Abstract: A method of calibrating a test platform for microwave packages is provided. According to the invention, the conventional Thru, Reflect and Line standard patterns are replaced by microwave standard packages fulfilling similar functions, the test platform being adapted accordingly. The use of standard packages makes it possible to retain the same electrical interface between each of the packages and the test platform. The invention also relates to a method of determining an electrical length LC of an etched line linking two microwave feeds of a microwave standard package. The standard package may be connected to the test platform. According to the invention, various electrical lengths of the test platform are measured so as to be able to deduce therefrom the electrical length LC of the etched line of the standard package. The invention exhibits the advantage of obtaining the electrical length LC by measurement rather than by modeling.