What to measure
How to use it
Choose a rectangle or a circle, then enter the dimensions and the depth. Mix units freely: length in feet and depth in inches is the usual combination. For irregular beds, split the area into rectangles and circles and add the results.
The formula
Cubic yards = length (ft) × width (ft) × depth (ft) ÷ 27
For a circle, the area is π × (diameter ÷ 2)².
Worked example: 10 × 10 ft bed, 4 in deep
- 10 × 10 × (4 ÷ 12) = 33.33 cu ft
- 33.33 ÷ 27 = 1.23 cubic yards (0.94 m³)
The same depth over a round bed 10 ft across: π × 5² × (4 ÷ 12) = 26.18 cu ft = 0.97 cubic yards.
Coverage at common depths
| Depth | Area covered by 1 cubic yard |
|---|---|
| 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 |
Most suppliers sell in half- or whole-yard increments, so round up.
Cubic yards by area and depth
| Area | 2 in deep | 3 in deep | 4 in deep |
|---|---|---|---|
| 4 × 8 ft | 0.2 | 0.3 | 0.4 |
| 10 × 10 ft | 0.62 | 0.93 | 1.23 |
| 10 × 20 ft | 1.23 | 1.85 | 2.47 |
| 12 × 24 ft | 1.78 | 2.67 | 3.56 |
| 20 × 20 ft | 2.47 | 3.7 | 4.94 |
| 20 × 30 ft | 3.7 | 5.56 | 7.41 |
| 30 × 40 ft | 7.41 | 11.11 | 14.81 |
Common mistakes
- Multiplying inches as if they were feet. 4 in of depth is 0.33 ft, not 4; mixing them makes the answer 12 times too big.
- Ordering the exact volume. Loose soil and mulch settle after spreading, and suppliers sell in half or whole yards, so round up.
- Using the diameter as the radius for a round bed. Halve it first.
- Assuming a yard weighs the same for every material. A yard of gravel is far heavier than a yard of mulch; check weight limits before loading a truck.
Frequently asked questions
How do I calculate cubic yards?
Multiply length × width × depth with every measurement in feet, then divide by 27, because a cubic yard is 3 ft × 3 ft × 3 ft = 27 cubic feet.
How much area does one cubic yard cover?
One cubic yard covers 324 sq ft at 1 inch deep, 162 sq ft at 2 inches, 108 sq ft at 3 inches and 81 sq ft at 4 inches.
How many cubic feet are in a cubic yard?
27. Bagged products are often sold in cubic feet (2 or 3 cu ft bags), so 1 cubic yard equals 13.5 bags of 2 cu ft or 9 bags of 3 cu ft.
How heavy is a cubic yard?
It depends on the material: about 1.4 tons for gravel, around 1 ton for topsoil and well under half a ton for mulch. Use the gravel calculator for tonnage.
How many cubic yards for a 4 × 8 ft raised bed?
At 12 in deep, it holds 32 cu ft, about 1.19 cubic yards.
How many cubic yards for 1,000 sq ft at 3 inches deep?
About 9.26 cubic yards (250 cu ft), for example a 20 × 50 ft area.
How many cubic yards for a 10 × 10 ft area 6 inches deep?
About 1.85 cubic yards (50 cu ft).
How do I convert cubic feet or cubic meters to cubic yards?
Divide cubic feet by 27, so 100 cu ft is 3.7 cubic yards. Multiply cubic meters by 1.308.
Sources
Formulas and defaults last reviewed October 30, 2026. How we check our math.