Whole and half steps
The half step is the smallest distance in Western music and equals one fret on the guitar; a whole step is two.
Essential
Content under musical review. It may contain inaccuracies.
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The half step is the smallest distance in Western music and equals one fret on the guitar; a whole step is two.
Essential
The half step (or semitone) is the smallest distance between two notes in Western music. Two half steps make a whole step. On the guitar the math is simple: one fret = one half step and two frets = one whole step.
A half step sounds tight, almost like a rub:
A whole step leaves more room between the two notes:
And here are all twelve half steps of an octave in a row, the chromatic scale:
Natural notes are almost always a whole step apart, except for two pairs: E–F and B–C, which are a half step apart. On the fretboard you can see it because there's no empty fret between them:
String 6, Open: E2 · 3 · Third
| Pair | Distance | Frets |
|---|---|---|
| C–D | whole step | 2 |
| D–E | whole step | 2 |
| E–F | half step | 1 |
| F–G | whole step | 2 |
| G–A | whole step | 2 |
| A–B | whole step | 2 |
| B–C | half step | 1 |
Play the open sixth string (E) and climb one fret at a time up to the 12th. Say "half" at every step. Then start again, moving two frets at a time: now you're playing whole steps.
Compare a half step and a whole stepWhole and half steps are the building blocks of scales. The major scale always follows the same pattern from its tonic:
W – W – H – W – W – W – H
Starting on C, that pattern lands exactly on the natural notes, which is why C major has no sharps or flats. Start anywhere else and you'll need accidentals to keep the pattern.
On a single string you can play any scale by counting frets with that pattern. It's awkward for the hand, but perfect for seeing how the scale is built.
See the C major scalePlay G major on the third string, starting open: frets 0, 2, 4, 5, 7, 9, 11 and 12. The moves from fret 4 to 5 and from 11 to 12 are the pattern's two half steps. Then repeat it on the fifth string from open A.
Scales, arpeggios & fretboardScale sequencesPlay melodic patterns (thirds, groups…) to master the scale in one position.Not every half step is spelled the same way. From E to F is a diatonic half step (a minor second: the letter and the pitch both change). From F to F♯ is a chromatic half step (an augmented unison: same letter, different pitch). In equal temperament they sound identical; the spelling depends on function.
In equal temperament each half step multiplies the frequency by the twelfth root of 2, roughly 1.0595. Twelve half steps in a row double the frequency: an octave.