An integrated circuit (IC) die has an on-die parametric test module. A semiconductor substrate has die area, and a functional IC formed on an IC portion of the die area including a plurality of circuit elements configured for performing a circuit function. The on-die parametric test module is formed on the semiconductor substrate in a portion of the die area different from the IC portion. The on-die parametric test module includes a reference layout that provides at least one active reference MOS transistor, wherein the active reference MOS transistor has a reference spacing value for each of a plurality of context dependent effect parameters. A plurality of different variant layouts are included on the on-die parametric test module. Each variant layout provides at least one active variant MOS transistor that provides a variation with respect to the reference spacing value for at least one of the context dependent effect parameters.