Maths & numbers

Spherical cap calculator

Calculate the volume, base radius and surface areas of a sphere cut by a plane.

Spherical cap calculator
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A clear answer. Here’s how.

Requires cap height between zero and twice the sphere radius. Base radius = √[h(2R−h)], cap volume = πh²(R−h/3), curved area = 2πRh, and the closing disc area = πh(2R−h). At h=R this is a hemisphere; at h=2R it is a whole sphere. Uses one consistent length unit.

See a worked example

Worked example

A fixed demonstration, separate from the values you enter above.

Sphere radius
5
Cap height
2

Example result

Cap volume
54.4542726622
Base radius
4
Curved surface area
62.8318530718
Closing disc area
50.2654824574
Closed total surface area
113.097335529