How to Convert Square centimetres to Square inches (cm² to sq in)
Area conversions are everyday maths in Singapore property: HDB flats are listed in square metres while condo listings and PSF prices use square feet. This guide shows how to convert square centimetres into square inches by hand, with examples and a quick-reference table.
The conversion
To convert square centimetres to square inches, multiply the value by 0.15500031. To go the other way, divide by the same number (or multiply by 6.4516). For a quick estimate, multiply by about 0.16.
Square inches = square centimetres × 0.15500031
Worked examples
- 3 cm² = 0.465001 sq in
- 12.5 cm² = 1.9375 sq in
- 75 cm² = 11.625 sq in
Square centimetres to Square inches table
| Square centimetres | Square inches |
|---|---|
| 1 cm² | 0.155 sq in |
| 2 cm² | 0.310001 sq in |
| 5 cm² | 0.775002 sq in |
| 10 cm² | 1.55 sq in |
| 20 cm² | 3.1 sq in |
| 25 cm² | 3.875 sq in |
| 50 cm² | 7.75 sq in |
| 100 cm² | 15.5 sq in |
| 250 cm² | 38.7501 sq in |
| 500 cm² | 77.5002 sq in |
| 1,000 cm² | 155.0003 sq in |
Common questions
Is cm² to sq in exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Square inches to Square centimetres converter.
Mistakes to avoid
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
Singapore adopted the metric system in the 1970s, replacing imperial units and traditional Chinese measures in most official uses. Metric units are now standard in schools, trade and government, but older units survive in property, markets and imported goods.
For any value, use the Square centimetres to Square inches Converter or browse all area converters.
Run your own numbers: Square centimetres to Square inches Converter