A glass run installation tool for attaching a glass run to a door frame includes at least one lower abutment member and an upper abutment member. The tool also includes a base with a first arm and a second arm. The lower abutment member is coupled to the first arm, and the upper abutment member is coupled to the second arm. The second arm is moveable relative to the first arm between a clamped position and an unclamped position. The upper abutment member and the lower abutment member clamp the glass run and the door frame together to thereby attach the glass run to the door frame when the second arm is in the clamped position.