Circular Mil
A circular mil is a unit of area used mainly to measure the cross-sectional area of round wires and cables in electrical engineering.
Defined as the area of a circle with a diameter of 1 mil (1 mil = 0.001 inch).
Area = (diameter in mils)² circular mils.
1 circular mil ≈ 7.854 × 10⁻¹⁰ square meters or 0.7854 square mils.
Circular mils simplify calculations for round wires since area scales with the square of the diameter.
Square Inch [in²]
A square inch (in²) is a unit of area representing a square with sides 1 inch long. It is commonly used in the United States for measuring small surfaces, such as paper sizes or screen dimensions.
1 square inch = 6.4516 square centimeters = 0.00064516 square meters.