Major and minor scales

A scale is seven notes in order, from one note up to the next one with the same name. What makes it major or minor is not the notes but the distance between them: whole steps and half steps.

Whole steps and half steps

A half step (semitone) is the smallest distance on the piano: from one key to the very next, white or black. A whole step (tone) is two half steps.

Between almost every pair of white keys there is a black one, so from one white key to the next is a whole step. There are two exceptions, with no black key in between: E–F and B–C are a half step apart.

The major scale

Every major scale follows the same step formula: W W H W W W H (whole, whole, half, whole, whole, whole, half).

C major is the only one that uses just white keys: the half steps land right on E–F and B–C.

Where the key signature comes from

If you start the scale on G using only white keys, the formula breaks at the end: E to F is a half step and F to G a whole step, but the major scale needs the opposite. To fix it, F has to go up to F♯.

That F♯ is exactly the key signature of G major. Instead of writing it on every note, it goes once at the start of the staff. Every key has the key signature its scale needs to follow the formula. We explain it in full in the circle of fifths and key signatures.

The minor scale

The natural minor scale has a different formula: W H W W H W W. The half step comes earlier, between the second and third notes, and that is why it sounds sadder.

A minor is the minor scale that uses only white keys: the same notes as C major, but starting on A.

Harmonic minor and the leading tone

In the major scale, the seventh note is a half step below the tonic and "pulls" back to it. It is called the leading tone. In natural minor that note is a whole step away, and the return to the tonic sounds weaker.

That is why in minor-key music it is very common to raise the seventh by a half step. That version is called harmonic minor: in A minor, G becomes G♯. That accidental is not in the key signature, it is written note by note, and it is one of the best clues that a piece is in a minor key.

There is also melodic minor, which raises the sixth and seventh on the way up (F♯ and G♯ in A minor) so the melody flows without the big jump between F and G♯.

Relative and parallel keys

• Relative: same key signature, different tonic. C major and A minor use the same notes. The relative minor is 3 semitones below the major, on the sixth note of its scale.
• Parallel: same tonic, different key signature. C major has no sharps or flats; C minor has three flats (B♭, E♭, A♭).

Scale table

By Joaquin Varela · Updated November 1, 2026