In this paper a Kalman filter type algorithm for estimating a calibration characteristic of measurement instruments is presented. That approach gives a rigorous derivation of a recurrent algorithm for estimating the parameters of the calibration curve with the incorporation of the errors in reproducing the inputs. A new approach has been proposed for the generation of stopping rule in calibration characteristics identification problem. The proposed stopping rule defines the coefficients estimation halt and makes possible to determine sufficient number of measurements to attain required accuracy of calculated estimates. As an example, the problem of calibration of a differential pressure gauge using standard pressure setting devices (piston gauges) is examined.