Method for measuring the mean frequency of a digital signal (S DP, S DI) which is derived from a reference periodic signal (S PR) generated by an oscillator forming an electronic time base of a timepiece, this timepiece comprising a movement incorporating a mechanism formed by a kinematic chain which is arranged between a motor device of the movement and an analogue time display device, this kinematic chain comprising or being kinematically linked to a continuous rotation electromagnetic transducer whose mean rotational speed is regulated by a regulation device, associated with the electronic time base, according to a nominal rotational speed, this regulation device being arranged to successively supply the electromagnetic transducer with regulation impulses (BP n) to regulate the mean rotational speed thereof, these regulation impulses defining respectively same events (tf n) which are synchronised on the rising edges or on the falling edges of said digital signal and which are detectable, by a measurement device without galvanic contact with the movement, at respective detection times having the same time phase-shift with said same events; the measurement method comprising the following steps: A) Measurement, without galvanic contact with the movement, of a plurality of successive time intervals (TI n) each occurring between two detection times which are detected for two respective regulation impulses among said regulation impulses; B) Determination, for each time interval of the plurality of time intervals, of a corresponding whole number (M n (S DP), M n (S DI)) which is equal to the rounded result (NR n (S DP), NR n (S DI)), to the nearest integer, of the division of this time interval by the theoretical mean period (PT DP, PMT DI) given by said digital signal; C) Summation of the whole numbers determined in step B) for the plurality of time intervals, to thus obtain a total number of periods of said digital signal; D) Summation of the measured time intervals of the plurality of time intervals, to thus obtain a total measurement duration (T Mes) corresponding to said total number of periods; E) Calculation of the mean frequency of said digital signal by dividing the total number of periods by said total measurement duration. A) Measurement, without galvanic contact with the movement, of a plurality of successive time intervals (TI n) each occurring between two detection times which are detected for two respective regulation impulses among said regulation impulses; B) Determination, for each time interval of the plurality of time intervals, of a corresponding whole number (M n (S DP), M n (S DI)) which is equal to the rounded result (NR n (S DP), NR n (S DI)), to the nearest integer, of the division of this time interval by the theoretical mean period (PT DP, PMT DI) given by said digital signal; C) Summation of the whole numbers determined in step B) for the plurality of time intervals, to thus obtain a total number of periods of said digital signal; D) Summation of the measured time intervals of the plurality of time intervals, to thus obtain a total measurement duration (T Mes) corresponding to said total number of periods; E) Calculation of the mean frequency of said digital signal by dividing the total number of periods by said total measurement duration.