Square inches to square centimeters
1 square inch = 6.4516 square centimeters
Type a value in square inches (sq in) to get square centimeters (cm²) straight away. A square inch is larger than a square centimeter, so the number goes up. Both units belong to area, measured here against the square meter.
1 sq in = 6.4516 cm²
Formula
cm² = sq in × 6.4516
One square inch is 6.4516 square centimeters, so multiply the square inch value by that factor. Here sq in is the value in square inches and cm² is the result in square centimeters.
Worked example: 50 square inches × 6.4516 = 322.58 square centimeters.
Square inches to square centimeters table
| square inches (sq in) | square centimeters (cm²) |
|---|---|
| 1 sq in | 6.4516 cm² |
| 2 sq in | 12.9032 cm² |
| 3 sq in | 19.3548 cm² |
| 4 sq in | 25.8064 cm² |
| 5 sq in | 32.258 cm² |
| 6 sq in | 38.7096 cm² |
| 7 sq in | 45.1612 cm² |
| 8 sq in | 51.6128 cm² |
| 9 sq in | 58.0644 cm² |
| 10 sq in | 64.516 cm² |
| 15 sq in | 96.774 cm² |
| 20 sq in | 129.032 cm² |
| 25 sq in | 161.29 cm² |
| 30 sq in | 193.548 cm² |
| 40 sq in | 258.064 cm² |
| 50 sq in | 322.58 cm² |
| 60 sq in | 387.096 cm² |
| 75 sq in | 483.87 cm² |
| 100 sq in | 645.16 cm² |
Everyday square inches in square centimeters
| What it is | sq in | cm² |
|---|---|---|
| a postage stamp (about) | 1 sq in | 6.4516 cm² |
| a 4 × 4 inch tile | 16 sq in | 103.226 cm² |
| a phone face (about) | 24 sq in | 154.838 cm² |
| a US letter sheet | 93.5 sq in | 603.225 cm² |
| one square foot | 144 sq in | 929.03 cm² |
Quick estimate in your head
Multiply by about 6.5. For 50 sq in that gives 325 cm² against an exact 322.58 cm², an error of 0.8%.
About the units
Square inch (sq in). A square 1 inch on each side, 6.4516 cm². Used for small surfaces and pressure units.
Square centimeter (cm²). A square 1 cm on each side. Used for small surfaces like tiles and paper.
Going the other way, 1 square centimeter is 0.155 square inches.
Questions
How many square centimeters are in 1 square inch?
1 square inch is 6.4516 square centimeters, and 1 square centimeter is 0.155 square inches.
How do I convert square inches to square centimeters?
Use cm² = sq in × 6.4516. For example, 50 square inches × 6.4516 = 322.58 square centimeters.
Is the square inch to square centimeter factor exact?
The factor comes from the unit definitions. Results here are rounded to 6 significant digits for display.
How much is one square foot in square centimeters?
144 sq in is 929.03 cm².
Source for the conversion factor: NIST Handbook 44, Appendix C (units of area).
Related conversions
- square centimeters to square inches
- square meters to square feet
- square feet to square meters
- square yards to square feet
- square feet to square yards
- gaj to square feet