A calibration method, including steps of: providing a test meter having a socket provided with a set of conductive pins; providing a biosensor test strip having a set of strip electrodes corresponding to the set of conductive pins, wherein the combination of lengths of the strip electrodes corresponds to a parameter code; inserting the biosensor test strip into the socket of the test meter so that each of the conductive pins and each of the corresponding strip electrode have a relative motion; reading out the parameter code by using a set of pulse widths detected by each of the conductive pins in the insertion period; and calibrating the test meter by using the parameter code to match a calibration parameter installed in the test meter.