A warpage test system uses a calibration block to calibrate the warpage test system over a temperature profile. The calibration block includes a first metal block bonded to a second metal block. The first metal block includes a first metal and a second different metal. The first metal block includes a CTE different than a CTE of the second metal block. The calibration block is disposed in the warpage test system. A warpage of the calibration block is measured over a temperature profile ranging from 28° C. to 260° C. A deviation between the measured warpage of the calibration block and a known thermal expansion of the calibration block over the temperature profile is recorded. The warpage measurement in a semiconductor package is compensated by the deviation between the measured warpage of the calibration block and the known thermal expansion or warpage of the calibration block over the temperature profile.