There is not a standard-sized gasket to fit all Maytag washer doors. The gasket needed to stop a washer from leaking depends on the washer model.
Maytag washers have model numbers in one of three places: inside the washer lid, behind the control panel or on the back of the base frame. Once the model number is located, a replacement gasket can be ordered for the specific washer model from Maytag.com or one of many repair websites such as Repairclinic.com. Replacing a gasket is ranked as a do-it-yourself project by Repairclinic.com, meaning it requires some disassembling of parts, and experience in repair is helpful but not required. With the correct replacement gasket, leaking should stop.