Calibration is the process of configuring an instrument to provide a result for a sample within an acceptable range. The instrument can then provide more accurate results when samples of unknown values are tested in the normal usage of the product.

The process of making adjustments to certain numbers or components to get the best results from a circuit or program. In Arduino projects, this is often used when sensors in the real world may give different values in different circumstances, for instance the amount of light on a photoresistor. Calibration can be automatic or manual.