You have now learned that every key has its own key signature - from none at all in C major to several sharps or flats in other keys. There are many major and minor keys, with different key signatures and relative keys to keep track of.
The circle of fifths solves that problem. It arranges all the keys in a circle where every step in one direction adds a sharp, and every step in the other direction adds a flat. With the circle of fifths you don't need to memorize the keys one by one - you just need to understand the pattern, and then you can read off the rest.
What is a fifth?
A fifth is a distance between two notes. If you start on a note and count it as 1, the fifth note is a fifth up.
From C we count:
From C up to G is a perfect fifth. The distance is seven half steps.
This is the distance the circle of fifths is built on.
The circle of fifths
In the circle of fifths, the keys are arranged by their root notes. The keys' root notes are a fifth apart from each other around the circle. At the top is C major - the key with no key signature.
Clockwise you go a fifth up. Counterclockwise you go a fifth down.
Going clockwise from C, the keys come in fifths:
C → G → D → A → E → B …
Every step adds a new sharp. G major has one sharp, D major has two sharps and A major has three sharps.
Going counterclockwise from C, the same thing happens with flats:
C → F → B♭ → E♭ → A♭ …
F major has one flat, B♭ major has two flats and E♭ major has three flats.
Try it yourself: Click on the keys in the circle and see how the accidentals change as you go around it.
The outer ring shows major keys with capital letters. The ring inside shows relative minor keys with lowercase letters. So C and a mean C major and A minor.
The outer ring shows major keys (capital letters). The ring inside shows their relative minor keys (lowercase letters) - for example C major and A minor.
Relative keys in the circle of fifths
In the previous part you learned that a major key and a minor key can be relative keys - they contain the same notes and therefore the same key signature. In the circle of fifths this is visible right away: relative keys sit in the same position, just in different rings.
C major
A minor
G major
E minor
F major
D minor
So if you want to find the relative key of a major key, it's enough to look straight in toward the center from the major key in the outer ring.
How should you use the circle of fifths?
You don't need to memorize the whole circle at once. Instead, use it as a map you can look up, and it's a good idea to learn the most common keys first:
- C major and A minor have no key signature.
- G major and E minor have one sharp: F♯.
- D major and B minor have two sharps: F♯ and C♯.
- F major and D minor have one flat: B♭.
Every step away from C adds one key signature accidental. Clockwise it becomes sharps, counterclockwise it becomes flats.
Test yourself
1. D major is two steps clockwise from C in the circle of fifths. What does that tell you about the number of sharps in D major?
Show answer
Answer: D major has two sharps: F♯ and C♯. Every step clockwise adds one more sharp.
2. A key has three flats. Which major key is it, and what is the name of its relative minor key?
Show answer
Answer: E♭ major (three flats: B♭, E♭, A♭). Its relative minor key is C minor.
3. If you go one step counterclockwise in the circle of fifths from C, which key do you land on - and what key signature does it get?
Show answer
Answer: F major, with one flat: B♭.
4. Why are C and a in the same position in the circle of fifths - just in different rings?
Show answer
Answer: Because C major and A minor are relative keys. They contain the same notes and therefore have the same key signature (none at all).
Practice
Try recognizing keys from their key signatures in an interactive exercise.
Practice keys and key signaturesRemember
- The circle of fifths arranges keys by their root notes. The root notes are a fifth apart from each other.
- C major, with no key signature, sits at the top.
- Clockwise, the keys get more sharps. They are added in the order F♯, C♯, G♯, D♯, A♯, E♯, B♯.
- Counterclockwise, the keys get more flats. The flats are added in the order B♭, E♭, A♭, D♭, G♭, C♭, F♭.
- The inner ring shows each major key's relative minor key.
- You don't need to memorize the whole circle - use it as a map when you want to look up a key's key signature.
Well done!
You have gone through the entire Scales and Keys course - from whole steps and half steps to the circle of fifths!
Take the final test to check yourself on scales, keys and the circle of fifths.