Mahan Mj completed his studies at St. Xavier's Collegiate School, Calcutta, till Class 12th. He then went to IIT Kanpur after securing an All India Rank (AIR) of 67 in the Joint Entrance Examination.
Mahan Mj later joined the Ph.D. program in mathematics at the University of California, Berkeley. After earning a doctorate from UC Berkeley in 1997, he worked briefly at the Institute of Mathematical Sciences, Chennai in 1998.