A cubic yard is 27 cubic feet — a 3 ft × 3 ft × 3 ft cube. Concrete, mulch, gravel, and topsoil are sold by the cubic yard, so knowing the volume of the area you need to fill determines how much to order. Enter length, width, and depth in your preferred unit and the calculator converts to cubic yards. Add a price per yard to get a cost estimate.
The Cubic Yard Formula
Convert all measurements to feet, then multiply length × width × depth to get cubic feet. Divide by 27 to convert to cubic yards. For example, a driveway pad 20 ft long, 10 ft wide, and 4 inches (0.333 ft) deep is 20 × 10 × 0.333 = 66.6 cubic feet, or about 2.47 cubic yards of concrete.
Common Material Coverage
One cubic yard of mulch covers roughly 160 square feet at 2 inches deep. One cubic yard of gravel covers about 100 square feet at 3 inches deep. Concrete is typically poured 4 inches thick for patios and 6 inches for driveways. Topsoil is usually spread 2–4 inches deep for lawn preparation. These rules of thumb help cross-check the calculator output.
How Much Extra to Order
Order 5–10% more than the calculated amount. Uneven ground, compaction, and spillage consume material. For concrete, the standard is to add 10% because you cannot easily reorder mid-pour. For loose materials like mulch or gravel, 5% extra is usually sufficient since small shortfalls can be topped up later.
Cubic Yards vs. Tons
Loose materials are sometimes sold by weight. The conversion depends on the material: gravel weighs about 1.4 tons per cubic yard, sand about 1.3 tons, and topsoil about 1.1 tons. Mulch is much lighter at roughly 0.4 tons per cubic yard. If your supplier quotes by the ton, convert using the material's density to avoid over- or under-ordering.
FAQ
Q: How many cubic yards of concrete do I need for a 10×10 patio?
A: At the standard 4-inch depth: 10 × 10 × 0.333 = 33.3 cubic feet ÷ 27 = 1.23 cubic yards. Order at least 1.35 yards to account for waste.
Q: How do I convert cubic yards to cubic meters?
A: Multiply cubic yards by 0.7646. One cubic yard equals about 0.765 cubic meters.
Q: Why does the depth need to be in the same unit as length and width?
A: The calculator handles unit conversion automatically. Select your preferred unit and enter all three dimensions in that unit — it converts to feet internally before computing cubic yards.