Spherical Geometry Formulas & Solvers

Explore the complete family of spherical geometries. Compare equations, surface areas, and spatial volume calculations with instant interactive mathematical solvers.

Base Geometry 🌐

Complete Sphere

A perfectly symmetrical 3D round object where every exterior surface point is equidistant from the center point.

V = ⁴⁄₃ × π × r³
A = 4 × π × r²
  • Key Variable: Radius (\(r\)) or Diameter (\(d\))
  • Cross-section: Always a circle of radius \(r\)
  • Historical Proof: Archimedes 2:3 cylinder ratio
Launch Sphere Calculator →
Half Sphere 🌓

Hemisphere

Exactly half of a full sphere formed by a plane passing straight through the sphere's geometric center.

V = ²⁄₃ × π × r³
Total A = 3 × π × r²
  • Curved Surface Area: \(2\pi r^2\)
  • Flat Circular Base Area: \(\pi r^2\)
  • Real-Life: Architectural domes, bowls, igloos
Hemisphere Formula & Steps →
Segment 🧢

Spherical Cap (Segment)

The portion of a sphere cut off by any intersecting plane at height \(h\) from the pole.

V = ⅓ × π × h² × (3r − h)
Curved A = 2 × π × r × h
  • Parameters: Sphere radius (\(r\)), cap height (\(h\))
  • Cap Base Radius (\(a\)): \(a = \sqrt{h(2r - h)}\)
  • Applications: Fluid levels in partially filled tanks
Explore Cap Calculations →
Shell ⚪

Hollow Sphere (Spherical Shell)

The spatial region bounded between two concentric spheres with outer radius \(R\) and inner radius \(r\).

V = ⁴⁄₃ × π × (R³ − r³)
Total A = 4π(R² + r²)
  • Shell Wall Thickness (\(t\)): \(t = R - r\)
  • Outer Volume: \(\frac{4}{3}\pi R^3\)
  • Real-Life: Ball bearings, ping pong balls, pressure vessels
Shell Volume Solver →
Cone + Cap 🍦

Spherical Sector (Cone)

A solid formed by a spherical cap and the cone bounded by the sphere center and the cap's base boundary.

V = ²⁄₃ × π × r² × h
Total A = πr(2h + a)
  • Parameters: Sphere radius (\(r\)), cap height (\(h\))
  • Structure: Ice-cream cone shape
  • Calculus Proof: Polar coordinate triple integration
Review Sector Formula →
Stretched Sphere 🏉

Ellipsoid (Triaxial / Spheroid)

A 3D closed quadric surface that is the 3D analogue of an ellipse with semi-principal axes \(a\), \(b\), and \(c\).

V = ⁴⁄₃ × π × a × b × c
A ≈ 4π ((a^p b^p + ...)/3)^(1/p)
  • Special Case: When \(a = b = c = r\), \(V = \frac{4}{3}\pi r^3\)
  • Oblate Spheroid (\(a = b > c\)): Planet Earth shape
  • Prolate Spheroid (\(a = b < c\)): Rugby ball shape
Calculate Spheroid Volume →

Spherical Geometries Quick Comparison

Summary of volumetric equations and surface area expressions across all shapes.

3D Shape Volume Formula (\(V\)) Surface Area Formula (\(A\)) Required Variables
Sphere V = ⁴⁄₃πr³ A = 4πr² Radius \(r\)
Hemisphere V = ²⁄₃πr³ A = 3πr² (total) Radius \(r\)
Spherical Cap V = ⅓πh²(3r − h) A = 2πrh (curved) Radius \(r\), Height \(h\)
Spherical Shell V = ⁴⁄₃π(R³ − r³) A = 4π(R² + r²) Outer \(R\), Inner \(r\)
Spherical Sector V = ²⁄₃πr²h A = πr(2h + a) Radius \(r\), Height \(h\)
Ellipsoid V = ⁴⁄₃πabc Knudsen / Thomsen approx Semi-axes \(a, b, c\)
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Want to practice with worked geometry problems?

Check out our 20 solved math problems with radius, diameter, and real-world planetary and engineering examples.

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