A customizable diagnostic meter is provided. The diagnostic meter includes a meter (20) for performing a diagnostic test, wherein the meter (20) includes a housing (30) having a slot (40), and a module (50) having one or more functions. The slot (40) is configured to receive and removably secure at least a portion of the module (50). A customizable diagnostic meter kit including two or more modules (50) configured to be inserted in a meter (20) is also provided.