If you are a musician or a music enthusiast, you might have heard the term “interval” being used frequently. But what exactly are intervals in music theory?

And how do you work them out? In this tutorial, we will delve into the basics of intervals and provide you with a step-by-step guide on how to work them out.

Understanding Intervals in Music Theory

In simple terms, an interval is the distance between two notes. It defines the relationship between two pitches or tones and determines the melodic and harmonic structure of a piece of music.

There are two types of intervals – melodic and harmonic intervals. Melodic intervals refer to the distance between two notes played sequentially, while harmonic intervals refer to the distance between two notes played simultaneously.

Measuring Intervals

Intervals are measured by counting the number of letter names and accidentals (sharps or flats) between two notes. The distance is counted inclusively, meaning that both starting and ending notes are included in the count.

For example, if you want to measure the interval between C and E on a keyboard, you count up from C to D (1), then from D to E (2). Therefore, C to E is a 3rd interval.

Naming Intervals

Intervals are named according to their size (the number of letter names it spans) and quality (the number of accidentals it contains). The size of an interval can range from 1st to 8th (also known as an octave), with each size having its own name – unison for 1st, second for 2nd, third for 3rd, and so on.

The quality of an interval can be major, minor, perfect, augmented or diminished. A perfect interval has no alteration to its size or quality while major intervals have one more letter name than a perfect interval. Minor intervals have one less letter name than a major interval.

For example, the interval C to E is a third because it spans three letter names – C, D, and E. It is also a major third because it has two whole steps or four half-steps (C to D is a whole step, D to E is another whole step).

Working Out Intervals

To work out intervals, follow these simple steps:

  1. Identify the two notes you want to measure the interval between.
  2. Count the number of notes between them inclusively (including both starting and ending notes).
  3. Determine the size of the interval by naming it according to its number of letter names.
  4. Determine the quality of the interval by identifying its number of half-steps or whole steps.

For example, let’s say you want to work out the interval between A and F#. Count up from A to B (1), from B to C# (2), from C# to D (3), from D to E (4), from E to F# (5).

Therefore, A to F# is a 5th interval. Because it has seven half-steps or three-and-a-half whole steps, it is a diminished fifth.


In conclusion, intervals are an essential part of music theory that helps define the relationship between different pitches in music. By understanding how intervals are measured and named, you can work out any interval with ease. With practice and patience, working with intervals will become second nature and enhance your understanding and appreciation of music.