Inches → MillimetersInches to Millimeters,
Inches to Millimeters,
instantly.
A live inches to mm converter with fraction support, a full conversion chart and an interactive ruler. Built for engineers, makers and craftsmen.1 in = 25.4 mm.
Millimeters
25.4
mmFraction
1"
Feet & inches
1"
Formula
1 × 25.4
Tip: click or drag on the ruler to set the value.
How to convert inches to mm
Multiply the inch value by 25.4 to get millimeters. To convert mm back to inches, divide by 25.4.
millimeters = inches × 25.4
inches = millimeters ÷ 25.4
inches = millimeters ÷ 25.4
Example: 5 in × 25.4 = 127 mm.
Quick reference
- 1 inch25.4 mm
- 1 foot (12 in)304.8 mm
- 1/2 inch12.7 mm
- 1/4 inch6.35 mm
- 1/8 inch3.175 mm
- 1/16 inch1.5875 mm
Popular inches → mm conversions
Inches to mm chart
Common inch fractions and whole inches with their millimeter equivalents.
| Inches | Millimeters | Centimeters | |
|---|---|---|---|
| 1/16" | 1.588 mm | 0.1588 cm | details → |
| 1/8" | 3.175 mm | 0.3175 cm | details → |
| 3/16" | 4.762 mm | 0.4762 cm | details → |
| 1/4" | 6.35 mm | 0.635 cm | details → |
| 5/16" | 7.938 mm | 0.7938 cm | details → |
| 3/8" | 9.525 mm | 0.9525 cm | details → |
| 7/16" | 11.112 mm | 1.1112 cm | details → |
| 1/2" | 12.7 mm | 1.27 cm | details → |
| 9/16" | 14.288 mm | 1.4288 cm | details → |
| 5/8" | 15.875 mm | 1.5875 cm | details → |
| 11/16" | 17.463 mm | 1.7463 cm | details → |
| 3/4" | 19.05 mm | 1.905 cm | details → |
| 13/16" | 20.638 mm | 2.0637 cm | details → |
| 7/8" | 22.225 mm | 2.2225 cm | details → |
| 15/16" | 23.813 mm | 2.3813 cm | details → |
| 1" | 25.4 mm | 2.54 cm | details → |
| 1 1/2" | 38.1 mm | 3.81 cm | details → |
| 2" | 50.8 mm | 5.08 cm | details → |
| 2 1/2" | 63.5 mm | 6.35 cm | details → |
| 3" | 76.2 mm | 7.62 cm | details → |
| 3 1/2" | 88.9 mm | 8.89 cm | details → |
| 4" | 101.6 mm | 10.16 cm | details → |
| 4 1/2" | 114.3 mm | 11.43 cm | details → |
| 5" | 127 mm | 12.7 cm | details → |
| 6" | 152.4 mm | 15.24 cm | details → |
| 7" | 177.8 mm | 17.78 cm | details → |
| 8" | 203.2 mm | 20.32 cm | details → |
| 9" | 228.6 mm | 22.86 cm | details → |
| 10" | 254 mm | 25.4 cm | details → |
| 11" | 279.4 mm | 27.94 cm | details → |
| 12" | 304.8 mm | 30.48 cm | details → |
| 18" | 457.2 mm | 45.72 cm | details → |
| 24" | 609.6 mm | 60.96 cm | details → |
| 36" | 914.4 mm | 91.44 cm | details → |
Inches to mm — FAQ
How do I convert inches to mm?
Multiply inches by 25.4. For example, 5 inches × 25.4 = 127 mm.
How many mm are in one inch?
Exactly 25.4 mm. A foot (12 inches) is 304.8 mm.
What is 2.5 inches in mm?
2.5 inches equals 63.5 mm (2.5 × 25.4).
How do I convert a fraction of an inch to mm?
Convert the fraction to a decimal first, then multiply by 25.4. For example, 3/4" = 0.75 × 25.4 = 19.05 mm. See the fraction chart for every 1/64.