What is the circle of fifths?

The circle of fifths is a diagram that arranges all 12 musical keys in a loop. Each adjacent key is a perfect fifth apart. Moving clockwise adds one sharp; moving counter-clockwise adds one flat. It is the most important reference tool in Western music theory.

What is a relative minor?

Every major key has a relative minor key that shares exactly the same notes and key signature. The relative minor starts on the 6th degree of the major scale (9 semitones up from the root). For example, A minor is the relative minor of C major.

Why do some keys have two names (e.g., F# and Gb)?

Enharmonic keys share the same pitches but are spelled differently using sharps or flats. F# major (6 sharps) and Gb major (6 flats) sound identical. Composers choose one spelling based on which is easier to read in context.

What are diatonic chords?

Diatonic chords are chords built entirely from the notes within a given key. A major key has seven diatonic chords: three major (I, IV, V), three minor (ii, iii, vi), and one diminished (vii°). These are the chords that naturally harmonize melodies in that key.

How do I use this for songwriting?

Click your desired key to see its diatonic chords. Build a chord progression using any combination of those chords — they are guaranteed to sound harmonious together. The I, IV, and V chords are the most stable anchors, while ii, iii, and vi add color and tension.

Circle of Fifths Tool

Name: Circle of Fifths Tool
Availability: InStock
Author: Nham Vu

Click any key on the interactive circle of fifths to instantly see its scale notes, key signature, relative minor, and common chords.

Circle of Fifths

Click any key segment to explore

Major key (outer) Minor key (inner) Selected key

Selected Key

C Major MAJOR

Key Signature

No sharps or flats

Relative Key

A minor

Scale Notes

Diatonic Chords

Copied!

Summary

Click any key on the interactive circle of fifths to instantly see its scale notes, key signature, relative minor, and common chords.

How it works

The SVG circle shows all 12 major keys in the outer ring and their relative minors in the inner ring.
Click any outer segment to select a major key, or any inner segment for a minor key.
The key panel on the right instantly shows the scale notes, key signature (sharps or flats), and relative minor.
The chord suggestions section lists the seven diatonic chords (I through VII) for the selected key.
Use the copy button to copy the scale notes to your clipboard for use in your DAW or sheet music.

Use cases

Find the scale notes for any major or minor key while composing or practicing.
Identify how many sharps or flats a key signature contains.
Discover the relative minor of any major key for emotional contrast in songwriting.
Look up diatonic chord suggestions to build chord progressions.
Understand which keys are closely related (adjacent on the circle share six notes).
Transpose a song by navigating to the target key and comparing notes.
Teach music theory students the relationship between keys visually.
Quickly reference enharmonic equivalents (e.g., F# major = Gb major).

Frequently Asked Questions

Last updated: 2026-07-01 · Reviewed by Nham Vu