Music Theory for the 21st-Century Classroom

There are only two notes in an interval, one lower and one higher. To invert an interval, change the position of the notes so the note that was lower is now higher.

In the above example, a m6 inverts to a M3. This is true for all notes a M3 (or m6) away from each other. Below are examples of how intervals invert.

Note that the symbol \(\left.\text{}^{\circ}{}\right.\) represents “diminished” (one half step smaller than perfect or minor) and the symbol \(\left.\text{}{+}\right.\) represents “augmented” (one half step larger than perfect or major).

Below is a chart of how intervals invert.

To write a small interval below a given note, you should be able to combine whole steps and half steps up to the interval of a perfect fourth (two whole steps plus one half step). To write a larger interval below a given note, invert the interval size, determine the note above, then write it below the given note.