A method and system for measuring slider body clearance in a hard disk drive using positive and negative electrical pulses. In one embodiment, at least one positive direct current (DC) pulse is applied between a slider body and a hard disk of the hard disk drive. Furthermore, at least one negative direct current (DC) pulse is applied between the slider body and the hard disk. A contact potential voltage between said slider body and said hard disk is then determined in response to applying the at least one positive direct current (DC) pulse and the at least one negative direct current (DC) pulse.