Square millimetres to Square inches Converter
Convert square millimetres (mm²) to square inches (sq in) instantly. Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet.
Result
- Square inches
- 0.00155 sq in
How to use the square millimetres to square inches converter
- Enter the square millimetres (mm²).
- The results update as you type, or press Calculate.
- Read the square inches first, then the supporting figures below it.
Formula
Square inches = square millimetres × 0.0015500031
Worked example
For example, with these inputs:
- Square millimetres (mm²): 1
the calculator returns:
- Square inches: 0.00155 sq in
Square millimetres to Square inches table
| Square millimetres | Square inches |
|---|---|
| 1 mm² | 0.00155 sq in |
| 2 mm² | 0.0031 sq in |
| 5 mm² | 0.00775 sq in |
| 10 mm² | 0.0155 sq in |
| 20 mm² | 0.031 sq in |
| 25 mm² | 0.03875 sq in |
| 50 mm² | 0.0775 sq in |
| 100 mm² | 0.155 sq in |
| 250 mm² | 0.387501 sq in |
| 500 mm² | 0.775002 sq in |
| 1,000 mm² | 1.55 sq in |
About this conversion
Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet.
Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Frequently asked questions
How many square inches are in one square millimetre?
1 mm² = 0.00155 sq in.
How do I convert mm² to sq in?
Square inches = square millimetres × 0.0015500031.