A procedure for calculating the complex susceptibility, χ = χ -jχ , of granular superconductors with any given field and position dependent critical-current density J c is introduced. As an example of its application, the field-amplitude, H m , dependent χ of a sintered and oxidized YBa 2 Cu 3 O 7 - δ superconductor before and after air annealing at temperature T a = 150-550°C is measured and fitted by the calculated curves. The results show that with increasing T a , the intergranular J c decreases quickly between 150 and 250°C and above 450°C. The decreased J c is strongly position dependent, being greater at the center than on the surface. However, the fitting is never perfect; after χ versus H m is well fitted, the measured χ is always greater than the calculated one.