comprise measuring the true vibration with a laser doppler velocimeter ldv and vibrating the slider with arm electronics or electrostatic actuation the method may further comprise vibrating the slider at a p2 resonance mode in a frequency range of about 50 khz to 300 khz the fly height may be calibrated against the readback signal over the frequency range in other embodiments the invention also comprises a method of measuring a clearance between a disk and a slider including flying a slider above a magnetic media disk the slider having a head for reading data from the disk maintaining a fly height of the slider relative to the disk vibrating the slider such that the slider oscillates relative to the disk so that the slider contacts the disk detecting contact between the slider and the disk and detecting a mean to peak amplitude of the vibration at contact to determine the disk slider clearance in other embodiments the detecting step may comprise making a direct measurement with an ldv and or the vibrating step may comprise detecting contact with an arm electronics sensor mounted on the slider the method also may comprise converting a detected magnetic signal using a wallace spacing loss equation to a nanometer distance with a fly height correction the fly height correction may comprise the following steps flying a slider above a disk the slider.