Calculate the area and perimeter of a donut shape.
This calculator uses metres for measurements.
Donut = a circle with a smaller circle centred inside
A = ta-ti ta = 𝛑D² ti = 𝛑d² 𝛑 = 3.14159265 PO = 𝛑D PI = 𝛑d PO the outer perimeter of the donut PI the inner perimeter of the donut
one metre (m) = 3.28083989501312 feet (ft) one metre (m) = 39.3700787401575 inches (in) one square metre (m²) = 10.7639104167097 square feet (ft²) one square metre (m²) = 1550.0031000062 square inches (in²)