Square millimeters to square centimeters
Type a value in square millimeters to see it in square centimeters straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the square millimeters box.
- Read the result in square centimeters as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
cm² = mm² × 0.01
Multiply the value in square millimeters by 0.01 to get square centimeters.
Example
To convert 25 mm² to square centimeters: 25 × 0.01 = 0.25 cm².
Conversion table
| Square millimeters (mm²) | Square centimeters (cm²) |
|---|---|
| 1 | 0.01 |
| 2 | 0.02 |
| 3 | 0.03 |
| 5 | 0.05 |
| 10 | 0.1 |
| 20 | 0.2 |
| 25 | 0.25 |
| 50 | 0.5 |
| 100 | 1 |
| 250 | 2.5 |
| 500 | 5 |
| 1,000 | 10 |
About the units
- Square millimeter
- A square millimeter is one millionth of a square meter, used for electrical cable cross sections.
- Square centimeter
- A square centimeter is exactly 0.0001 square meter, the area of a square with 1 cm sides.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many square centimeters are in one square millimeter?
1 mm² = 0.01 cm² exactly.
How do I convert square millimeters to square centimeters?
Use cm² = mm² × 0.01. For example, 25 mm² = 0.25 cm².
How many square millimeters are in one square centimeter?
1 cm² = 100 mm².
How do I convert square meters to square feet?
Divide the square meters by 0.09290304, or multiply by about 10.7639. The factor is exact because a foot is exactly 0.3048 m.
Are the dunam, feddan and acre the same size?
No. A metric dunam is 1000 m², an Iraqi dunam 2500 m², an Egyptian feddan about 4200.83 m² and an acre 4046.8564224 m².