Convert 1/8 inches to millimeters

"Fractional Inches to Millimeters" Calculator
Convert
to Millimeters

How many millimeters in 1/8 inches?

Answer

1/8″ = 3.175 mm

= 0.125″ · decimal inches

Exact: 1″ = 25.4 mm by definition (1959), and a ruler fraction converts without rounding. If the thread is marked G 1/8 (BSPP), its basic outside diameter is 9.728 mm (ISO 228-1): the inch size of a pipe thread is nominal.

01/41/23/4105101520inmm1/8″3.175 mm

1 ÷ 8 = 0.125; 0.125 × 25.4 = 3.175 mm

Neighbouring sizes

Related Calculations

See Also

Recalculate with different values ↑

Fractional Inches to Millimeters Conversion Table

Fractional InchesMillimeters
1/16″1.5875 mm
1/8″3.175 mm
3/16″4.7625 mm
1/4″6.35 mm
5/16″7.9375 mm
3/8″9.525 mm
7/16″11.1125 mm
1/2″12.7 mm
9/16″14.2875 mm
5/8″15.875 mm
11/16″17.4625 mm
3/4″19.05 mm
13/16″20.6375 mm
7/8″22.225 mm
15/16″23.8125 mm
1″25.4 mm

FAQ

How many millimeters in 1/8 inches?

1/8″ = 3.175 mm

What is the formula to convert 1/8″ to millimeters?

The formula is: mm = (numerator ÷ denominator) × 25.4. For 1/8″: (1 ÷ 8) × 25.4 = 3.175 mm.

What is the nearest whole millimeter to 1/8″?

1/8″ = 3.175 mm; the nearest whole millimeter is 3 mm, 0.175 mm less.

See Also