Cone Calculator

This calculator finds a cone's volume, slant height, and surface area for anyone working with funnels, roofs, or conical containers.

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Enter the base radius and perpendicular height. If slant height is requested, measure along the cone's side from the rim to the tip.

Slant height is s = square root of (radius^2 + height^2). Volume is V = (1/3) × pi × radius^2 × height, and total surface area is A = pi × radius^2 + pi × radius × slant height.

Worked example

A cone with a radius of 3 cm and height of 4 cm has a slant height of 5 cm. Its volume is (1/3) × pi × 3^2 × 4 = 37.70 cm³, and its total surface area is pi × 3^2 + pi × 3 × 5 = 75.40 cm².

Common questions

Is slant height the same as vertical height?

No. Vertical height runs straight from the tip to the center of the base, while slant height follows the cone's side.

How do I find the area without the base?

Use the lateral area formula, A = pi × radius × slant height. This counts only the curved side.

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