Circle of Fifths — Interactive Music Theory Tool
Click any key on the circle to explore its chords, key signature, and relative minor. Play chords, build progressions, and understand how keys relate to each other — all in your browser.
Click any key to explore
Select a key from the circle
to see its chords and signature
Click chords above to add them. Then press Play to hear your progression.
Build a progression above, then export it as a .mid file — open directly in GarageBand, Logic, Ableton, or any DAW.
Frequently Asked Questions
What is the circle of fifths?
The circle of fifths is a diagram that arranges all 12 musical keys in a clock-like circle. Moving clockwise, each key is a perfect fifth (7 semitones) higher than the previous one. The circle shows how keys relate to each other — neighbouring keys share almost all their notes, making chord progressions between them sound natural. It was first described by Johann David Heinichen in 1711 and is one of the most useful reference tools in Western music theory.
Why is it called the circle of "fifths"?
Each step clockwise is a musical interval called a perfect fifth. A fifth means the 5th note of a major scale — from C, count up: C D E F G. G is a fifth above C. From G, the fifth is D. From D, it is A — and so on all the way around the circle back to C. The pattern cycles through all 12 notes, which is why it forms a complete circle.
What are sharps and flats in the key signature?
A key signature tells musicians which notes to always play sharp (♯, raised by a semitone) or flat (♭, lowered by a semitone) throughout a piece. C major has none — it uses only white keys on a piano. Moving clockwise adds one sharp per step (G = 1 sharp: F♯). Moving anticlockwise adds one flat per step (F = 1 flat: B♭). The maximum is 7 sharps or 7 flats before the key wraps back around enharmonically.
What is a relative minor?
Every major key has a relative minor that uses the exact same notes — just starting from a different root. The relative minor is always the 6th note of the major scale. C major uses the notes C D E F G A B. Starting that same sequence from A gives you A minor — same notes, different mood. On the circle, the relative minor appears on the inner ring directly alongside its major counterpart.
What is a parallel minor?
A parallel minor shares the same root note as its major key but uses different notes. C major and C minor both start on C, but C minor lowers the 3rd, 6th, and 7th notes, giving it a darker sound. Unlike the relative minor, the parallel minor has a different key signature. Composers often switch between parallel major and minor for emotional contrast — Beethoven and Schubert did this frequently.
What are diatonic chords?
Diatonic chords are the seven chords built entirely from the notes of a given key — no outside notes. In C major these are: C major (I), D minor (ii), E minor (iii), F major (IV), G major (V), A minor (vi), and B diminished (vii°). Roman numerals show each chord's position. Uppercase = major, lowercase = minor. The I, IV, and V chords are the three most common in Western music and appear in thousands of songs.
What is the I – V – vi – IV progression?
This is the most common chord progression in popular music. In C major it is: C – G – Am – F. You can hear it in hundreds of songs across rock, pop, and country. The progression works because V (G) creates tension that resolves to I (C), while vi (Am) adds an emotional touch and IV (F) provides a sense of departure before returning to I. It works in any key — just select a key and click the Pop preset to hear it.
What are enharmonic keys?
Enharmonic keys sound identical but are written differently. F♯ major and G♭ major use the same pitches on a piano — every note is the same frequency — but they are notated with different names. On the circle these appear at the bottom (6 o'clock position). Composers choose one spelling based on which is easier to read — F♯ major has 6 sharps, G♭ major has 6 flats, and musicians will usually prefer the key with fewer accidentals for their instrument.
How do I use the circle of fifths for songwriting?
Start by picking a key — say C major. The two keys immediately next to it (G and F) are your closest relatives and your chords will blend seamlessly when you move between them. The diatonic chords shown for your key are your "safe" palette — any combination will sound musical. For tension and drama, borrow a chord from the parallel minor or from a key across the circle. The progression builder on this page lets you experiment with all of these ideas by ear.
🎼 All Keys Reference Table
All 12 major keys with key signature, sharps/flats, relative minor, and parallel minor.
| Key | Sharps / Flats | Notes altered | Relative minor | Parallel minor | Enharmonic |
|---|
📖 How to read the circle
🟢 Outer ring — major keys
The 12 major keys arranged clockwise in fifths. C is at the top. Each clockwise step adds one sharp. Each anticlockwise step adds one flat.
🟣 Inner ring — relative minors
Each inner segment is the relative minor of the major key outside it. They share the same key signature and the same seven notes.
⬛ Highlighted segments
When you click a key, the selected key glows and its two neighbours are highlighted — these are the most closely related keys for writing chord progressions.
🔵 Enharmonic zone
The bottom three keys (B/C♭, F♯/G♭, D♭/C♯) are enharmonic — they sound identical but are written differently. Both spellings are shown.
🎸 Famous songs and their keys
Recognising which key a song is in helps you understand why certain chords appear together. Here are well-known songs and their home keys — click the key name to explore its chords.
| Song | Artist | Key | Progression |
|---|---|---|---|
| Let It Be | The Beatles | C major | I – V – vi – IV |
| No Woman No Cry | Bob Marley | C major | I – V – vi – IV |
| Someone Like You | Adele | A major | I – V – vi – IV |
| Sweet Home Chicago | Robert Johnson | E major | I – IV – V (blues) |
| Autumn Leaves | Jazz standard | G major | ii – V – I cycle |
| Stairway to Heaven | Led Zeppelin | A minor | i descending |
🎹 Using the circle of fifths for songwriting
Step 1 — Pick your home key
Click any key on the circle. That is your tonic — the chord your song will feel pulled back to. C major is the easiest for beginners (no sharps or flats). G major (1 sharp) is popular for guitar. D major (2 sharps) is common in country and folk.
Step 2 — Use your diatonic chords
The seven chords shown in the panel are all you need for most songs. The I chord is home, the V chord creates tension, the IV chord gives lift, and the vi chord adds emotion. Almost every pop song uses these four alone.
Step 3 — Borrow from neighbours
The two keys immediately left and right of yours on the circle share six of seven notes. Borrowing a chord from a neighbouring key — especially the IV of the neighbour — creates a sophisticated sound without feeling jarring. This is called a "pivot chord" modulation.
Step 4 — Switch to the relative minor for contrast
The inner ring shows your relative minor. Starting a verse in the major key and a chorus in the relative minor (or vice versa) is one of the most effective songwriting tools. The notes are identical — only the root changes, completely shifting the mood.
Step 5 — Try borrowed chords from the parallel minor
The parallel minor badge (shown when you select a key) points to a darker version of your key. The ♭VII and ♭VI chords from the parallel minor are frequently "borrowed" into major key songs for drama — you can hear this in rock and film scores constantly.
📚 References & Notes
- •Circle of fifths layout follows standard Western music theory convention (C at top, clockwise = adding sharps)
- •Key signature ordering follows the standard sequence: F♯ C♯ G♯ D♯ A♯ E♯ B♯ (sharps) / B♭ E♭ A♭ D♭ G♭ C♭ F♭ (flats)
- •Chord voicings use root position triads (root, 3rd, 5th) with a bass octave doubling
- •First described systematically by Johann David Heinichen in Der General-Bass in der Composition (1728)
This is an educational reference tool for music students and composers.