Augmented third
| Inverse | diminished sixth |
|---|---|
| Name | |
| Other names | - |
| Abbreviation | A3 |
| Size | |
| Semitones | 5 |
| Interval class | 5 |
| Just interval | 125:96, 21:16, 64:49 |
| Cents | |
| 12-Tone equal temperament | 500 |
| 24-Tone equal temperament | 500 |
| Just intonation | 457 |
In classical music from Western culture, an augmented third (ⓘ) is an interval of five semitones. It may be produced by widening a major third by a chromatic semitone. For instance, the interval from C to E is a major third, four semitones wide, and both the intervals from C♭ to E, and from C to E♯ are augmented thirds, spanning five semitones. Being augmented, it is considered a dissonant interval.
Its inversion is the diminished sixth, and its enharmonic equivalent is the perfect fourth.
The just augmented third, E♯, is 456.99 cents or 125:96. ⓘ The Pythagorean augmented third, E♯+++, is 521.51 cents or 177147:131072, eleven just perfect fifths. ⓘ