Online calculator: Sphere

A sphere is the set of all points in three-dimensional space which are at distance r from a fixed point of that space, where r is a positive real number called the radius of the sphere. The sphere has the smallest surface area among all surfaces enclosing a given volume and it encloses the largest volume among all closed surfaces with a given surface area.

Volume formula: $4/3 \pi R^3$
Surface area formula: $4 \pi R^2$