Considering the increasing frequency operating range of wireless devices (Smart-phones, WIFI box,..) and actual tendency to reduce emitting RF power, improved design procedures have to be considered for implementing efficient SAR probes. On one hand, the sensitivity is strongly related to the sensors itself (usually based upon low barrier Schottky diodes) and remains quite difficult to control while the up-raising frequency constraints tend to reduce the detecting area of the E-field sensors (for maintaining the local SAR estimation), and consequently the sensitivity. Another difficulty lies on the control of the isotropy of the probe, which is strongly dependent on the employed materials for realizing the probes. We propose in this paper a complete modeling procedure for directly extracting the isotropy performances of SAR probes, using 3D EM tools. The isotropy parameters to be experimentally determined are detailed first, and we present the extraction procedure implement through an hybrid analysis method combining –CST Microwave Studio™ and Matlab™ simulations. The results are compared with measurement on commercial probes.