He played college football for the Michigan State Spartans, and was selected by the Oakland Raiders in the third round in the 2016 NFL draft.

He was named a second team All-American by numerous publications and was a finalist for the Ted Hendricks Award.

He was expected to leave college and enter the 2015 NFL draft, but he returned to school for his senior year and, during the 2015 season, he collected 49 tackles (15 for a loss, including 10.5 sacks), 3 passes defensed, and a forced fumble.

[8][9] He played in 10 games as a rookie recording nine tackles and a pass defensed before being placed on injured reserve on December 23, 2016.

[10] On September 2, 2017, Calhoun was waived by the Raiders and was signed to the practice squad the next day.

[18] In Week 2 against the Seattle Seahawks on Sunday Night Football, Calhoun recorded his first career sack on Russell Wilson during the 35–30 loss.

[23] On October 19, 2021, Calhoun was signed to the Kansas City Chiefs practice squad.