A plastic tolerance proofing tool adapted to be implemented with a computer system. The computer system includes a processor and a memory storing a CAD object of an apparatus to be manufactured with a material. The tool includes a criteria selector operable to prompt for and receive a type of plastic material for the apparatus to be manufactured in and an extractor operable to determine a nominal dimension and a related tolerance from the CAD object. The tool further includes a comparator operable to compare the tolerance with a first threshold and a second threshold, and a tagging module operable to tag the CAD object based on the comparisons.