How the cone calculator works
Piles of gravel, sand, soil, and mulch settle into a cone, which is why this calculator is popular with landscapers and contractors.
Use this cubic yard calculator for a cone to get cubic yards, cubic feet, cubic meters, and a cost estimate in one step.
The calculator multiplies out the volume in cubic feet, then divides by 27, because a cubic yard is a cube that is 3 feet on each side. For this shape the formula is shown below in words and symbols.
In plain words: one third of pi times radius squared times height, then divide by 27 if your answer is in cubic feet. Mixed units are fine. Pick feet, inches, yards, meters, or centimeters next to each box and the tool converts them for you.
Worked example for a cone
Take a cone with base diameter 10 ft, height 4 ft. The volume works out to 104.72 cubic feet. Divide by 27 and you get 3.88 cubic yards. With 10 percent extra for waste, order about 4.27 cubic yards.
Measuring a cone
Measure the width of the pile at the ground for the diameter, and its height at the peak.
Common uses for the cone calculator
- Stockpiles of gravel, sand, and soil
- Mulch piles from a delivery
- Salt and aggregate piles
- Cone shaped mounds
Cone volume at different sizes
The table scales the example above so you can see how fast volume grows. Doubling the depth doubles the volume. Doubling every length quadruples the area, and with the same depth the volume quadruples too.
| Size | Cubic feet | Cubic yards | With 10 percent extra |
|---|---|---|---|
| 5 ft by 4 ft | 26.18 | 0.97 | 1.07 |
| 10 ft by 4 ft | 104.72 | 3.88 | 4.27 |
| 15 ft by 4 ft | 235.62 | 8.73 | 9.60 |
| 20 ft by 4 ft | 418.88 | 15.51 | 17.07 |
| 30 ft by 4 ft | 942.48 | 34.91 | 38.40 |
| 10 ft by 8 ft | 209.44 | 7.76 | 8.53 |
| 20 ft by 8 ft | 837.76 | 31.03 | 34.13 |
What the 3.88 cubic yard example weighs
Volume is only half of the story when a truck is hauling the load. The table shows planning weights for the example volume in several materials.
| Material | US tons | Pounds |
|---|---|---|
| Topsoil | 4.27 | 8,533 |
| Mulch | 1.36 | 2,715 |
| Gravel | 5.43 | 10,860 |
| Sand | 5.24 | 10,472 |
| Concrete | 7.85 | 15,708 |
| Compost | 1.94 | 3,879 |
These figures are planning estimates. Real material varies in moisture, size, and compaction, so confirm weights and order quantities with your supplier.
Frequently asked questions
How do I calculate cubic yards for a cone?
Find the volume in cubic feet, then divide by 27. For this shape: one third of pi times radius squared times height. Convert inches to feet first by dividing by 12.
How many cubic yards is the example cone?
Base diameter 10 ft, height 4 ft comes to 3.88 cubic yards, or 104.72 cubic feet.
How much extra should I order?
Most people add 5 to 10 percent for waste, and 10 to 15 percent for rough ground or loose material.
Can I use metric units?
Yes. Choose meters or centimeters next to any length. The result still shows cubic yards, and the cubic meter figure sits beside it.
Why does the answer change with the material?
The volume does not change, but weight and bag counts do, because each material has a different density.