How to convert square feet to cubic yards
Multiply square feet by the depth in inches and divide by 324.
A cubic yard is 27 cubic feet. Spread 1 inch (1/12 ft) deep, 27 cubic feet covers 27 × 12 = 324 square feet. Every extra inch of depth divides that by one more: 162 sq ft at 2 in, 108 at 3 in, 81 at 4 in. Clemson Extension uses the same 324 rule in its mulch guide,[2] and Colorado State rounds it to three cubic yards per 1,000 square feet at 1 inch.[3]
square feet covered by 1 yd³ = 324 ÷ depth in inches
Metric works the same way. A cubic meter spread 1 cm deep covers 100 m², so at 5 cm it covers 20 m² (the figure the RHS gives for a bulk bag of gravel)[4] and at 10 cm it covers 10 m². The conversion factors behind both rules are exact.[1]
Coverage of one cubic yard
One cubic yard covers 324 sq ft at 1 inch, 108 sq ft at 3 inches and 54 sq ft at 6 inches.
| Depth | Square feet | Square yards | Square meters |
|---|---|---|---|
| 0.5 in (1.3 cm) | 648 | 72 | 60.2 |
| 1 in (2.5 cm) | 324 | 36 | 30.1 |
| 2 in (5.1 cm) | 162 | 18 | 15.1 |
| 3 in (7.6 cm) | 108 | 12 | 10 |
| 4 in (10.2 cm) | 81 | 9 | 7.5 |
| 5 in (12.7 cm) | 65 | 7.2 | 6 |
| 6 in (15.2 cm) | 54 | 6 | 5 |
| 8 in (20.3 cm) | 41 | 4.5 | 3.8 |
| 12 in (30.5 cm) | 27 | 3 | 2.5 |
Coverage of one cubic meter
One cubic meter covers 20 m² at 5 cm and 10 m² at 10 cm.
| Depth | Square meters | Square feet |
|---|---|---|
| 2.5 cm (1 in) | 40 | 431 |
| 5 cm (2 in) | 20 | 215 |
| 7.5 cm (3 in) | 13.3 | 144 |
| 10 cm (3.9 in) | 10 | 108 |
| 15 cm (5.9 in) | 6.7 | 72 |
| 20 cm (7.9 in) | 5 | 54 |
| 30 cm (11.8 in) | 3.3 | 36 |
Coverage of one bag
Bag labels give the volume. A 2 cu ft bag spread 2 inches deep covers 2 × 12 ÷ 2 = 12 sq ft, which is what one mulch brand prints on its 2 cu ft bag.[5] The general rule is bag cubic feet × 12 ÷ depth in inches.
| Bag size | 1 in | 2 in | 3 in | 4 in |
|---|---|---|---|---|
| 0.5 cu ft (14 L) | 6 | 3 | 2 | 1.5 |
| 1 cu ft (28 L) | 12 | 6 | 4 | 3 |
| 1.5 cu ft (42 L) | 18 | 9 | 6 | 4.5 |
| 2 cu ft (57 L) | 24 | 12 | 8 | 6 |
| 3 cu ft (85 L) | 36 | 18 | 12 | 9 |
For a metric bag: liters ÷ 10 ÷ depth in cm = square meters. A 50 L bag at 5 cm covers 50 ÷ 10 ÷ 5 = 1 m². The bags per cubic yard page turns a bulk volume into a bag count, and cubic feet to cubic yards converts between the units. To measure the area itself, use the square yard calculator.
Depth is the real decisionThe coverage math is exact; the depth you choose is what changes the order. See the depth guides for mulch, gravel and topsoil.
Frequently asked questions
How many square feet does a yard of mulch cover?
At 3 inches deep, 108 sq ft. At 2 inches, 162 sq ft. At 4 inches, 81 sq ft. The material does not change the coverage, only the depth does.
How much does a yard of gravel cover at 2 inches?
162 square feet (18 square yards), or about 15 m².
How many square feet does a cubic yard of soil cover 6 inches deep?
324 ÷ 6 = 54 square feet.
How much does a cubic meter cover?
100 ÷ depth in cm. At 5 cm it covers 20 m², at 7.5 cm about 13.3 m², at 10 cm 10 m².