HomeUnit Conversion › Square inches to Square centimeters

Square inches to Square centimeters (in² to cm²)

Convert square inches to square centimeters: 1 in² = 6.4516 cm². Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

Formula

1 in² = 6.4516 cm²

square centimeters = square inches × 6.4516 — reverse: square inches = square centimeters × 0.15500031

The factor is derived from the SI definitions of both units (base unit: m2) as listed in NIST SP 811; results on this page are shown to 6 significant figures, the API returns up to 12.

Worked examples

Square inches to square centimeters conversion table

Square inches (in²)Square centimeters (cm²)
16.4516
212.9032
319.3548
425.8064
532.258
638.7096
745.1612
851.6128
958.0644
1064.516
1596.774
20129.032
25161.29
30193.548
40258.064
50322.58
75483.87
100645.16
2001290.32
2501612.9
5003225.8
10006451.6

FAQ

How many square centimeters are in one square inch?

1 in² = 6.4516 cm². The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

What is the formula to convert square inches to square centimeters?

Multiply the value in square inches by 6.4516: square centimeters = square inches × 6.4516. For example, 5 in² = 32.258 cm².

How do I convert square centimeters back to square inches?

Multiply by the inverse factor 0.15500031 (square inches = square centimeters × 0.15500031), or use the square centimeters-to-square inches page.

Related conversions

Machine access

Sources