Eccentricity Calculator

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Calculate the eccentricity of conic sections like ellipses and hyperbolas.

Dimensions

Semi-major Axis (a)

Semi-minor Axis (b)

Eccentricity Result

0.8000

Eccentricity (e)

Eccentricity measures how much a conic section deviates from being circular.

Shape TypeEllipse

About this calculator

What is Eccentricity?

In mathematics, the eccentricity of a conic section is a non-negative real number that uniquely characterizes its shape. It measures how much the conic section deviates from being a perfect circle. A circle has an eccentricity of 0, an ellipse between 0 and 1, a parabola exactly 1, and a hyperbola greater than 1.

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Pro Tips

e = 0: Circle
0 < e < 1: Ellipse
e = 1: Parabola
e > 1: Hyperbola

Fun Facts

"The eccentricity of Earth's orbit is currently about 0.0167, making it nearly circular."
"The orbit of Pluto is much more eccentric, at about 0.248."
"Comets often have very high eccentricities, sometimes close to 1 (parabolic) or even greater (hyperbolic) if they are passing through only once."

Formula: e = c / a = √(1 - b²/a²) (for Ellipse)