Merry Christmas, Darling by Glee Cast is in A at 80 beats per minute and runs 3:03 across 60 bars. It uses 29 chords — Bm7, Amaj7, F#m7, E7sus, E7, A, E, F#m, 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? Merry Christmas, Darling guitar melody tab.