What is the volume of a cone?

The volume of a cone is one third times pi times the radius squared times the height. It is exactly a third of a cylinder with the same base and height. Enter the radius and height and the calculator works it out.

What is the slant height?

The slant height is the distance from the edge of the base to the tip along the surface. It is the square root of the radius squared plus the height squared, by Pythagoras, and is used for the surface area.

How do I find the surface area of a cone?

The total surface area is pi times the radius times the slant height, plus pi times the radius squared for the base. The calculator includes the base in the figure it shows.

Cone Volume Calculator

Work out the volume of a cone from its radius and height. Enter both and the calculator shows the volume, the slant height, and the total surface area including the base. A cone holds exactly a third of a cylinder with the same base and height.

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Base radius

Height

volume (cubic units)

Slant height0

Surface area0

The formulas

Volume = one third times pi times radius squared times height
Slant height = square root of radius squared plus height squared
Surface area = pi times radius times slant height, plus pi times radius squared

Worked example

A cone with a 3 unit radius and 8 unit height has a volume of about 75.4 cubic units, a slant height of about 8.54, and a surface area of about 108.8 square units.

Related calculators

Cylinder Volume Calculator: volume of a cylinder.
Sphere Volume Calculator: volume of a sphere.
Circle Calculator: area and circumference.
Pythagorean Theorem Calculator: find a side.

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