Cubic Yard Volume Calculator: Formula & Examples

A cubic yard volume calculator works out the volume of a rectangular space (length × width × height) in cubic yards, which is the standard unit for ordering bulk materials like soil, mulch, and concrete. You enter the dimensions in feet, inches, or yards, and the calculator returns the volume in cubic yards (yd³) — the exact number you need to estimate how much material to order or how much space an object occupies.

Formula

The formula for cubic yards from feet is:

Volume (yd³) = (Length × Width × Depth) / 27

Where:

• Length — the longest horizontal dimension, in feet (ft)
• Width — the shorter horizontal dimension, in feet (ft)
• Depth — the vertical dimension (how deep or tall), in feet (ft)
• 27 — the number of cubic feet in one cubic yard (3 ft × 3 ft × 3 ft)

If you measure in inches, convert to feet first by dividing by 12 (e.g., 6 inches = 0.5 ft). If you measure in yards already, skip the division by 27 — just multiply length × width × depth.

Worked Example

Using the calculator defaults: length = 10 ft, width = 5 ft, depth = 0.5 ft (6 inches).

1. Multiply length × width × depth: 10 × 5 × 0.5 = 25 cubic feet
2. Divide by 27: 25 ÷ 27 = 0.926 cubic yards
3. Rounded to two decimals: 0.93 yd³

So a 10′ × 5′ area covered 6 inches deep needs about 0.93 cubic yards of material. The calculator also shows the volume in cubic feet (25 ft³) for reference.

When to Use a Cubic Yard Calculator

This calculator is most useful for home improvement and landscaping projects where materials are sold by the cubic yard:

• Topsoil or garden soil — for raised beds or filling a lawn area
• Mulch — to cover flower beds at a target depth (usually 2–4 inches)
• Concrete — for footings, slabs, or posts (ready-mix is ordered in cubic yards)
• Sand or gravel — for patios, driveways, or drainage trenches
• Compost or fill dirt — to level a yard or amend soil

It also works for estimating the volume of a large box, a dumpster load, or a storage container — anywhere you need to know how much space a rectangular object takes up in cubic yards.

How to Read the Result

The result is a pure volume — it tells you how much material fits, not how much it weighs. Weight depends on the material’s density, which varies widely:

• Dry topsoil: about 1.0–1.3 tons per cubic yard
• Wet or compacted soil: up to 1.5–1.8 tons per cubic yard
• Mulch (wood bark): about 0.4–0.6 tons per cubic yard
• Sand: about 1.2–1.4 tons per cubic yard
• Gravel: about 1.3–1.5 tons per cubic yard

When ordering from a supplier, they usually quote both volume and weight, so ask for the weight per cubic yard of the specific material. Also note that most suppliers deliver in whole or half-yard increments — you may need to round up (e.g., 0.93 yd³ becomes 1 yd³) to avoid a shortage.

Common Mistakes and How to Avoid Them

The most frequent error is mixing units. If you measure length and width in feet but depth in inches, you must convert the depth to feet first. For example, 4 inches = 4 ÷ 12 = 0.333 ft. Failing to convert will give a result 12 times too large.

Another mistake is using the formula for a cylinder or irregular shape. This calculator only works for rectangular prisms (boxes). For a round flower bed, you need the cylinder volume formula (π × radius² × depth) and then convert to cubic yards (divide by 27). For a triangular trench, use 0.5 × base × height × length.

Rounding too early also causes errors. Keep at least two decimal places through the calculation, then round the final answer to two decimals (or to the nearest half-yard for ordering).

Finally, remember that volume is not the same as capacity in practice — when filling a container, material may settle or compact, so order 5–10% extra for loose materials like mulch or soil.

Limits of the Formula

The formula assumes a perfectly rectangular space with flat, parallel sides. Real-world areas often have slopes, curves, or irregular boundaries. For such shapes, break the area into smaller rectangles, calculate each, and add the volumes together.

The formula also ignores compaction, moisture content, and waste. If you’re ordering fill dirt for a foundation, the actual amount needed may differ from the calculated volume because the dirt compresses. Always confirm with your supplier and consider a small overage.

For very large or very small dimensions, double-check your unit conversions. A depth of 0.5 ft is 6 inches, but a depth of 0.5 inches is only about 0.042 ft — a huge difference in volume.

Frequently Asked Questions

How many cubic feet are in a cubic yard?

Exactly 27 cubic feet. One yard is 3 feet, so a cube that is 1 yard on each side is 3 × 3 × 3 = 27 cubic feet. This is why you divide by 27 when converting from cubic feet to cubic yards.

How do I calculate cubic yards from inches?

Convert all three dimensions to feet first by dividing each inch measurement by 12. Then multiply length × width × depth (all in feet) to get cubic feet, and divide by 27 to get cubic yards. For example, 120 in × 60 in × 6 in = (120/12) × (60/12) × (6/12) = 10 × 5 × 0.5 = 25 ft³ ÷ 27 = 0.93 yd³.

What is the difference between cubic yards and square yards?

Cubic yards measure volume (three-dimensional space), while square yards measure area (two-dimensional surface). A square yard is 1 yard × 1 yard, but a cubic yard adds a depth dimension. To convert square yards to cubic yards, you multiply by the depth in yards. For example, 10 square yards at 0.5 yard deep = 5 cubic yards.

How much does a cubic yard of concrete weigh?

Concrete weighs about 4,000–4,200 pounds per cubic yard (roughly 2 tons). However, this calculator only gives volume, not weight. For other materials, weight per cubic yard varies: topsoil ~2,000–2,600 lbs, sand ~2,700–3,000 lbs, gravel ~2,800–3,400 lbs, and mulch ~600–1,000 lbs. Check with your supplier for the exact density.

Can I use this calculator for a circular area?

No, this calculator is for rectangular boxes only. For a circular area (like a round garden bed), use the formula: Volume = π × radius² × depth (in feet) ÷ 27. For example, a circle with a 5-foot radius and 0.5-foot depth: 3.14159 × 25 × 0.5 = 39.27 ft³ ÷ 27 = 1.45 yd³.

Should I round up when ordering materials?

Yes, it’s usually wise to round up to the next whole or half cubic yard, and add 5–10% extra for waste, settling, or spillage. If you calculate 0.93 yd³, order 1 yd³. For a larger project, 10.2 yd³ might become 11 yd³ to ensure you don’t run short, since delivery fees often make a second trip costly.

Related

• Bark Calculator: Cubic Feet & Coverage
• Bank Cubic Feet Calculator: Volume & Swell
• Backfill Cubic Yard Calculator: How Much Soil?

in l | Length | ft | 10 | 0
in w | Width | ft | 5 | 0
in h | Depth | ft | 0.5 | 0
out yards | Cubic yards | yd³ | (l * w * h) / 27 | 2
out feet | Cubic feet | ft³ | l * w * h | 2