Cone Volume Calculator
A cone holds exactly one third of the cylinder with the same base and height. Use it for piles of gravel, sand or grain, funnels and ice-cream cones.
V = ⅓ πr²h
- Surface area
- 108.8 ft²
- V = ⅓ × π × 3² × 8 = 75.3982 ft³
- Slant height = √(3² + 8²) = 8.544 ft
Volume in other units
| m³ | 2.135 |
| liters | 2,135.04 |
| ft³ | 75.3982 |
| yd³ | 2.7925 |
| in³ | 130,288 |
| US gallons | 564.018 |
| cm³ (mL) | 2,135,040 |
How to find the volume of a cone
Volume: V = ⅓ πr²h. Surface area: SA = πr(r + √(r² + h²)).
- Measure in one unit. The answer comes out in that unit cubed (ft³, m³).
- Substitute into the formula; the calculator shows the steps with your numbers.
- Read liters, gallons, cubic yards and more in the conversion table. 1 ft³ ≈ 7.48 US gallons ≈ 28.32 liters.
Three cones fill one cylinder
Take a cone and a cylinder with the same round base and the same height. Pour the cone full of water into the cylinder three times and it's full — which is why the cone formula is ⅓ πr²h. The same ⅓ links a pyramid to the box around it.
Cylinder is ⅓ full
Questions people ask
How do I estimate a gravel pile?
Measure around the base (circumference) and the height. r = circumference ÷ 2π, then V = ⅓πr²h. Divide cubic feet by 27 for cubic yards.
Stuck on a word problem?
Paste a homework question or describe your project. The AI tutor names the formula and works it through step by step. Always check the result with the calculator above.