Calculate cubic yards for concrete, gravel, mulch, dirt & soil. Convert area & depth to cubic yards, cubic feet, and tons instantly.
How to Use This Cubic Yard Calculator
Pick a measurement mode. Use Area × Depth for anything spread over a surface — concrete slabs, gravel driveways, mulch beds, topsoil — and enter length and width in feet plus the depth in inches. Use Length × Width × Height for boxes, trenches, and holes where all three dimensions are in feet. Choose your material to get an automatic tons estimate, and add a waste/overage percentage when you need a safety margin (always do this for concrete). The calculator instantly shows cubic yards, cubic feet, and tons.
How to Calculate Cubic Yards: The Complete Guide
The cubic yard is the standard unit for ordering bulk materials in the United States — concrete, gravel, mulch, sand, and topsoil all come by the yard. Yet it trips people up because it mixes units: you measure your project in feet and inches, but order in cubic yards, and sometimes pay by the ton. Get the conversion wrong and you either run short mid-project or pay to haul away a pile you didn't need. Here's how to get it right every time.
The Core Formula: Divide Cubic Feet by 27
A cubic yard is a cube three feet on every side: 3 ft × 3 ft × 3 ft = 27 cubic feet. So the universal method is to calculate your volume in cubic feet, then divide by 27:
- Cubic feet = length (ft) × width (ft) × depth (ft)
- Cubic yards = cubic feet ÷ 27
Example: a patio slab 12 ft long, 10 ft wide, and 4 inches thick. Convert 4 inches to feet (4 ÷ 12 = 0.333 ft). Volume = 12 × 10 × 0.333 = 40 cubic feet. Cubic yards = 40 ÷ 27 = 1.48 cubic yards.
The Shortcut: Square Feet × Inches ÷ 324
Because most projects are measured as an area with a depth in inches, there's a handy shortcut that skips the foot conversion. Since 27 cubic feet × 12 inches per foot = 324, you can go straight from square feet and inches:
Cubic yards = (square feet × depth in inches) ÷ 324
Same patio: 120 sq ft × 4 inches = 480, divided by 324 = 1.48 cubic yards. Identical answer, one fewer step. This is the formula our calculator uses in Area × Depth mode.
Material Density Chart (Cubic Yards to Tons)
Bulk suppliers often sell and deliver by the ton, so you need to convert your volume to weight. Multiply cubic yards by the material's density. These are typical dry values — wet material weighs more:
| Material | Tons per Cubic Yard | Notes |
|---|
| Gravel / Crushed Stone | 1.4 | #57 stone, crusher run |
| Sand | 1.35 | Concrete or masonry sand |
| Topsoil | 1.1 | Screened, slightly moist |
| Dirt / Fill | 1.25 | Compacted fill dirt |
| Mulch | 0.5 | Dry; wet mulch up to 0.8 |
| Concrete (cured) | 2.0 | ≈ 4,000 lb per yard |
Cubic Yard Coverage Table (How Much Area One Yard Covers)
The most common real-world question is "how much ground will one cubic yard cover?" The answer depends entirely on depth. One cubic yard is 324 square-feet-inches, so coverage = 324 ÷ depth in inches:
| Depth | Area 1 Cubic Yard Covers | Typical Use |
|---|
| 1 inch | 324 sq ft | Top dressing |
| 2 inches | 162 sq ft | Mulch refresh |
| 3 inches | 108 sq ft | Mulch beds, decorative gravel |
| 4 inches | 81 sq ft | Concrete slab, gravel base |
| 6 inches | 54 sq ft | Deep gravel, raised beds |
| 12 inches | 27 sq ft | Deep fill, planters |
Ordering Concrete: Always Round Up
Concrete is the one material where coming up short is a genuine emergency. Once the ready-mix truck pours and leaves, you cannot seamlessly add more — a cold joint forms between the old and new concrete, creating a weak line. That's why the industry standard is to order 5-10% more than your calculated volume. For a job that calculates to 3.0 cubic yards, order 3.25-3.3 yards. Ready-mix is sold in quarter-yard increments, and the small cost of slight overage is nothing compared to the cost of a failed pour. Most suppliers also charge a "short load" fee for orders under about 1 cubic yard.
Bags vs. Bulk: When to Switch
Bagged material is convenient for small jobs but expensive per yard. A 2-cubic-foot bag of mulch means you need 13.5 bags per cubic yard; at $4 a bag that's $54/yard, while bulk mulch delivered runs $30-45/yard. The break-even is usually around 8-10 bags — beyond that, bulk delivery wins on price even after the delivery fee. For soil and gravel the math is even more lopsided because those materials are heavy and bags are small. Rule of thumb: if you need more than half a cubic yard, price out bulk delivery.
Common Cubic Yard Mistakes
- Dividing by 3 instead of 27: A yard is 3 feet linearly, but a cubic yard is 3³ = 27 cubic feet. This is the single most common error and it under-orders by two-thirds.
- Forgetting to convert depth to feet: Multiplying square feet by depth in inches gives cubic-feet-inches, not cubic feet. Either convert inches to feet first, or use the ÷324 shortcut.
- Confusing tons with yards: A supplier quote "per ton" is weight; your calculation is volume. Always convert using the density chart before comparing prices.
- Ordering exact volume for concrete: Never order the precise calculated amount. Spillage, uneven subgrade, and form bulge all consume extra — build in 5-10%.