Cubic Yard Calculator
Calculate exact cubic yards for concrete, gravel, fill dirt, and more. Supports all shapes — rectangle, circle, L-shape, triangle, and custom areas.
Area Shape *
Rectangle — Length × Width
Frequently Asked Questions
How to Calculate Cubic Yards — Complete Formula Guide
A cubic yard is a unit of volume equal to 27 cubic feet (3 ft × 3 ft × 3 ft). It is the standard unit used by concrete suppliers, gravel delivery companies, and landscaping material yards in the United States. Knowing how to calculate cubic yards correctly prevents costly over-orders and job site shortages.
The cubic yard formula is: Cubic Yards = (Length ft × Width ft × Depth ft) ÷ 27. If your depth measurement is in inches, convert it first by dividing by 12. For example, a 20 ft × 15 ft patio slab at 4 inches (0.33 ft) thick needs 20 × 15 × 0.33 ÷ 27 = 3.67 cubic yards of concrete. Always round up and add a 10% waste buffer when ordering.
Standard Thickness for Common Projects
| Project | Standard Thickness | Material |
|---|---|---|
| Residential concrete driveway | 4 inches | Concrete |
| Commercial / heavy vehicle slab | 6 inches | Concrete |
| Sidewalk / footpath | 3–4 inches | Concrete |
| Concrete patio | 3.5–4 inches | Concrete |
| Driveway gravel base | 4–6 inches | Gravel / crushed stone |
| Raised garden bed fill | 12–18 inches | Topsoil |
| Backfill / foundation | As needed | Fill dirt |
| Mulch garden beds | 2–3 inches | Mulch |
Square Feet to Cubic Yards Conversion
If you already know your square footage and just need to add depth, use this shortcut: Cubic Yards = (Square Feet × Depth in inches) ÷ 324. This is derived from the full formula and saves the step of converting inches to feet. Our calculator accepts area directly via the "Enter Area" shape option if you know your square footage.
Important Tips Before You Order
- ▸Always add 10% for concrete — waste from forms, spillage, and slight over-pour is normal and expected.
- ▸Minimum concrete order — ready-mix trucks typically have a 1 cubic yard minimum. For small jobs under 0.5 yd³, use bagged concrete mix instead.
- ▸Measure twice — an error of just 2 inches in depth on a 500 sq ft area means 3+ extra cubic yards. Double-check all measurements before ordering.
- ▸Weight matters for delivery — concrete weighs ~2 tons per cubic yard. Confirm your access road and truck weight limit before scheduling delivery.
Use our free cubic yard calculator above for concrete slabs, gravel driveways, topsoil fills, and any other volume calculation. Supports rectangles, circles, triangles, L-shapes, and custom areas — with instant weight and cost estimates.