In terms of chords and melody, Betsy on the Roof has complexity on par with the typical song, having near-average scores in Chord Complexity, Chord Progression Novelty and Chord-Bass Melody and below-average scores in Melodic Complexity and Chord-Melody Tension.
Betsy on the Roof is written in the key of D Dorian. According to the Theorytab database, it is the most popular key among Dorian keys and the 29th most popular among all keys. The D Dorian scale is similar to the D Minor scale except that its 6th note is a half step higher (B). Chord progressions in Dorian have a characteristic sound due to the major quality of the chord built on the 4th scale degree. See the D Dorian Cheat Sheet for popular chords, chord progressions, downloadable midi files and more!