A method to extract the complex permittivity of a dielectric material in a PCB is presented. The recessed probe launch allows striplines to be measured without the need of via transitions that are subject to large process variations. After pad parasitics are de-embedded using the two-line method, the complex permittivity of the dielectric is calculated from 20MHz to 5 GHz using closed-form equations. Internal inductance is taken into account to prevent overestimation of the permittivity at low frequency.