He made his stage debut as Daddy Warbucks in a sixth-grade school production of the musical Annie. Afterwards, he co-starred in a satirical play written and cast by his future The Office co-star B.J. Novak when they were high school seniors.
Before entering college, Krasinki taught English as a foreign language in Costa Rica.
Krasinksi went to Brown University, studying theater arts under Lowry Marsh and John Emigh, and graduating in 2001 as a playwright with the honors thesis “Contents Under Pressure.”
During his time at Brown University, Krasinski was a member of the sketch comedy group Out of Bounds.
In college, Krasinski helped coach youth basketball at the Gordon School in East Providence, Rhode Island.