Different manufacturers produce a trash can liner that "can fit" a specific gallon trash can, but the garbage bag could be a little large for a particular gallon trash can size. For example, a 38" X 39" trash bag is the correct size for a garbage can that is 32 gallons, but a 40" x 46" can liner also fits a 32-gallon garbage can, but you will waste 43% of the plastic. Another example is a 30" X 45" trash bag that will correctly fit a 23-gallon garbage can, while a 38" X58" will work too, but you will have a 63% waste increase. If you need help choosing the correct trash bag for your application, please get in touch with us today.