Whole Steps, Half Steps, and Major Scales

By the end of this lesson, you will be able to distinguish whole steps from half steps on the keyboard and use the exact W–W–H–W–W–W–H formula to build three major scales: C D E F G A B, G A B C D E F♯, and F G A B♭ C D E.

Count distance by adjacent keys

A half step is the distance from one key to the nearest neighboring key, regardless of color. E–F and B–C are half steps even though both pairs use white keys. C–C♯ is also a half step. Key color helps you navigate, but it does not define the distance.

A whole step equals two half steps. From C to D, the path is C–C♯ and then C♯–D. From E to F♯, it is E–F and then F–F♯. Touch each adjacent key while checking a distance. This prevents the common assumption that every pair of neighboring white notes is a whole step. The compact international formula is W–W–H–W–W–W–H.

Build a scale in seven steps

A major scale travels from a tonic to the same note name in the next octave. Its seven distances are whole–whole–half–whole–whole–whole–half. Beginning on C produces C–D–E–F–G–A–B–C. The half steps fall between E–F and B–C.

Beginning on G gives G–A–B–C–D–E for the first six letter names. The sixth interval must be a whole step from E, so the next pitch is F♯, not F. F♯–G then supplies the final half step. Beginning on F gives F–G–A, and the third interval must be a half step. A–B is too wide, so lower B to B♭. A–B♭ is the needed half step.

Pitch spelling and keyboard location are different questions

A black key may have more than one written name. The key between F and G can be F♯ or G♭, but G major uses F♯ so the sequence contains each letter name G A B C D E F exactly once. F major likewise uses B♭, not A♯, so its letter sequence remains F G A B C D E.

This spelling rule does not claim that F♯ and G♭ occupy different keys on a modern piano. Keep two questions separate: “Which key do I press?” and “How is this pitch spelled in the current key?” Both answers matter.

Exercise

Three original scale-building cards

Draw three rows of eight boxes. Put the tonic in the first and last boxes, then fill in the letter names before checking distances.

1. C card: C–D–E–F–G–A–B–C. Write W, W, H, W, W, W, H under the gaps; circle E–F and B–C.
2. G card: G–A–B–C–D–E–F♯–G. Circle B–C and F♯–G; mark F♯ as the black key.
3. F card: F–G–A–B♭–C–D–E–F. Circle A–B♭ and E–F; mark B♭ as the black key.

Play each card with one finger so your attention stays on pitch. Say “whole step” or “half step” before every next note. If the formula conflicts with the letter sequence, stop at that gap. You probably skipped a letter or chose the wrong accidental.

Finally, cover the answers and rebuild all three scales from C, G, and F. You have learned the process when distance leads you to the altered note, rather than memory alone telling you that G has F♯ and F has B♭.

Common mistakes

• Symptom: Every white-key pair is called a whole step. Correction: Check E–F and B–C by looking for the nearest adjacent key.
• Symptom: G major is spelled G A B C D E G♭. Correction: Keep each letter name once; scale degree seven must be some kind of F, so write F♯.
• Symptom: F major uses A♯ instead of B♭. Correction: Write F G A B C D E first, then apply the flat to B.

Frequently asked questions

Why is E–F a half step when there is no black key between them? Half steps are defined by adjacent keys. There is no key of either color between E and F.

Are F♯ and G♭ the same key? On a modern piano, they use the same physical key in this context. The scale's function and letter sequence determine the spelling.

Must I memorize all three scales before I play them? Build them accurately first, then let checked repetition create memory. Do not replace the formula with guesses based on key color.