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An optical interferometric proximeter system (IPS) for measuring thrusts and im-pulse bits of pulsed electric thrusters, has been developed. Unlike existing thrust stands, the IPS-based version ofiers the advantage of a single system that can yield EMI-free, high accuracy (< 2 % error) thrust measurements within a very wide range of impulses (100 „N-s to above 10 N-s) covering the impulse range of all known pulsed plasma thrusters. In addition to pulsed applications, the IPS is theoretically shown to be capable of measuring steady-state thrust values as low as 20 „N. The IPS-based thrust stand relies on measuring the dynamic response of a swinging arm using a two-sensor laser interferometer, with <10 nm position accuracy for all frequencies. The wide application of the thrust stand is demon-strated with thrust measurements of an ablative pulsed plasma thruster (APPT) and a quasi-steady magnetoplasmadynamic thruster (MPDT). Subsequent to the work presented here, an IPS based thrust stand was permanently installed at the NASA Jet Propulsion Laboratory