Use our simple sphere calculator to get any of the radius, diameter, area and volume of a sphere by entering one value in the form below.
How to use:
- Type a value in any one field (radius, diameter, surface area, or volume)
- The other three values will be calculated automatically as you type
- Clear a field to start with a different value
- Units are not displayed, remember that if the radius or the diameter are in unit u, the area will be in unit u2 and the volume in unit u3
Definition of a sphere
A sphere is the set of points in space that are at a distance r of a point called the center. This distance r is called the radius of the sphere.
Equation of a sphere
In a Cartesian coordinate system, the sphere with the centre at coordinates (a, b, c) and with radius r is the set of all points (x, y, z) such that:
r^2 = \left( x-a \right)^2 + \left( y-b \right)^2 + \left( z-c \right)^2Sphere formulas
Diameter and radius of a sphere
The diameter d of a sphere with respect to its radius r is d = 2r
Area of a sphere
The area A of a sphere can be calcuted from its radius r or its diameter d as A = 4πr² = πd²
Volume of a sphere
The volume V of a sphere can be calculated from its radius r or its diameter d as V = (4/3)πr³ = (1/6)πd³