The uncertainties calculation procedure for the estimation of errors when the fringe counting method is used to get the sensitivity of standard accelerometers is developed. The fringe counting method is used in the frequency range from 50 to 800 Hz and into a dynamic range from 20 to 100 m s[sup -2]. Also, the reference condition is set up at 160 Hz and 50 m s[sup -2], where the main objective is to get the lowest uncertainty between all the frequency and dynamic ranges mentioned above. This calculation procedure agrees with both the ``Guide to the expression of uncertainty in measurement'' and the ISO 5347-1 ``Primary vibration calibration by laser interferometry.'' Furthermore, type B uncertainties are received from specific technical information from the equipment used during the calibration procedure and the type A uncertainty is received from periodic measurements performed on the standard accelerometer which have been monitored. Data from primary calibrations have been used to validate the estimation of uncertainties. Moreover, this paper shows the differences on the levels of error sources involved in a standard accelerometer calibration.