What is 1 inches to millimeters? The answer is that 1 inches equals 25.4 millimeters.
How to convert 1 inches to mm? We know that one inch is equal to 25.4 millimeters, so to convert 1 inches to millimeters, we must multiply the amount of centimeters by 25.4, which means that 1 inches is equal to 1 inches × 25.4 = 25.4 mm.
See also: How to convert 1 mm to inches.