How do I convert cm² to mm²?

Use the formula shown above or enter a value to see cm² converted to mm² instantly.

What is the formula for cm² to mm²?

The converter calculates mm² by applying the category-specific conversion factor for Area.

When should I use cm² vs mm²?

cm² and mm² are both part of the Area category; pick the unit that matches your measurement context (e.g., scale, region, or industry standard).

Area Converter & Surface Reference

Convert cm² to mm²

Use the live converter below to translate between Square Centimeter (cm²) and Square Millimeter (mm²). Scroll further for quick examples, formula tips, and related units.

Formula insight: Most unit conversions use a simple multiplication or division by a conversion factor. The calculator shows the exact formula used.

Convert

cm² → mm²

Square Centimeter

cm²

Square Millimeter

100

mm²

Rounded result (4 decimals max)

Formula

1 cm² = 100 mm²

Conversion sourcesTap or click to view references

The International System of Units (SI) — NIST Special Publication 330
National Institute of Standards and Technology (NIST). The SI Brochure (SP 330) is the definitive English edition of the BIPM SI tables. NIST’s edition lists the official constants and conversion factors tying inch-pound units to SI, which SwapUnits applies for length, mass, temperature, pressure, volume, and related conversions. See /standards/nist-si-tenfold for the complete decimal multiple/submultiple table. View source · View SI table

Results update as you type. Swap the direction to convert back from mm² to cm².

Back to main converter

cm² to mm² quick table

Multiply any row by the same factor to scale results. Use the converter above to enter exact values with your own units.

Square Centimeter (cm²)	Square Millimeter (mm²)
0.25 cm²	25 mm²
0.5 cm²	50 mm²
1 cm²	100 mm²
2 cm²	200 mm²
5 cm²	500 mm²
10 cm²	1,000 mm²
25 cm²	2,500 mm²
100 cm²	10,000 mm²

mm² back to cm²

Keep the reciprocal handy when double-checking calculations or undoing a conversion.

Square Millimeter (mm²)	Square Centimeter (cm²)
0.25 mm²	0.0025 cm²
0.5 mm²	0.005 cm²
1 mm²	0.01 cm²
2 mm²	0.02 cm²
5 mm²	0.05 cm²
10 mm²	0.1 cm²
25 mm²	0.25 cm²
100 mm²	1 cm²

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