Shapes & spaces

Sphere cross-section radius at an offset calculator

Find the radius and area of the circular section made by a plane through a sphere.

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Behind the numbers

How this calculation works

Find the radius and area of the circular section made by a plane through a sphere.

THE FORMULAρ=√(R²−d²)

A worked example

At offset 3 in a sphere of radius 5, the section radius is 4.

Good to know

A plane farther away than the radius does not cut the sphere.

Read the result

Find the radius and area of the circular section made by a plane through a sphere.

The primary result is labeled “Section radius”. Keep the input definitions in view when comparing this result with another method.

Try a related calculation

A plane farther away than the radius does not cut the sphere.

For a related exercise, try the circle calculator.

A few questions, answered

How can I check the default inputs by hand?

At offset 3 in a sphere of radius 5, the section radius is 4.

Which rule does this calculator apply?

ρ=√(R²−d²)

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