A measurement device comprising: a first controller configured to output a control signal, the control signal designating both an input signal and a calibration signal of a plurality of calibration signals (CAL1, CAL2) to be converted into a digital input signal and a digital calibration signal, respectively, the input signal being input from an outside of the measurement device, the calibration signal (CAL1, CAL2) being previously prepared; and a second controller configured to perform a first control and then to perform a second control based on the control signal output from the first controller, the first control being for selecting the input signal and converting the selected input signal into the digital input signal, the second control being for selecting the calibration signal (CAL1, CAL2) and converting the selected calibration signal into the digital calibration signal; characterised in that the second control is for calculating a measured value using the digital input signal converted by the first control and another digital calibration signal converted by a control performed before the first control; the second controller comprises: a selector configured to select the input signal and one of the calibration signals; a converter configured to convert the input signal and the one of the calibration signals (CAL1 and CAL2) selected by the selector into the digital input signal and the digital calibration signal, respectively; and wherein the second controller is configured to perform the conversion of the calibration signal (CAL1, CAL2) into the digital calibration signal by the converter and the calculation of the measured value in parallel. a first controller configured to output a control signal, the control signal designating both an input signal and a calibration signal of a plurality of calibration signals (CAL1, CAL2) to be converted into a digital input signal and a digital calibration signal, respectively, the input signal being input from an outside of the measurement device, the calibration signal (CAL1, CAL2) being previously prepared; and a second controller configured to perform a first control and then to perform a second control based on the control signal output from the first controller, the first control being for selecting the input signal and converting the selected input signal into the digital input signal, the second control being for selecting the calibration signal (CAL1, CAL2) and converting the selected calibration signal into the digital calibration signal; characterised in that the second control is for calculating a measured value using the digital input signal converted by the first control and another digital calibration signal converted by a control performed before the first control; the second controller comprises: a selector configured to select the input signal and one of the calibration signals; a converter configured to convert the input signal and the one of the calibration signals (CAL1 and CAL2) selected by the selector into the digital input signal and the digital calibration signal, respectively; and wherein the second controller is configured to perform the conversion of the calibration signal (CAL1, CAL2) into the digital calibration signal by the converter and the calculation of the measured value in parallel. a selector configured to select the input signal and one of the calibration signals; a converter configured to convert the input signal and the one of the calibration signals (CAL1 and CAL2) selected by the selector into the digital input signal and the digital calibration signal, respectively; and wherein the second controller is configured to perform the conversion of the calibration signal (CAL1, CAL2) into the digital calibration signal by the converter and the calculation of the measured value in parallel.