How to convert square millimeters to square centimeters
cm² = mm² × 0.01Multiply the value in square millimeters by 0.01. To go the other way, multiply by 100 (or divide by 0.01).
A square millimeter is smaller than a square centimeter: it takes 100 square millimeters to make one square centimeter.
Worked examples
- 1 square millimeter1 mm² × 0.01 = 0.01 cm²
- 5 square millimeters5 mm² × 0.01 = 0.05 cm²
- 10 square millimeters10 mm² × 0.01 = 0.1 cm²
- 20 square millimeters20 mm² × 0.01 = 0.2 cm²
- 100 square millimeters100 mm² × 0.01 = 1 cm²
Square millimeters to square centimeters conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| Square millimeters (mm²) | Square centimeters (cm²) |
|---|---|
| 0.1 mm² | 0.001 cm² |
| 0.25 mm² | 0.0025 cm² |
| 0.5 mm² | 0.005 cm² |
| 1 mm² | 0.01 cm² |
| 2 mm² | 0.02 cm² |
| 3 mm² | 0.03 cm² |
| 4 mm² | 0.04 cm² |
| 5 mm² | 0.05 cm² |
| 6 mm² | 0.06 cm² |
| 7 mm² | 0.07 cm² |
| 8 mm² | 0.08 cm² |
| 9 mm² | 0.09 cm² |
| 10 mm² | 0.1 cm² |
| Square millimeters (mm²) | Square centimeters (cm²) |
|---|---|
| 12 mm² | 0.12 cm² |
| 15 mm² | 0.15 cm² |
| 20 mm² | 0.2 cm² |
| 25 mm² | 0.25 cm² |
| 30 mm² | 0.3 cm² |
| 40 mm² | 0.4 cm² |
| 50 mm² | 0.5 cm² |
| 75 mm² | 0.75 cm² |
| 100 mm² | 1 cm² |
| 250 mm² | 2.5 cm² |
| 500 mm² | 5 cm² |
| 1,000 mm² | 10 cm² |
About the units
Square millimeter (mm²)
Used for wire cross-sections in metric countries (e.g. 2.5 mm² cable). One square millimeter equals 0.000001 square meters (m²).
Square centimeter (cm²)
The square centimeter (cm²) is a unit of area in the International System of Units (SI). One square centimeter equals 0.0001 square meters (m²).
Frequently asked questions
How many square centimeters are in one square millimeter?
There are 0.01 square centimeters in one square millimeter, and this value is exact by definition.
How do I convert square millimeters to square centimeters?
Multiply the number of square millimeters by 0.01. For example, 10 mm² × 0.01 = 0.1 cm².
How many square millimeters are in one square centimeter?
One square centimeter equals 100 square millimeters. That is the reverse factor, 1 ÷ 0.01.
What is 10 square millimeters in square centimeters?
10 mm² = 0.1 cm².
Is this mm² to cm² converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.
Convert square millimeters to other units
- Square millimeters to square meters
- Square millimeters to square kilometers
- Square millimeters to hectares
- Square millimeters to square inches
- Square millimeters to square feet
- Square millimeters to square yards
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- Square millimeters to square miles