How Many Square Feet in a Cubic Yard? (By Depth)
Short answer: it depends on how deep you spread it. One cubic yard covers 324 square feet at 1 inch deep, 108 sq ft at 3 inches, and 81 sq ft at 4 inches. The rule: square feet covered = 324 ÷ depth in inches.
Square feet measure area and cubic yards measure volume, so there’s no single conversion: the depth links them. To work out yards for your own area and depth, use the cubic yard calculator.
Square feet per cubic yard, by depth
| Depth | One cubic yard covers |
|---|---|
| 1 in | 324 sq ft |
| 2 in | 162 sq ft |
| 3 in | 108 sq ft |
| 4 in | 81 sq ft |
| 6 in | 54 sq ft |
| 8 in | 40.5 sq ft |
| 12 in | 27 sq ft |
Where 324 comes from
A cubic yard is 3 ft × 3 ft × 3 ft = 27 cubic feet. Spread 1 inch deep (1/12 of a foot), 27 cubic feet covers 27 × 12 = 324 square feet. Twice as deep covers half the area, and so on.
Square feet to cubic yards
Going the other way: cubic yards = square feet × depth in inches ÷ 324.
| Area | Depth | Cubic feet | Cubic yards |
|---|---|---|---|
| 100 sq ft | 3 in | 25 | 0.93 |
| 200 sq ft | 4 in | 66.7 | 2.47 |
| 500 sq ft | 2 in | 83.3 | 3.09 |
| 1,000 sq ft | 6 in | 500 | 18.52 |
Most suppliers sell in whole or half yards, so round up, and add a little extra for settling with soil and mulch.
Typical depths by material
- Mulch: 2 to 4 inches (university extension guidance), so a yard covers about 81 to 162 sq ft. See the mulch calculator.
- Topsoil: depends on the job. A 4 inch layer means a yard covers 81 sq ft. See the topsoil calculator.
- Gravel: sold by the ton as well as the yard. Use the gravel calculator for both.
- Concrete: a 4 inch slab means a yard covers 81 sq ft. See the concrete calculator for yards and bags.
Common questions
How many square feet does a yard of mulch cover?
About 108 sq ft at 3 inches deep, or 162 sq ft at 2 inches.
How many square feet does a yard of concrete cover?
81 sq ft at 4 inches thick, or 54 sq ft at 6 inches.
How many cubic yards do I need for 1,000 square feet?
At 3 inches deep, 1,000 × 3 ÷ 324 = 9.26 cubic yards. At 4 inches, 12.35 cubic yards.
Sources
- NIST Handbook 44: unit definitions (1 cubic yard = 27 cubic feet).
- University of Illinois Extension: proper mulching techniques: mulch depth of 2 to 4 inches.