🥚 Ellipsoid Volume Calculator

Calculate the volume of an ellipsoid from its three semi-axes

How to Use This Calculator

1

Enter Three Semi-Axes

Input the lengths of the three semi-axes (a, b, c) of the ellipsoid. These are half the lengths of the ellipsoid's three principal diameters.

2

Click Calculate

Press the "Calculate Volume" button to compute the ellipsoid volume using the formula V = (4/3)Ï€abc.

3

Review Result

View the calculated volume displayed in cubic units. The result includes the step-by-step calculation showing how the formula was applied.

Formula

V = (4/3) × π × a × b × c

Where a, b, and c are the three semi-axis lengths

Where:

  • V = volume of the ellipsoid
  • a = semi-axis length along the x-axis
  • b = semi-axis length along the y-axis
  • c = semi-axis length along the z-axis
  • Ï€ ≈ 3.14159

Special Cases:

  • Sphere: If a = b = c = r, then V = (4/3)Ï€r³
  • Prolate Spheroid: If a = b < c (rugby ball shape)
  • Oblate Spheroid: If a = b > c (discus shape, like Earth)

Example 1: Find the volume of an ellipsoid with semi-axes a = 3, b = 4, c = 5 units

V = (4/3) × π × 3 × 4 × 5

V = (4/3) × π × 60

V = 80π ≈ 251.33 units³

Example 2: Find the volume of a sphere with radius 7 units (a = b = c = 7)

V = (4/3) × π × 7 × 7 × 7

V = (4/3) × π × 343

V = (1372/3)π ≈ 1,436.76 units³

Example 3: Earth is an oblate spheroid with semi-axes approximately 6,378 km (equatorial) and 6,357 km (polar)

a = b = 6,378 km, c = 6,357 km

V = (4/3) × π × 6,378 × 6,378 × 6,357

V ≈ 1.083 × 10¹² km³

About Ellipsoid Volume Calculator

An ellipsoid is a three-dimensional shape that generalizes a sphere. While a sphere has all radii equal, an ellipsoid has three different semi-axis lengths (a, b, c) along three perpendicular axes. This calculator computes the volume of any ellipsoid using the formula V = (4/3)Ï€abc.

When to Use This Calculator

  • Geometry: Calculate volumes of ellipsoidal shapes in mathematical problems
  • Earth Sciences: Estimate volumes of planets, moons, or other celestial bodies
  • Engineering: Design ellipsoidal tanks, containers, or structures
  • Medicine: Calculate volumes of ellipsoidal organs or structures from medical imaging
  • Physics: Determine volume for ellipsoidal objects in fluid dynamics or mechanics
  • Architecture: Plan volumes for ellipsoidal architectural elements

Why Use Our Calculator?

  • ✅ Handles All Ellipsoids: Works for any ellipsoid shape (sphere, spheroid, or general ellipsoid)
  • ✅ Instant Results: Get accurate volume calculations immediately
  • ✅ Step-by-Step Display: See the formula applied with your values
  • ✅ 100% Accurate: Uses precise mathematical formulas
  • ✅ Educational: Helps understand ellipsoid geometry
  • ✅ Completely Free: No registration required

Types of Ellipsoids

Depending on the relationship between the three semi-axes, ellipsoids take different forms:

  • Sphere: a = b = c (all axes equal) - the most symmetric ellipsoid
  • Prolate Spheroid: a = b < c (rugby ball, elongated along one axis)
  • Oblate Spheroid: a = b > c (discus, flattened at the poles) - Earth is approximately this shape
  • General Ellipsoid: a ≠ b ≠ c (three different axes) - most general case

Real-World Applications

Planetary Science: Earth is approximately an oblate spheroid with equatorial radius 6,378 km and polar radius 6,357 km. Its volume is about 1.083 × 10¹² km³, calculated using the ellipsoid volume formula.

Medical Imaging: Calculate the volume of organs from MRI or CT scans. If an organ has semi-axes of 5 cm, 6 cm, and 4 cm, its volume is (4/3) × π × 5 × 6 × 4 ≈ 502.65 cm³.

Engineering: Design an ellipsoidal tank with semi-axes 2 m, 2 m, and 3 m. The volume is (4/3) × π × 2 × 2 × 3 = 16π ≈ 50.27 m³, useful for capacity planning.

Frequently Asked Questions

What is an ellipsoid?

An ellipsoid is a 3D shape that generalizes a sphere. While a sphere has equal radii in all directions, an ellipsoid has three different semi-axis lengths (a, b, c) along three perpendicular axes, creating an egg-like or rugby ball-like shape.

How is an ellipsoid different from a sphere?

A sphere is a special case of an ellipsoid where all three semi-axes are equal (a = b = c). An ellipsoid allows the three axes to be different, creating more varied shapes. The sphere volume formula V = (4/3)πr³ is a special case of the ellipsoid formula when a = b = c = r.

What are semi-axes?

Semi-axes are half the lengths of the ellipsoid's three principal diameters. If the full lengths along x, y, and z axes are 2a, 2b, and 2c, then a, b, and c are the semi-axes. They extend from the center to the surface.

Can I use this for a sphere?

Yes! If you enter the same value for all three semi-axes (a = b = c = radius), you'll get the sphere volume. For example, for a sphere of radius 5, enter a = 5, b = 5, c = 5.

What's the difference between a prolate and oblate spheroid?

A prolate spheroid has a = b < c (elongated like a rugby ball). An oblate spheroid has a = b > c (flattened like a discus). Earth is an oblate spheroid, slightly flattened at the poles.

How accurate is this calculator?

This calculator uses the exact mathematical formula V = (4/3)Ï€abc, providing precise results limited only by input accuracy and floating-point precision. For most practical purposes, results are accurate to many decimal places.