# Circular mils calculator

A circular mil represents the *area of a circle or conductor* that has a diameter of **1 mil**. Use this online converter to quickly convert **mils (mils)** to **circular mils (cmils)**.

In addition, you can also use the calculator to:

- convert mm to circular mils (cmils)
- convert inches to circular mils (cmils)
- convert feet to circular mils (cmils)

**How to use the calculator: **

Choose the unit you want to convert **from** – by selecting either *mils, mm, inches or feet* and specify the quantity. Hit calculate to get the equivalent in **circular mils (cmils)**!

### Mils to circular mils formula

To calculate circular mils, **c,** from mils, use the formula,** c= d²** where d is the diameter of the wire in mils.

For example, if the diameter of a conductor is 3 mils, then the circular mils equivalent is **3 x 3 = 9 circular mils (cmil). **You can work out circular mils from diameter in other units such as inches, mm and feet.

Similarly, you can use the converter above to workout the circular mils from equivalent diameters in either mm, inches or feet.

### Inches to circular mils formula

To workout circular mils from inches, we use the conversion, *1 inch = 1,000,000 circular mils*

### mm to circular mils formula

To workout circular mils from mm, we use the conversion, *1 mm = 39,370 circular mils*

### Feet to circular mils formula

To workout circular mils from feet, we use the conversion, *1 foot = 83,333.3 circular mils*

## Working with square mils

A square mil on the other hand is the area of a square whose sides are 1 mil.

### Square mils vs. circular mils

Now that we know what they are, we can easily get the equivalent area in circular mils from

square mils and vice versa.

#### Square mils to circular mils formula

To convert square mils to circular mils, use the formula: **1 circular mils = 1.27323 * square mils.**

#### Circular mils to square mils formula

To convert circular mils to the equivalent area in square mils, use the formula: **1 square mils = circular mils / 1.27323**