How often must a gage be calibrated? There are no set of rules or regulations that exist defining how often a gage needs to be calibrated. Ultimately, the frequency of gage calibration is up to the company or facility owner or manager. While some believe that annual calibration is a good rule to live by, there are resources at stake that must be considered. Calibrating one gage or multiple gages too often will waste a large amount of time and money. However, on the other hand, not calibrating a gage that needs it will result in poor accuracy. Calibration should definitely be done in regular intervals, but the definition of regular will vary based on the drift and use of a particular machine. Using historical trend analysis can help determine what gages require more frequent calibration and when to expect that they will need to be calibrated.