1 square inch = 6.4516 square centimetres
A square inch is exactly 6.4516 cm². Screen sizes, pressure ratings and small component areas convert through this factor.
Formula cm² = in² × 6.4516
Type in either field — the other updates on every keystroke. Need other units? Open the full area converter.
| Square inch | Square centimetre |
|---|---|
| 1 in² | 6.4516 cm² |
| 2 in² | 12.9032 cm² |
| 3 in² | 19.3548 cm² |
| 4 in² | 25.8064 cm² |
| 5 in² | 32.258 cm² |
| 10 in² | 64.516 cm² |
| 15 in² | 96.774 cm² |
| 20 in² | 129.032 cm² |
| 25 in² | 161.29 cm² |
| 50 in² | 322.58 cm² |
| 100 in² | 645.16 cm² |
| 500 in² | 3225.8 cm² |
| 1000 in² | 6451.6 cm² |
| Square centimetre | Square inch |
|---|---|
| 1 cm² | 0.155 in² |
| 2 cm² | 0.310001 in² |
| 3 cm² | 0.465001 in² |
| 4 cm² | 0.620001 in² |
| 5 cm² | 0.775002 in² |
| 10 cm² | 1.550003 in² |
| 15 cm² | 2.325005 in² |
| 20 cm² | 3.100006 in² |
| 25 cm² | 3.875008 in² |
| 50 cm² | 7.750016 in² |
| 100 cm² | 15.500031 in² |
| 500 cm² | 77.500155 in² |
| 1000 cm² | 155.00031 in² |
| Situation | From | To |
|---|---|---|
| One square inch | 1 in² | 6.452 cm² |
| Bank card | 7.16 in² | 46.19 cm² |
| Index card | 15 in² | 96.77 cm² |
| US letter page | 93.5 in² | 603.2 cm² |
| Square 10 in | 100 in² | 645.2 cm² |
| One square foot | 144 in² | 929 cm² |
Multiply by 6.5. 10 in² is about 65 cm², against an exact 64.5.
Screen, paper and component areas switch between square inches and square centimetres. A US letter page of 93.5 in² is 603.2 cm².
Area scales with the square of length, so use 6.4516, not 2.54. A 2 in square is 25.8 cm², not 5.08.
A square inch is exactly 6.4516 cm², because the international inch is exactly 2.54 cm.
One square inch is exactly 6.4516 cm² (2.54 squared). A US letter page of 93.5 in² is 603.2 cm².
Related guides: Imperial vs metric: differences and quick conversion tricks