Various parallax-free indicator devices, systems, and methods are disclosed. The indicator device may have a housing defining an aperture and a light source assembly at least partially disposed in the housing. The housing may be selectively securable via a fastener to an instrument in a selected orientation relative to the instrument. The light source assembly may have a light source operably coupled to a power source via a power circuit. The light source may be positioned within the housing to emit through the housing aperture. Upon activation, the light source assembly emits a parallax-free alignment indicator along an alignment axis that may have at least one of a selected angle and a selected displacement relative to a selected reference axis. The alignment indicator may guide a surgical procedure.