The following is a list of definitions relating to conversions between millimeters and inches.
What is a millimeter (mm)?A millimeter is a unit of Length or Distance in the Metric System. The symbol for millimeter is mm. There are 25.4 millimeters in an inch. The International spelling for this unit is millimetre.
What is an inch (in)?An inch is a unit of Length or Distance in both US Customary Units as well as the Imperial System. The symbol for inch is in or ". There are 0.03937008 inches in a millimeter.