Justin was born July 11, 1970 in Springfield, Ohio. Chambers began has career as a model after begin discovered by a scout on the Paris subway. He went on to represent Calvin Klein in a fragrance campaign, and has worked all across Europe, Japan and the United States for both Calvin Klein and Armani.
After deciding to pursue an acting career, he moved to New York and studied at H.B. Studios for four years. That education landed him a few television roles, such as a recurring parts on Another World and New York Undercover. He went on to star several movies, including The Wedding Planner (2001) alongside Jennifer Lopez, and The Musketeer (2001) with Catherine Deneuve and Mena Suvari. Justin also had a recurring role on TV's "Cold Case."
Chambers is one of five children, including twin brother Jason. The twins were his parents' youngest. He met his wife, Keisha, a modeling agent, early in his career. The two have been married since 1993 and have five children of their own; Isabella (born 1997), twins Maya and Kaila (born 1999), Eva (born 2001) and Jackson (born 2003). He has a twin brother named Jason, one older brother and two older sisters.