Area of an Ellipse Calculator
A = π × a × b, where a and b are the semi-major and semi-minor axes.
Result
Area
47.1239 units²
Eccentricity: 0.8000.
- Semi-major (a)5
- Semi-minor (b)3
- Circumference (Ramanujan)25.5270
- Area in terms of π15 π
Step-by-step
- Area = π × a × b = π × 5 × 3 = 47.1239.
How to use this calculator
- Enter the semi-major and semi-minor axes.
- Read area; circumference is shown for reference.
About this calculator
An ellipse generalizes the circle: instead of one radius, two semi-axes (a and b). The area formula is just πab — a clean generalization. Circumference is harder; Ramanujan's second approximation gives high accuracy for any aspect ratio.
Frequently asked
"Semi" means half — these are half the long and short diameters of the ellipse.
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