Krasinski was born in the Brighton section of Boston, Massachusetts, the son of nurse Mary Clare (née Doyle) and internist Dr. Ronald Krasinski. He has two older brothers, Kevin and Paul, and was raised Catholic in the suburb of Newton, Massachusetts. He played on the same Little League Baseball team and attended the same high school as B.J. Novak, later his co-star (Ryan Howard) on The Office and also a writer and co-producer on episodes of the show. Krasinski graduated from Newton South High School in 1997. He was a camp counselor at Camp Chickami in Boston during his high school years. Before college, he took a semester off to teach English in Costa Rica. He went to Brown University, where he graduated in 2001 as a playwright, writing an honors thesis titled "Contents Under Pressure". During his time at Brown, he helped coach youth basketball as well as participated as a co-coordinator of the mid-year orientation. He then attended the National Theater Institute in Waterford, Con