Inches → MM

1 inches to mm

1 inches equals 25.4 millimeters.

Millimeters

25.4 mm

Centimeters

2.54 cm

Meters

0.0254 m

Feet

0.0833 ft

Inches (in)

Millimeters (mm)

25.4

1 in = 25.4 mm · tolerance ±0.0001

Nearby values

0.98″0.94″0.9″1.1″1.125″0.87″0.86″1.18″0.8″1.2″

Precision

Inches

25.4 mm · max 100

Ref · 25.4 mm/in

Drag to set

Formula

mm = inches × 25.4
mm = 1 × 25.4 = 25.4

Why 1 in = 25.4 mm

The international inch is defined as exactly 25.4 mm, so any inches-to-mm conversion is a clean multiplication with no rounding required at this precision.