Cone Volume Calculator
Calculate the volume of a cone from its base radius or diameter and its height, along with the slant height and surface area. Enter a top radius as well and it solves a truncated cone (frustum) — the shape of a bucket, cup or lampshade.
- Slant height
- 5 in
- Side (lateral) area
- 47.12 in²
- Total surface area
- 75.4 in²
Saved setups
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Your recent calculations
Results you calculate here are kept on this device so you can come back to them.
Formula
How to use it
- Choose whether your widths are radii or diameters.
- Enter the base width and the vertical height.
- Leave the top width at 0 for a pointed cone, or enter it for a cut-off cone.
- Read the volume, slant height and surface areas.
Worked examples
Radius 3 in and height 4 in: 37.70 in³ (0.618 liters), slant height 5 in
- Volume
- 37.7 in³
- Slant height
- 5 in
- Side (lateral) area
- 47.12 in²
- Total surface area
- 75.4 in²
A cone 2 m across and 3 m tall: 3.142 m³
- Volume
- 3.14 m³
A frustum with radii 6 cm and 3 cm, 4 cm tall: 263.89 cm³
- Volume
- 263.89 mL
- Slant height
- 5 cm
- Side (lateral) area
- 141.37 cm²
- Total surface area
- 282.74 cm²
Height versus slant height
The height in the volume formula is measured straight up the middle, from the center of the base to the tip. The slant height runs along the sloping side and is always longer. If you can only measure the slant, the vertical height is √(slant² − radius²).
Questions people ask
What is the volume of a cone with radius 3 and height 4?
⅓ × π × 9 × 4 = 37.70 cubic units. Its slant height is exactly 5.
How does a cone compare with a cylinder?
A cone holds exactly one third of a cylinder with the same base and height.
How do I find the volume of a bucket?
Treat it as a frustum: enter the larger diameter as the base, the smaller as the top, and the vertical depth as the height. Switch the result to gallons or liters.