Cone Calculator
Volume, lateral and total surface area of a cone.
How it works
Volume = πr²h ÷ 3; slant l = √(r²+h²); Lateral = πrl
A cone’s volume is one third of a cylinder with the same base and height. Surface = lateral + base circle.
Worked example
Radius 3, height 4:
Slant l = √(3²+4²) = 5; volume π×3²×4 ÷ 3 ≈ 37.70; lateral area π×3×5 ≈ 47.12; total ≈ 75.40.
Notes and limitations
Volume is one third of the matching cylinder. Lateral area uses the slant height, not the vertical height — the most common mistake. Slant, radius and height form a right triangle.