A data storage device is disclosed comprising a disk, a head comprising a laser, and a fly height actuator (FHA) configured to actuate the head vertically over the disk based on an FHA setting. A first fly height of the head is measured at a first laser power setting, and a second fly height of the head is measured at a second laser power. A FHA write setting is generated based on a calibrated write laser power, the first and second fly height measurements, and a first function representing a nominal FHA delta setting between a read touchdown FHA setting and a write touchdown FHA setting relative to a delta in a fly height of the head due to a corresponding change in laser power applied to the laser, where the FHA write setting is applied to the FHA during the write operation.