# Sphere area

## Area

Area is a numerical characteristic of a two-dimensional (flat or curved) geometric figure, informally speaking, showing the size of this figure. Historically, the calculation of the area was called quadrature. A figure having an area is called quadratic. Find the area of more than 22 shapes (triangle, square, pentagon, etc.) using our amazing calculator.

## Sphere

Sphere — a closed surface, all points of which are equally distant from one point (the center of the sphere). A segment connecting the center of a sphere with any point of it (as well as its length) is called the radius of the sphere.

## Sphere area

The area of a sphere is calculated by the formula S = 4πr². This identity is proved similarly to the area of a circle when a polyhedron is described around a sphere, the number of faces of which tends to infinity, and the size (area) of these faces, on the contrary, tends to zero. Then the total surface area of the polyhedron is as close as possible in value to the surface area of the sphere and equated to the product of pi by the four radii of the sphere squared.

- Area
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