This Frustum of a Cone Lateral Surface Area Calculator helps you find the curved surface area of a truncated cone using radii and slant height.
The lateral surface area represents only the curved outer surface, excluding the top and bottom circles.
| Bottom Radius (R) | Top Radius (r) | Slant Height (l) | Lateral Area |
|---|---|---|---|
| 5 | 3 | 10 | 251.327412 |
| 8 | 4 | 12 | 452.389342 |
| 6 | 2 | 7 | 175.929189 |
| 10 | 5 | 15 | 706.858347 |
| 7 | 3 | 8 | 251.327412 |
Steps to calculate:
1. Add the two radii (R + r).
2. Multiply the result by the slant height (l).
3. Multiply everything by π.
This tool is useful when you only need the curved surface area, for example in material estimation or coating calculations.
It avoids unnecessary steps and focuses only on the truncated cone lateral surface area.
• Lateral area excludes circular bases.
• Used in manufacturing pipes, lampshades, and funnels.
• Slant height is always longer than vertical height.
• The formula is derived from cone geometry.
• Practical in real-world surface covering tasks.