Cubic Yard Calculator

Exactly 27. A cubic yard is a cube three feet on every side, and 3 × 3 × 3 = 27 cubic feet. That is why every bulk-material formula ends in a division by 27: work out length × width × depth in feet to get cubic feet, then divide. A 12 ft × 10 ft bed at 4 inches deep is 40 cubic feet, or 1.48 cubic yards. Bagged material is labeled in cubic feet, so the same number tells you how many bags a yard replaces — 13.5 standard 2 ft³ mulch bags equal one cubic yard, and 27 of the 1 ft³ soil bags.

Spread evenly, a cubic yard covers 324 square feet at 1 inch deep, 162 square feet at 2 inches, 108 at 3 inches, and 81 square feet at the common 4-inch depth. At 6 inches it covers 54 square feet, and at a full 12 inches only 27. The shortcut is 324 ÷ depth in inches. Because mulch beds usually go 2–3 inches, topsoil for seeding 3–4 inches, and a gravel driveway base 4–6 inches, most landscape jobs land near one cubic yard per 100 square feet of bed.

Bulk material moves by truck, so most quarries and soil yards set a 1-yard minimum for pickup and 3–5 yards for delivery, with a flat delivery fee that does not shrink for a small load. Always round up. Material compacts under its own weight, excavations are never perfectly level, and running short means a second trip plus a second delivery charge. Adding 5–10% is normal; for gravel under a slab or driveway plan closer to 10%, because the first inch of stone keys down into the subgrade. Leftover topsoil or gravel is easy to use elsewhere — a half-yard shortfall stops the job.

Quarries usually price crushed stone and sand by the ton, while soil, compost, and mulch sell by the yard. Density converts the two. Crushed stone and screened topsoil both run close to 1.4 tons per cubic yard, the figure used here; dry sand is nearer 1.3, saturated material is heavier, and bark mulch is far lighter at roughly 0.4–0.5 tons per yard. Moisture alone can swing the weight 10–15%, so ask your supplier for the tons-per-yard they actually invoice against before converting a large order. Treat the tonnage shown here as a loading and freight estimate, not a billing figure.

Break the space into rectangles, run each through the calculator, and add the yards together. For a circle, area is 3.1416 × radius², then multiply by depth in feet and divide by 27. The "number of areas" field handles identical shapes at once — four 3 ft × 3 ft planter boxes, or six 12-inch footing holes. For a trench, enter its length, its width, and its depth as usual. Add the sections up, then round the total to the next quarter or half yard, which is the increment most suppliers actually sell in.