Scale degree

In music theory, a scale degree refers to the position of a particular note on a scale relative to the tonic, the first and main note of the scale from which each octave is assumed to begin. The term is useful for indicating the size of intervals and chords, and whether they are major or minor.

Scale degrees can be applied to any musical scale; however, the concept is most commonly applied to scales in which a tonic is specified by definition, such as the 7-tone diatonic scales (e.g. the C-major scale C–D–E–F–G–A–B, in which C is the tonic). It is possible to assign a scale degree to the 12-tone chromatic scale, but this is of no effect as all notes have the same importance in that scale, as is its intended purpose.

The expression scale step is sometimes used synonymously with scale degree, but it may alternatively refer to the distance between between two successive scale degrees (see Steps and skips). The terms whole step and half step are commonly used as interval names. The number of scale degrees and the distance between them together define the scale they are in.

The degrees of the traditional major and minor scales may be identified several ways:

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