A positioning device configured to displace an object is disclosed. The positioning device comprises a stage to support the object, an actuator to move the stage with respect to a reference in a direction of movement, a balance mass arranged between the actuator and the reference to reduce transfer of reaction forces from the actuator to the reference, a support device arranged between the reference and the balance mass to support the balance mass, and a gravity compensator acting between the reference and the balance mass to exert a lifting force on the balance mass to reduce a gravitational support force to be provided by the support device to support the balance mass.