Justin Jacob Long (born June 2, 1978) is an American actor, known for his roles in Alvin and the Chipmunks, Dodgeball, Alpha and Omega, and Live Free or Die Hard.

He played the role of Kevin in Disney's 2005 film Herbie: Fully Loaded and Troop Leader Adam Devlin (uncredited) in the 2009 Disney comedy film Old Dogs.