Calibration is the comparison of a measurement instrument with another instrument or standard to detect, correlate, or eliminate by adjustment any inaccuracy.

Calibration is closely associated with Metrology.

Many quality programs require that test equipment calibrations provide traceability.

In the United States calibration standards are defined by NIST.

In Neurolinguistic Programming (NLP), calibration refers to the process of determining a person's internal state by observing their nonverbal behavior. Noticing a person's eye movements is one example of calibration. It is the ability to "read" a person. There are certain generalizations one can make about what a particular nonverbal event means, however NLP proposes that it is more important to notice what is going on with the person you are calibrating than with generalizations because there are always exceptions to the rule. For example, a lack of eye contact doesn't always mean that a person has something to hide, as is commonly believed.

Calibration exercise:

The following is a simple exercise to improve your calibration skills.

1. Find somebody you want to calibrate to
2. Ask them to think of something they like and notice any changes in their behavior (breathing patterns, eye movement, flushing, posture, etc.)
3. Ask them to think of something they dislike and notice any changes
4. Ask them to think of something neutral and notice any changes
5. Go back to step 2 and repeat until you know the differences
6. Name something and try to guess if they like it or not. If you get it right most of the time, congratulations! If not, go back to step 2 and practice some more. If you always get it wrong, try saying the opposite of what you think it is.

Once you have learned how to calibrate, you can begin to use anchors to condition certain responses, or you can do pacing and leading.

Cal`ibra"*tion (?), n.

The process of estimating the caliber a tube, as of a thermometer tube, in order to graduate it to a scale of degrees; also, more generally, the determination of the true value of the spaces in any graduated instrument.