GUITAR THEORY AND EAR TRAINING
Guitar Chord Calculator

Guitar chord calculator.
(Will open in new window so you
can still read instructions below.)
This chord trainer lets you practice spelling chords in terms of the classical Roman numeral system of chord notation used in music schools. This has everything, including spellings for those dastardly Neapolitan chords, borrowed chords, secondary dominants, and secondary leading tone chords!
Note: this will only be useful for those who have previous experience and understanding of the Roman numeral system of notation.
Highly recommended by Douglas Niedt for frying your brain.