Major second
The major second is a whole tone of two semitones, with a just ratio of 9:8, and it is the step between most neighbouring degrees of the major scale.
From C
- Size
- 2 semitones
- Abbreviation
- M2
- Just ratio
- 9:8 (203.91 cents)
- Equal-tempered
- 200 cents (−3.91 from just)
- Inversion
- Minor seventh
What it sounds like
The major second is a dissonance in tonal harmony, though a mild one. Its ratio, 9:8, is simple enough that the two notes sound less harsh than a minor second, yet they do not sound stable together. Melodically it is the basic step: it moves a line forward without leaving the key, and it sounds open and mobile. Harmonically it sounds slightly unsettled, and it appears mainly as an added tone or as a clash between a chord and a melody note. Five of the seven steps in the major scale are whole tones.
How to recognise it by ear
The first two notes of 'Frère Jacques' rise by a major second. The sound is open and mobile: the line moves forward without pulling hard toward a target. Without that tune, sing do to re in C, C up to D, and notice how the step lifts without leaning. Practice: sing the tonic, then the second degree, return to the tonic, and repeat until the step is recognised without naming it first.
Theory
The major second inverts to the minor seventh: the lower note moves up an octave, and the semitones add to twelve. Quality changes from major to minor. Triads and common seventh chords are built from thirds, so a second appears only in suspended and added-tone chords, such as the sus2 chord, where the second replaces the third. Its just ratio is 9:8, which measures 203.91 cents. The equal-tempered whole tone is 200 cents, so the just size is 3.91 cents wider.
The major second above every note
Spelled by letter name, so the interval’s number is always right: a major second above E♭ is not the same spelling as above D♯.
| From | To | Hear it |
|---|---|---|
On the piano
Further reading
- Reading Intervals at Sight: Generic and SpecificFundamentals · 6 min
- Ear Training for Intervals: A Method You Can Practise DailyEar Training & Practice · 7 min
- The Major Scale Formula: Whole and Half Steps ExplainedFundamentals · 7 min
Questions
Why does a major second sound stable in a melody but unsettled in a chord?
In a melody, the step is heard as motion within a key, and the ear accepts the tension because the line moves on. Stacked as a chord, the same two notes clash directly, and the ear hears friction between them. The interval is identical either way; context changes how the ear reads its function.
How many major seconds are in a major scale?
Five. The major scale follows the pattern whole, whole, half, whole, whole, whole, half, so five of its seven steps are major seconds and two are minor seconds. The minor seconds fall between the third and fourth degrees, and between the seventh and the octave.
How do I tell a major second from a minor second by ear?
Compare them by sound, not by counting keys. Sing a note, then the step a whole tone above it, then the step a half tone above it. The minor second sounds closer and rougher, while the major second sounds more open. Return to the starting note after each step and hear which one pulls back harder.