Cubic Yard Calculator
Calculate cubic yards from length, width and depth, or from square feet and depth, for rectangles, circles, triangles and trapezoids, with optional allowance, bags, weight and cost.
Enter your measurements in feet and inches (or metres and centimetres), pick a shape, and add more areas if the job is not one simple shape. The result shows cubic yards, cubic feet and cubic metres, with every step of the arithmetic.
The material only labels your results. It never changes the volume, and no density, waste or compaction is assumed.
Bags, weight and price (optional)
Printed on the bag. It differs between products, so none is assumed.
Ask your supplier. Densities vary by product and moisture, so none is assumed.
Material only: no delivery, tax or fees unless you include them.
Enter a size greater than zero for every dimension to calculate.
- Calculated volume
- With allowance, before rounding
This is a volume estimate from the sizes you entered, not a supplier quote. Suppliers set their own minimums, increments and units, so confirm the quantity with them.
Calculation breakdown
Total
Total (summed before rounding)
The total adds the exact values, so it can differ by a hundredth from adding the rounded numbers above.
Bag estimate
Estimated weight
Estimated material cost
How to Calculate Cubic Yards
- Measure the length, width and depth of the area, and convert each to feet (divide inches by 12).
- Multiply them together to get cubic feet.
- Divide the cubic feet by 27 to get cubic yards.
For other shapes, replace length × width with that shape's area, then multiply by the depth:
- Rectangle: area = length × width
- Circle: area = π × radius², where the radius is half the diameter
- Triangle: area = base × height ÷ 2
- Trapezoid: area = (side A + side B) × height ÷ 2, where A and B are the two parallel sides
The calculator keeps full precision throughout and rounds only the figures it displays.
Cubic Yards from Square Feet
If you already know the area, you only need the depth. Multiply the square feet by the depth in inches and divide by 324. That is the same as converting the depth to feet and dividing by 27, because 27 × 12 = 324.
The table shows the volume for 100 square feet at a few depths, and how much area one cubic yard covers at that depth. These are arithmetic results, not recommended depths for any material.
| Depth | Cubic yards in 100 ft² | Area covered by 1 yd³ |
|---|---|---|
| 1 in | 0.31 yd³ | 324 ft² |
| 2 in | 0.62 yd³ | 162 ft² |
| 3 in | 0.93 yd³ | 108 ft² |
| 4 in | 1.23 yd³ | 81 ft² |
| 6 in | 1.85 yd³ | 54 ft² |
| 12 in | 3.70 yd³ | 27 ft² |
Cubic Yard, cu yd, CY and yd³
Cubic yards are written several ways: cubic yards, cu yd, cu. yd., CY and yd³ all mean the same thing, and in everyday ordering people often just say "yards". The unit is the volume of a cube 3 feet on each side. This calculator uses "cubic yards" and "yd³" in its results.
Cubic Feet to Cubic Yards
One cubic yard is a cube 3 feet on each side, so 1 yd³ = 3 × 3 × 3 = 27 ft³. Divide cubic feet by 27 to get cubic yards, or multiply cubic yards by 27 to get cubic feet. In cubic inches, 1 yd³ = 46,656 in³ (36 × 36 × 36).
- 54 ft³ ÷ 27 = 2 yd³
- 100 ft³ ÷ 27 = 3.70 yd³
- 1 yd³ ≈ 0.765 m³, and 1 ft³ ≈ 0.0283 m³ (both exact conversions of the foot, per NIST)
Calculating Concrete Yardage
Ready-mix concrete is commonly sold by the cubic yard, so the calculation above gives the volume of the space to be filled. Whether you add an allowance, and how much, is a practical decision for you and your supplier. This calculator never adds one silently: it defaults to 0% and shows any allowance on its own line.
Bagged concrete is sold by yield per bag, which differs between products. Enter the yield printed on your bag under "Bags, weight and price" and the calculator divides the volume by it and rounds up to whole bags. Slab thickness, footing size, reinforcement and mix are engineering decisions that this tool does not make. For a concrete-specific estimate with slabs, footings, walls and columns, use the Concrete Calculator.
Gravel, Soil, Dirt, Mulch and Rock
The same calculation applies to topsoil, fill dirt, sand, gravel, crushed stone, mulch, compost and other loose bulk materials, and to concrete. For loose materials the volume of the space is the same whatever you fill it with, so choosing a material here does not change the cubic yards. What differs is how the product is sold. Some suppliers sell by the cubic yard, others by weight, and weight depends on the product and how wet it is.
If your supplier sells by weight, ask for the product's density, enter it under "Bags, weight and price", and the calculator multiplies it by the volume to estimate the weight. No density is built in, because any single figure would be wrong for many products.
Circular and Irregular Areas
For a round bed, tree ring or circular pad, choose Circle and enter either the diameter or the radius. For an area that is not a clean shape, such as an L-shaped yard or a curved garden, divide it into rectangles, triangles and trapezoids, enter each with "Add another area", and the calculator adds their volumes.
Curved edges can be approximated with a few straight-sided pieces. The more pieces you use, the closer the total gets to the true figure. Areas that vary in depth can be entered as separate areas with their own depths.
Cubic Yard Examples
Rectangle: 20 ft × 10 ft × 3 in. 3 in ÷ 12 = 0.25 ft, so 20 × 10 × 0.25 = 50 ft³, and 50 ÷ 27 = 1.85 yd³.
Square feet and depth: 100 ft² at 3 in. 100 × 3 ÷ 324 = 0.93 yd³.
Larger area: 1,000 ft² at 3 in. 1,000 × 3 ÷ 324 = 9.259, or 9.26 yd³. One cubic yard covers 108 ft² at 3 in (324 ÷ 3), and 1,000 ÷ 108 gives the same 9.26. This is the arithmetic only; the depth that suits your material and project is for you and your supplier to decide.
Circle: radius 5 ft, depth 1 ft. π × 5² = 78.54 ft², so 78.54 ft³, and 78.54 ÷ 27 = 2.91 yd³.
Several areas: a 24 × 12 ft area 4 in deep is 96 ft³ (3.5556 yd³), a 20 × 3 ft area 3 in deep is 15 ft³ (0.5556 yd³), and a triangle with an 8 ft base, 6 ft height and 3 in depth is 6 ft³ (0.2222 yd³). Together that is 117 ft³, or 4.33 yd³. Adding the individually rounded figures (3.56 + 0.56 + 0.22) gives 4.34, which is why the calculator adds exact values and rounds only at the end.
Allowance and rounding: if you add a 10% allowance to 4.3333 yd³ you get 4.7667 yd³, and rounding that up to the next 0.25 yd³ gives 5.00 yd³. The calculated volume stays 4.33 yd³; only the estimated order changes.
Frequently Asked Questions
How do I calculate cubic yards?
Convert length, width and depth to feet, multiply them to get cubic feet, then divide by 27. For example, 20 ft × 10 ft × 0.25 ft (3 inches) is 50 cubic feet, and 50 ÷ 27 is about 1.85 cubic yards.
How do I convert cubic feet to cubic yards?
Divide the cubic feet by 27, because one cubic yard is 3 ft × 3 ft × 3 ft = 27 cubic feet. To go the other way, multiply cubic yards by 27.
How many cubic yards do I need for a given number of square feet?
Multiply the area in square feet by the depth in inches, then divide by 324. For example, 100 ft² at a depth of 3 inches is 100 × 3 ÷ 324, or about 0.93 cubic yards.
How do I find the cubic yards of a circular area?
Work out the area as π × radius² (the radius is half the diameter), multiply by the depth to get cubic feet, then divide by 27. The calculator does this when you choose Circle.
How do I calculate an irregular area?
Split it into simpler shapes such as rectangles, triangles and trapezoids, enter each as its own area using "Add another area", and the calculator adds the exact (unrounded) volumes together.
Does the material I choose change the number of cubic yards?
No. Volume depends only on the shape and dimensions. The material you pick only labels the result. Weight, bag counts and price do depend on the product, so they are calculated only from the density, bag yield and price you enter.
How much extra should I order?
There is no universal figure. The calculator defaults to 0% and shows any allowance you add as a separate line, so you can see the calculated volume and the estimated order side by side. Your supplier can tell you how they measure and deliver.
What do cu yd, CY and yd³ mean?
They are all abbreviations for the same unit, the cubic yard. One cubic yard is 3 ft × 3 ft × 3 ft = 27 cubic feet. When a supplier quotes a number of "yards" of soil, gravel, mulch or concrete, it normally means cubic yards.
How many square feet does one cubic yard cover?
It depends on the depth. Divide 324 by the depth in inches: one cubic yard covers 324 ft² at 1 inch deep, 162 ft² at 2 inches, 108 ft² at 3 inches, 81 ft² at 4 inches and 54 ft² at 6 inches.
How many bags do I need?
Divide the volume in cubic feet by the volume one bag yields, then round up to a whole bag. Bag yields differ between products, so enter the yield printed on your bag or product data sheet.
Sources
- NIST Guide to the SI, Appendix B.8: Factors for Units Listed Alphabetically, National Institute of Standards and Technology (foot, cubic foot and cubic yard conversions).