting the fact that **rising by a perfect fifth twelve times takes you through every key and back to where you started.** Moving clockwise from C at twelve o'clock to G, D, A and so on adds one sharp to the key signature at each step; moving anticlockwise to F, B♭, E♭ adds one flat. Rather than memorising the key signatures, you can derive them from these positions — which is the whole value of the diagram.
Click a key here and the tool shows its key signature, its relative minor and its diatonic chords. **The outer ring holds the major keys and the inner ring at the same angle holds the relative minor**, the two sharing a key signature. Because neighbouring keys on the circle share most of their notes, it also works as a map when looking for somewhere to modulate to. When composing or improvising and wondering where you can go next, the circle of fifths is the quickest tool to hand.
How to use the circle
- Click a key Select any key on the circle to bring up its details.
- Check the key signature You see how many sharps or flats apply. Clockwise adds sharps, anticlockwise adds flats.
- Look at the relative minor The inner ring shows the minor key that shares the same signature.
- Review the diatonic chords The seven chords available in that key are listed with their roman numerals.
- Try a neighbouring key When hunting for somewhere to modulate, start with the keys next door.
Tips for getting more out of it
- Starting at C at the top (12 o'clock) and moving clockwise adds one sharp per step; moving counter-clockwise adds one flat per step.
- The outer ring shows major keys, and the inner ring at the same angle shows the relative minor. Learning major/minor pairs together makes key signatures much easier to memorize.
- Neighboring keys share many common tones, so when modulating during composition or improvisation, try moving to an adjacent key first for a smoother transition.
- In the diatonic chords table, uppercase Roman numerals (I, IV, V) are major chords, lowercase (ii, iii, vi) are minor chords, and vii° is a diminished triad.
- Some keys, like F# and Gb, have two valid spellings for the same pitch (enharmonic equivalents); in practice, the spelling with fewer accidentals is usually preferred.
Where this helps
Recalling a key signature quickly
Work backwards from the number of sharps or flats at the head of a piece to identify the key.
Finding somewhere to modulate
Adjacent keys share most of their notes and move smoothly; distant keys produce a far more dramatic effect.
Building a chord progression
Having the diatonic chords laid out makes it much easier to assemble a progression that hangs together.
Choosing a scale to improvise over
Seeing which key the sounding chord belongs to narrows down the scales available to you.
Music theory terms explained
- Circle of fifths
- A circular diagram placing the twelve major keys a perfect fifth apart. **The way sharps and flats accumulate becomes visible as position.**
- Key signature
- The sharps or flats written at the head of the staff, indicating the key of the piece.
- Relative minor
- The minor key sharing a major key's signature. C major and A minor differ only in where the scale begins.
- Diatonic chords
- The seven chords built solely from the notes of a key's scale. **Upper-case roman numerals mark major chords, lower-case minor ones.**
- Enharmonic equivalents
- Notes such as F♯ and G♭, identical in sound but written two ways. In practice the spelling with fewer accidentals is preferred.
- Modulation
- Changing key partway through a piece. The closer two keys sit on the circle, the smoother the transition.
Frequently Asked Questions
Side Note — Why the Circle of Fifths Moves in Fifths
The circle of fifths is arranged so that each step moves up a perfect fifth (for example, from C to G) to reach the next key. A perfect fifth is a highly consonant interval with a frequency ratio close to 2:3, so neighboring keys on the circle share many common tones (and chords), which is the practical reason this arrangement became standard — modulating between adjacent keys tends to sound smooth rather than jarring.
Going clockwise around the circle once adds one sharp at each step, reaching a midpoint of 6 sharps (or equivalently 6 flats) at F# (or Gb); continuing further, the number of flats then decreases step by step until arriving back at C after 12 steps. This is the combined result of equal temperament dividing the octave into 12 equal semitones, and the near-mathematical coincidence that stacking twelve perfect fifths lands almost exactly back on the starting pitch (with a tiny discrepancy known as the Pythagorean comma).
The circle of fifths isn't just a memorization aid — it's a practical tool used in composition and arranging. The classic pop chord progression I-V-vi-IV (for example, C-G-Am-F in the key of C) is built from the primary triads of four adjacent keys on the circle, which helps visualize the underlying structure of a chord progression.