Mad by Ne-Yo is in C at 66 beats per minute and runs 3:24 across 53 bars. It uses 9 chords — C, G, Dm, F, Dm7, Am, Am7, D7, and a few more. The chord diagram changes as the song plays and the words light up as they are sung, so you can strum and sing along without reading ahead.
Want the melody line note by note? Mad guitar melody tab.