Ellipse
Ellipse Formulas
Ellipse equation : `x^2 / a^2 + y^2 / b^2 = 1`
| a > b | a < b | |
|---|---|---|
| Semimajor axis | a | b |
| Semiminor axis | b | a |
| Major axis | 2a | 2b |
| Minor axis | 2b | 2a |
| Focal axis | x-axis | y-axis |
| Non focal axis | y-axis | x-axis |
| Center - Foci distance | `c = sqrt(a^2-b^2)` | `c = sqrt(b^2-a^2)` |
| Focal distance (FF') | 2c | 2c |
| Center - Vertex distance | a | b |
| Center - Co-vertex distance | b | a |
| Eccentricity | `e = c/a` | `e = c/b` |
| Center - Directrix distance | `d = a^2/c` | `d = b^2/c` |
| Area | `pi*a*b` | `pi*a*b` |
| Perimeter (Ramanujan approximation) |
`pi*(3*(a+b)` - `sqrt(10*a*b+3*(a^2+b^2)))` | |
See also
Conic section Equation calculator
Parabola calculator
Hyperbola calculator
Circle calculator
Conic sections calculators
Geometry calculators
Mathematics calculators