Converting from millimeters to inches, 8 millimeters (mm) is equal to 0.3150 inches. One millimeter is equivalent to 0.0394 inches.
To convert 8mm to inches, one simply multiplies 8 by 0.0394 inches to arrive at 0.3150 inches. Using conversion tables or factors, one can convert from inches to millimeters by knowing that one inch is equivalent to 25.40 millimeters and then multiplying the number of inches by that figure.
Conversion tables and charts are useful when converting from the metric to the Imperial system, especially in math. While the English developed the Imperial system many centuries ago, the French developed the metric system in 1670.