MM → Inches

8.25 mm to inches

8.25 millimeters equals 0.324803 inches — or about 5/16" (nearest 1/16″).

Decimal

0.3248 in

Fraction

5/16"

Centimeters

0.825 cm

Feet

0.0271 ft

mm
0.324803
in

5/16" (nearest 1/16)

1 in = 25.4 mm · tolerance ±0.0001

Formula

To convert mm to inches, divide by 25.4:

inches = mm ÷ 25.4
inches = 8.25 ÷ 25.4 = 0.324803

Why 8.25 mm = 0.3248 in

Since 1 inch is defined as exactly 25.4 millimeters, 8.25 mm converts to 0.324803 inches. Rounded to the nearest 1/16″ that's 5/16", which is what you'd read off a standard imperial ruler.