When calibrating measuring instruments, the deviation (bias) of the instrument is determined. This can be done by directly comparing it with product specifications or through a series of comparisons with derived standards. Based on the calibration, it can be determined whether the instrument still meets its specifications. In calibration, it is important to obtain traceable values as much as possible (according to ISO standards). A demonstrably traceable calibration is obtained from accredited calibration facilities.

Calibrating a measuring instrument is the only way to ensure the accuracy, precision, and validity of results. When used as a tool for quality assurance, periodic calibration of equipment helps minimize costs related to errors caused by measurement inaccuracies or incorrect readings. Regular calibration is, therefore, a real source of savings.