Work out ellipse area instantly with clear inputs, formula shown and shareable results.
An ellipse is a circle stretched by a along one axis and b along the other, so its area is πab. When a = b it reduces to the circle area πr².
Ellipse area
A = π·a·b
Equal-area circle
r = √(ab)
Semi-axes. If you measured the full width and height, halve them first.
No. The perimeter needs an elliptic integral, which is why Ramanujan's approximation is used instead.