[9] At age 12, Dort began playing organized basketball in Park Extension, a neighbourhood in Montreal, where he was coached by Nelson Ossé.

[11] Through his high school years, he competed for Brookwood Elite on the Amateur Athletic Union (AAU) circuit.

[13][14] As a sophomore, Dort transferred to Arlington Country Day School in Jacksonville, Florida to face better competition and learn English.

[14][15] Later in the month, he was invited to the Nike Americas Team Camp, where he was named most valuable player (MVP) of the All-Star game.

[16] Dort moved to Conrad Academy in Orlando, Florida for his junior season, following his former Arlington Country Day coach Shaun Wiseman.

[19] On October 18, 2017, he committed to play college basketball for Arizona State, becoming the program's most touted recruit since James Harden in 2007.

[30] Following Arizona State's loss in the 2019 NCAA men's basketball tournament, Dort announced his intention to forgo his final three seasons of collegiate eligibility and declare for the 2019 NBA draft.

[32] He made his NBA debut on December 6, 2019, playing 7 minutes and grabbing one rebound in an overtime win against the Minnesota Timberwolves.

On January 29, 2020, Dort scored a then career-high 23 points with two rebounds, a steal and a block in a 120–100 win over the Sacramento Kings.

[41][42] On November 3, 2023, Dort led the Thunder in scoring with 29 points while making all six of his three-point attempts, during a 141–139 loss to the Golden State Warriors.