Diminished sixth

Diminished sixth
Inverse	augmented third
Name
Other names	-
Abbreviation	d6
Size
Semitones	7
Interval class	5
Just interval	192:125, 32:21,49:32
Cents
Equal temperament	700
24-Tone equal temperament	700
Just intonation	743

In classical music from Western culture, a diminished sixth (Play^ⓘ) is an interval produced by narrowing a minor sixth by a chromatic semitone. For example, the interval from A to F is a minor sixth, eight semitones wide, and both the intervals from A♯ to F, and from A to F♭ are diminished sixths, spanning seven semitones.

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Being diminished, it is considered a dissonant interval, despite being equivalent to an interval known for its consonance. Its inversion is the augmented third, and its enharmonic equivalent is the perfect fifth.