Cone Calculator
Compute slant height, base area, lateral area, total surface area, and volume of a right circular cone.
Cone formulas
Slant heightl = √r2 + h2
VolumeV = 13πr2h
Lateral areaL = πrl
Total surface areaSA = πr(r + l)
Where r = base radius, h = vertical height, l = slant height
Worked examples
A cone has radius 3 and height 4. Find the slant height, volume and surface area.
- l = √9 + 16 = 5
- V = 13π × 9 × 4 = 12π
- L = π × 3 × 5 = 15π
- SA = π × 3 × (3 + 5) = 24π
Answer: l = 5, V ≈ 37.70, L ≈ 47.12, SA ≈ 75.40
Tips & common mistakes
- A cone holds exactly one third of a cylinder with the same base and height.