How to Convert 8mm to Inches
8 mm ÷ 25.4 = 0.3150 inches. To find the nearest 32nd, multiply by 32: 0.3150 × 32 = 10.08, which rounds to 10/32.
On a Tape Measure
Standard US tape measures show marks at every 1/16 inch. The nearest mark to 8mm is the 5/16″ mark. For rough layout work, use the 3/8″ mark.