Minor Scales, Scale Degrees, and Key Signatures

The natural minor scale follows the pattern W–H–W–W–H–W–W. Compared to the major scale, scale degrees 3̂, 6̂, and 7̂ are each lowered by a half step. The half steps in natural minor fall between 2–3 and 5–6. The result is a darker, more introspective sound. Every major key has a relative minor that shares the same key signature: the relative minor begins on scale degree 6̂ of its relative major (e.g., A minor is relative to C major).

Two additional minor scale forms address the weak leading tone of natural minor. The harmonic minor raises 7̂ by a half step, restoring the half-step pull to the tonic (pattern: W–H–W–W–H–A2–H, where A2 is an augmented second). The melodic minor raises both 6̂ and 7̂ when ascending (matching major from 5̂ upward) and reverts to natural minor when descending. These variants coexist in tonal music; the harmonic minor is especially common in harmony, while the melodic minor smooths out vocal lines.

Key signatures for minor keys are identical to those of their relative majors. To find the key signature for a minor key, locate its relative major (a minor third above the tonic) and use that signature. A minor uses no sharps or flats (relative to C major); E minor uses one sharp (F♯, relative to G major); D minor uses one flat (B♭, relative to F major). The parallel minor of a major key (same tonic, different signature) always has three more flats or three fewer sharps.