Square Centimeters to Square Miles
An instant square centimeters-to-square miles converter, with the formula and a reference table below.
| Square Centimeters | Square Miles |
|---|---|
| 1 cm² | 3.86102e-11 mi² |
| 2 cm² | 7.72204e-11 mi² |
| 3 cm² | 1.15831e-10 mi² |
| 5 cm² | 1.93051e-10 mi² |
| 10 cm² | 3.86102e-10 mi² |
| 25 cm² | 9.65255e-10 mi² |
| 50 cm² | 1.93051e-09 mi² |
| 100 cm² | 3.86102e-09 mi² |
How to use
- Enter a value in the Square Centimeters field.
- The Square Miles figure appears immediately — no button to press.
- Typing in the Square Miles field converts back to Square Centimeters the same way.
- Use the reference table for the values that come up most often.
Square Centimeters to Square Miles formula
The factor from square centimeters to square miles is 3.86102159e-11.
mi² = cm² × 3.86102159e-11
Why this factor: the square centimeter and the square mile are both defined against the square meter, so dividing one definition by the other gives 3.86102159e-11 directly. Both definitions are set out in full below.
To go the other way, divide by 3.86102159e-11 — or use the Square Miles to Square Centimeters converter, which is the same calculation reversed.
Worked example
Given 1000 cm², multiplying by 3.86102159e-11 yields 3.86102e-08 mi².
1000 cm² × 3.86102159e-11 = 3.86102e-08 mi²
The converter above does this for any value you type, in either direction.
What is a square centimeter?
A square centimeter is the area of a one-centimeter square.
Definition: Exactly 1×10⁻⁴ square meter — because 0.01 m squared is 0.0001 m².
Where it is used: Small surface areas, contact and cross-sectional areas, and pressure calculations.
What is a square mile?
A square mile is the area of a one-mile square, used for large land areas in the US and UK.
Definition: Exactly 2,589,988.110336 square meters, and exactly 640 acres.
Where it is used: County, state and metropolitan areas, and population density in the US.
Square Centimeters vs Square Miles
The square centimeter is a metric unit while the square mile is an imperial unit. That is why the factor between them is not a round number: the two systems were defined independently and only later tied together by exact agreement.
Frequently asked questions
How many square miles are in a square centimeter?
One square centimeter equals 3.86102159e-11 square miles.
What is the formula to convert square centimeters to square miles?
Multiply the number of square centimeters by 3.86102159e-11. To reverse it, divide by 3.86102159e-11 instead.
How do I convert square miles back to square centimeters?
Divide by 3.86102159e-11, which is the same as multiplying by 2.58998811e+10.
How many square miles are in 10 square centimeters?
10 cm² works out to 3.86102e-10 mi².
How is the square centimeter defined?
Exactly 1×10⁻⁴ square meter — because 0.01 m squared is 0.0001 m².