In music theory, an augmented third is an interval that has five half steps 
The augmented third requires that:
- The interval must be a third interval (three note names between the first and the last).
- The interval must have five half steps.
What does an augmented third look like?
Here is an example of a melodic augmented third (two music notes in a melody) and a harmonic augmented third (in a chord):
How to recognize an augmented third?
Rule of music theory: All intervals in a major scale starting with the tonic (degree I) are either major or perfect, and only unison, octave, fourth and fifth are perfect (the others are major).
Example with the interval G♭ / B♮:
Let's take the G flat major scale to have G♭ as the tonic:
From the rule stated above, the interval G♭ / B♭ is a major third, so the intervall G♭ / B♮ is an augmented third.
Inversion of the augmented third
The inversion of the augmented third is the diminished sixth.
Here is an example of a diminished sixth:
Musical examples of augmented third
No examples yet, but feel free to send me some examples!
Interval identification game
You will find this interval in my Intervals identification game:
