Square Millimeters to Square Inches Converter
How to convert square millimeters to square inches
square inches = square millimeters ÷ 645.16
To convert square millimeters to square inches, divide the number of square millimeters by 645.16.
1 mm² = 0.0015500031 in²
Examples
- One square centimeter: 100 mm² ÷ 645.16 = 0.15500031 in²
- 2.5 mm² ÷ 645.16 = 0.00387500775 in²
Square millimeters to square inches conversion table
| Square millimeters (mm²) | Square inches (in²) |
|---|---|
| 1 mm² | 0.0015500031 in² |
| 2 mm² | 0.0031000062 in² |
| 3 mm² | 0.0046500093 in² |
| 4 mm² | 0.0062000124 in² |
| 5 mm² | 0.0077500155 in² |
| 10 mm² | 0.015500031 in² |
| 15 mm² | 0.0232500465 in² |
| 20 mm² | 0.031000062 in² |
| 25 mm² | 0.0387500775 in² |
| 50 mm² | 0.077500155 in² |
| 75 mm² | 0.116250232 in² |
| 100 mm² | 0.15500031 in² |
| 200 mm² | 0.31000062 in² |
| 500 mm² | 0.77500155 in² |
| 1,000 mm² | 1.5500031 in² |
| 5,000 mm² | 7.7500155 in² |
| 10,000 mm² | 15.500031 in² |
Unit definitions
- Square millimeter (mm²)
- A square millimeter is one millionth of a square meter. It is the standard unit for the cross-sectional area of electrical wire and cable outside North America.
- Square inch (in²)
- A square inch is the area of a square with 1-inch sides, exactly 6.4516 square centimeters. It is used in the United States for small surfaces and appears in the pressure unit psi.