Cone Calculator

Volume equals (1/3) x pi x r^2 x h, where r is the base radius and h is the perpendicular height. A cone holds exactly one-third the volume of a cylinder with the same base and height, so a cone with radius 3 in and height 6 in has a volume of about 56.55 cubic inches.

Slant height is the straight-line distance from the apex down to the base edge. The calculator derives it with the Pythagorean theorem: l = sqrt(r^2 + h^2). For example, a cone with radius 4 ft and height 3 ft has a slant height of 5 ft.

Lateral surface area is the curved side only: pi x r x l, where l is the slant height. Total surface area adds the circular base (pi x r^2), giving pi x r^2 + pi x r x l. Use lateral area for an open cone like a funnel or party hat; use total area when the base is solid and counts as part of the surface.

Enter the base radius and perpendicular height as positive numbers in the same unit. The calculator returns volume, slant height, base area, lateral surface area, total surface area, diameter, and base circumference, all rounded to 6 decimal places.

Yes. The formulas are unit-agnostic, so you can enter inches, feet, centimeters, or meters. Area results are in the squared unit and volume in the cubed unit. Just make sure radius and height use the same unit before you enter them, and convert one if they differ.