Cone Volume Calculator

This calculator works out the volume, slant height and total surface area of a cone from two measurements: the base radius and the height. A cone's volume is useful for real jobs, such as estimating how much sand, gravel, concrete or grain a conical pile or funnel-shaped container holds, sizing a paper or plastic cone, or checking a maths assignment. You enter the base radius and the height in any consistent unit, and the calculator instantly returns the volume in cubic units, the slant height, and the total surface area, covering both the curved side and the circular base. Behind the scenes it applies the standard formulas: volume equals one third times pi times the radius squared times the height, slant height comes from Pythagoras as the square root of the radius squared plus the height squared, and surface area is pi times the radius times the slant height plus pi times the radius squared for the base. A cone always holds exactly a third of the volume of a cylinder with the same base and height, a handy way to sanity-check your answer. Because results depend entirely on the two measurements you supply, keep your units consistent, and remember real-world cones such as piles of material are rarely perfectly shaped, so treat the figures as a close geometric estimate rather than an exact measurement.

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