How it works
A circular cone frustum has volume πh(R² + Rr + r²)/3. Radii must use the same units as height.
Input definitions
- Bottom radius
- Enter the value in the labeled unit.
- Top radius
- Enter the value in the labeled unit.
- Perpendicular height
- Enter the value in the labeled unit.
A worked example
- Bottom radius
- 3
- Top radius
- 1
- Perpendicular height
- 4
Assumptions & limits
Uses the units and scope stated in the input labels. Results are rounded for display; verify the model is appropriate for your situation.
Sources & review
Maintained by AnsRio. Methods and examples use automated checks; this does not imply independent professional certification.
Method updated 2026-10-18. Content checked against the stated method and examples. Our verification approach.
Common questions
Can the top radius be zero?
Yes. A zero top radius reduces the frustum to a complete cone. Height is perpendicular, not the slanted side length.
How does Circular frustum volume work?
A circular cone frustum has volume πh(R² + Rr + r²)/3. Radii must use the same units as height.
What should I check before using Circular frustum volume?
Uses the units and scope stated in the input labels. Results are rounded for display; verify the model is appropriate for your situation.