An alignment tool for alignment of a scope mounted to a rail of a firearm is disclosed herein. In various aspects, the alignment tool includes a support removably securable to a rail of a firearm, and a laser line generator adjustably positionably attached to the support. The laser line generator may project a line having a known geometric relationship to the rail, and a reticle of the scope mounted to the rail may be aligned with the line. Related methods of use are disclosed herein.