Area / cm² → km²
Convert Square centimeters to Square kilometers
Convert surface areas in metric and international customary units. Convert Square centimeters (cm²) to Square kilometers (km²). Find the formula, worked examples, unit definitions, and practical guidance below.
Reverse: Square kilometers to Square centimeters →
How to convert square centimeters to square kilometers
Area factors are squared length factors. Acres here use international feet, not historical US survey feet.
Use x for the value in cm², b for the intermediate value in m², and y for the result in km².
km² = cm² × 0.0001 ÷ 1000000
Worked examples
10 cm² ≈ 1e-9 km²
Step 1: (10 × 0.0001) ≈ 0.001 m².
Step 2: 0.001 ÷ 1000000 ≈ 1e-9 km².20 cm² ≈ 2e-9 km²
Step 1: (20 × 0.0001) ≈ 0.002 m².
Step 2: 0.002 ÷ 1000000 ≈ 2e-9 km².
Results are rounded to 12 significant digits. Converting units does not increase the precision of the original measurement. Very large or small values outside JavaScript’s finite numeric range are rejected.
About Square centimeters
Square centimeters (cm²) measures area under the conventions above. The base value in m² is (x × 0.0001), where x is the numerical value in cm². Factors shown here are rounded for display; calculations use the stored factor.
About Square kilometers
Square kilometers (km²) measures area under the conventions above. The base value in m² is (x × 1000000), where x is the numerical value in km². Factors shown here are rounded for display; calculations use the stored factor.
Definitions and sources
Keep these unit conventions consistent when using measurements in construction calculations.
Square centimeters to square kilometers reference table
| Square centimeters (cm²) | Square kilometers (km²) |
|---|---|
| 1 | 1e-10 |
| 5 | 5e-10 |
| 10 | 1e-9 |
| 25 | 2.5e-9 |
| 50 | 5e-9 |
| 100 | 1e-8 |
| 1000 | 1e-7 |
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