This application is a handy tool to help you spell chords properly, preserving thirds at all times. It's especially useful when dealing with double flats and double sharps. It also reveals the inherent patterns present in chord construction, which are sometimes overlooked in traditional theory methods. Just select the chord quality, then the desired root, to reveal the spelling. Seven chord types are here, the four basic triads major, minor, diminished, augmented, and the three most common 7th chords: dominant, minor 7, and major 7. A perfect companion for students and professionals.