Ellipse Perimeter Calculator

What is an Ellipse ?

An ellipse is a geometric shape that resembles a flattened circle. It is defined by two points called foci (plural of focus) and all points on the ellipse have the sum of the distances from the two foci constant. The longest diameter of an ellipse is called the major axis, and the shorter diameter is called the minor axis.

The perimeter of an ellipse, often referred to as its circumference, is not as straightforward to calculate as the perimeter of a circle. However, an approximate formula can be used:

C ≈ 2π √((a² + b²) / 2))

where:

• A is the perimeter of the square
• a is half of the length of the major axis
• b is half of the length of the minor axis

Keep in mind that a and b represent half of the lengths of their respective axes. If you have the full lengths of the major and minor axes, divide them by 2 before using them in the formula. Also, ensure that all measurements are in the same unit.