Cubic Yards of Dirt Calculator
Calculate exactly how many cubic yards of dirt, topsoil, or fill you need for any project. Handles rectangular, circular, and triangular areas.
How to calculate cubic yards of dirt
Cubic yards is the standard unit for ordering bulk dirt, soil, gravel, or mulch from a landscape supplier. Most delivery trucks measure their loads in cubic yards, so calculating this correctly avoids over-ordering (wasting money) or under-ordering (requiring a second delivery).
The key is converting all your measurements to feet before multiplying. Depth is usually the trickiest measurement — if your depth is in inches, divide by 12 to convert to feet first. Once you have length, width, and depth all in feet, multiply them together to get cubic feet, then divide by 27 to get cubic yards.
For circular areas like tree rings or round planting beds, the formula uses the circle's radius: Volume = π × radius² × depth. For triangular areas such as corner fills or wedge-shaped gardens, use: Volume = 0.5 × base × height × depth.
Formulas used
Worked example — rectangular garden bed
| Input | Value |
|---|---|
| Length | 15 feet |
| Width | 10 feet |
| Depth | 6 inches = 0.5 ft |
- Volume = 15 × 10 × 0.5 = 75 cubic feet
- 75 ÷ 27 = 2.78 cubic yards
- Add 10% for compaction: 2.78 × 1.10 = 3.06 cubic yards to order
Dirt ordering tips
Always round up when ordering. Landscape suppliers typically sell in half or full cubic yard increments. Round up to the nearest available quantity to make sure you have enough material.
Check delivery access. Large dump trucks need clear access with no low-hanging wires or tight turns. If access is difficult, ask about conveyor delivery or smaller truck options, which may cost more.
Test soil quality. For garden projects, ask for the soil content, pH, and organic matter percentage before ordering large quantities. Poor quality fill dirt can harm plant growth if used in planting beds.
Frequently asked questions
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Measure the length, width, and depth of the area. Convert all measurements to feet (divide inches by 12, divide yards by 3). Multiply L × W × D to get cubic feet, then divide by 27 to convert to cubic yards. For example, a 12×8 ft area at 4 inches deep: 12 × 8 × (4÷12) = 32 cubic feet ÷ 27 = 1.19 cubic yards.
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There are exactly 27 cubic feet in one cubic yard. This is because one yard = 3 feet, so one cubic yard = 3 ft × 3 ft × 3 ft = 27 cubic feet. When calculating from feet measurements, always divide your cubic foot result by 27 to get cubic yards.
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Dry topsoil weighs approximately 1,700–2,000 lbs per cubic yard (850–1,000 kg). Wet soil or clay can weigh 2,200–2,800 lbs per cubic yard. Sandy dry soil is lighter at about 1,600 lbs per cubic yard. Moist fill dirt averages around 2,100 lbs (1 US ton) per cubic yard.
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A standard short-bed pickup truck carries about 1 cubic yard of dirt. A long-bed pickup can hold 1.5–2 cubic yards. A small dump trailer holds 2–4 cubic yards, while larger contractor trailers hold 6–10 cubic yards. Soil is heavy — a cubic yard of wet clay may exceed safe payload limits for some trucks.
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Yes, if the dirt will be compacted after placement, you need to order more than the calculated volume. Loose fill compacts to about 80–90% of its volume when tamped. Add roughly 10–15% extra if the fill will be compacted for a driveway, foundation, or similar application.
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Topsoil is the upper 6–12 inches of soil, rich in organic matter and nutrients. It is used for gardens, lawns, and planting beds. Fill dirt is subsoil material used to raise grade levels, fill excavations, or build up a base — it has little to no organic matter. Subsoil is the layer below topsoil, usually lower quality but more stable for structural fill.
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Measure the bed length, width, and desired soil depth. Multiply all three and divide by 27 for cubic yards. A typical 4 × 8 ft raised bed filled to 12 inches deep needs: 4 × 8 × 1 = 32 cubic feet ÷ 27 = 1.19 cubic yards of soil mix.
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A standard 1 cubic foot bag of soil weighs about 40–50 lbs. You need 27 one-cubic-foot bags to equal one cubic yard. If buying 2 cubic foot bags (common at garden centers), you need about 14 bags per cubic yard. For larger projects, bulk delivery is almost always cheaper than bagged soil.
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Break the area into simpler shapes (rectangles, triangles, circles) and calculate each separately, then add the volumes. For curved or truly irregular shapes, measure at multiple points and average the dimensions. Some landscaping apps and tools also let you trace irregular shapes digitally for a more accurate estimate.