What is 1.8 inches to millimeters? The answer is that 1.8 inches equals 45.72 millimeters.
How to convert 1.8 inches to mm? We know that one inch is equal to 25.4 millimeters, so to convert 1.8 inches to millimeters, we must multiply the amount of centimeters by 25.4, which means that 1.8 inches is equal to 1.8 inches × 25.4 = 45.72 mm.
See also: How to convert 1.8 mm to inches.