A method of distance evaluation of a machine tool from an electrically conductive workpiece, wherein a capacitive sensing electrode is fixed by a holder on the machine tool, which is moved towards a workpiece by a drive device, wherein a processing electronics reads out a resonance frequency of an oscillating circuit, non-linearly dependent on the distance of the sensing electrode from the workpiece, wherein the sensing electrode is connected to the input of the oscillating circuit by a selectable impedance circuit, wherein • in the initial calibration when the endpoint of the machine tool touches the workpiece, the value of offset x 0 of the sensing electrode to the workpiece is determined; the value of the resonance frequency f m or the period T m of oscillation of difference frequency of the oscillating circuit is read-out when touching the workpiece; and a first and then a second calibration movements are carried out in one direction with reading out the corresponding values of the resonance frequency f m or the period of oscillation T m of difference frequency of the oscillating circuit; • each readout value of the oscillating circuit frequency f m is transformed into the value of the absolute distance of the sensing electrode from the workpiece by applying a linearizing function of the processing electronics, which is determined by three parameters of balanced setting, that are the gain K, the low limit frequency f 0 and the upper limit frequency f r of the oscillating circuit, or the gain K, the upper limit frequency f r of the oscillating circuit and the period T 0 of oscillation of difference frequency, and • the distance of the endpoint of the machine tools from the workpiece is defined by the value of the absolute distance of the sensing electrode from the workpiece and by the offset x 0 of the sensing electrode to the endpoint of the machine tool, while the offset x 0 is measured in the initial calibration, and characterised in that • in the initial calibration, the low limit frequency f 0 or the period T 0 of oscillation of difference frequency as a parameter of balanced setting of the linearizing function of the processing electronics is measured in the conductive connection of the sensing electrode with the workpiece, by means of a contact of the selectable impedance circuit controlled by a two-value selected electrical signal, wherein the sensing electrode is connected to the input of the oscillating circuit via a serially connected capacitor of the selectable impedance circuit, wherein the selectable impedance circuit includes a contact controlled by the two-value electrical signal generated by the processing electronics for setting the sensing electrode into contact with a workpiece during the calibration and an element of overvoltage protection connected in parallel to the controlled contact, wherein the output of this contact is connected to the input of the sensing electrode and the second output of the contact is connected to the potential of the workpiece, and wherein the active state of the selectable impedance is characterized by a contact switched on. • in the initial calibration when the endpoint of the machine tool touches the workpiece, the value of offset x 0 of the sensing electrode to the workpiece is determined; the value of the resonance frequency f m or the period T m of oscillation of difference frequency of the oscillating circuit is read-out when touching the workpiece; and a first and then a second calibration movements are carried out in one direction with reading out the corresponding values of the resonance frequency f m or the period of oscillation T m of difference frequency of the oscillating circuit; • each readout value of the oscillating circuit frequency f m is transformed into the value of the absolute distance of the sensing electrode from the workpiece by applying a linearizing function of the processing electronics, which is determined by three parameters of balanced setting, that are the gain K, the low limit frequency f 0 and the upper limit frequency f r of the oscillating circuit, or the gain K, the upper limit frequency f r of the oscillating circuit and the period T 0 of oscillation of difference frequency, and • the distance of the endpoint of the machine tools from the workpiece is defined by the value of the absolute distance of the sensing electrode from the workpiece and by the offset x 0 of the sensing electrode to the endpoint of the machine tool, while the offset x 0 is measured in the initial calibration, and • in the initial calibration, the low limit frequency f 0 or the period T 0 of oscillation of difference frequency as a parameter of balanced setting of the linearizing function of the processing electronics is measured in the conductive connection of the sensing electrode with the workpiece, by means of a contact of the selectable impedance circuit controlled by a two-value selected electrical signal, wherein the sensing electrode is connected to the input of the oscillating circuit via a serially connected capacitor of the selectable impedance circuit, wherein the selectable impedance circuit includes a contact controlled by the two-value electrical signal generated by the processing electronics for setting the sensing electrode into contact with a workpiece during the calibration and an element of overvoltage protection connected in parallel to the controlled contact, wherein the output of this contact is connected to the input of the sensing electrode and the second output of the contact is connected to the potential of the workpiece, and wherein the active state of the selectable impedance is characterized by a contact switched on.