Volume estimation guide
How to Calculate Cubic Yards
Multiply length × width × depth in feet, then divide by 27. This works for concrete, gravel, mulch, dirt, sand, and other materials sold by volume.
Formula: length in feet × width in feet × depth in feet ÷ 27 = cubic yards.
Three Steps
- Measure the length and width of the project area in feet.
- Measure the material depth. Convert inches to feet by dividing by 12.
- Multiply the three measurements and divide by 27.
Worked Examples
| Project | Calculation | Result |
|---|---|---|
| 10 × 10 patio at 4 inches | 10 × 10 × 0.333 ÷ 27 | 1.23 cubic yards |
| 20 × 20 driveway at 4 inches | 20 × 20 × 0.333 ÷ 27 | 4.94 cubic yards |
| 200 sq ft mulch bed at 3 inches | 200 × 0.25 ÷ 27 | 1.85 cubic yards |
| 4 × 8 raised bed at 12 inches | 4 × 8 × 1 ÷ 27 | 1.19 cubic yards |
Allow for Overage
Multiply the calculated volume by 1.10 for a 10 percent overage. This helps account for compaction, spillage, uneven ground, and small measurement differences.
FAQ
Multiply length, width, and depth in feet, then divide the result by 27.
Divide the number of inches by 12. For example, 4 inches equals 0.333 feet.
A 10 percent overage is a common planning allowance for waste, compaction, uneven ground, and measuring differences.
No. The volume formula is the same, but material density changes the estimated weight.