Cubic Yard Calculator

How to Calculate Cubic Yards

Whether you are pouring a concrete patio, filling raised garden beds with topsoil, or spreading mulch across your front yard, buying bulk materials requires knowing your project's volume in cubic yards. Ordering too little halts your project, and ordering too much wastes money. Our calculator processes length, width, and depth to instantly provide accurate volume requirements.

What is a Cubic Yard?

A cubic yard is a standard unit of volume measurement used primarily in the United States and Canada for construction and landscaping materials. Visualizing it is simple: imagine a cube where the length, width, and height are all exactly 1 yard (or 3 feet) long.

Because volume is calculated by multiplying three dimensions together (3 ft × 3 ft × 3 ft), one cubic yard is exactly equal to 27 cubic feet.

The Cubic Yard Formula

If you prefer to calculate the volume manually, the standard mathematical formula involves converting all your measurements into feet before doing the final calculation. The formula is:

Step-by-Step Manual Calculation

1. Measure your area: Find the length and width of the space you want to cover.
2. Determine the depth: Decide how thick you need the material to be. For example, mulch is typically spread 2 to 3 inches thick, while a standard concrete sidewalk is 4 inches thick.
3. Convert all measurements to feet: This is the step where most mistakes happen. If your depth is in inches, you must divide by 12 to convert it to feet (e.g., 3 inches = 3 / 12 = 0.25 feet).
4. Multiply the dimensions: Multiply Length × Width × Depth to get the total volume in cubic feet.
5. Convert to cubic yards: Divide the total cubic feet by 27.

Common Material Coverage Estimates

When you go to the hardware store, you won't always buy materials by the cubic yard. Often, materials are sold in smaller, manageable bags. Here is how a single cubic yard translates to common retail packaging:

Concrete

Pouring concrete requires precision. One cubic yard of concrete weighs approximately 4,000 pounds. To yield one cubic yard, you will need:

• About 45 bags of 80 lb concrete mix.
• About 60 bags of 60 lb concrete mix.
• About 90 bags of 40 lb concrete mix.

Pro Tip: Always add a 5% to 10% waste margin to your concrete order to account for uneven subgrades, spills, and form spreading. If you need to quickly find the prime factors of your required bag count to arrange them in perfectly even rows, check out our factor calculator.

Mulch and Soil

Bagged mulch is typically sold by volume rather than weight, usually in 2 cubic foot bags. Since there are 27 cubic feet in a yard, you need 13.5 bags (typically rounded up to 14) of 2 cu ft mulch to equal one cubic yard.

Topsoil is often sold in 40 lb bags. Depending on the moisture content and specific blend, you will generally need between 50 to 55 bags of 40 lb topsoil to equal one cubic yard.

Practical Application Example

Let's say you want to pour a new concrete patio that is 12 feet long, 10 feet wide, and 4 inches thick.

1. First, convert the 4-inch depth to feet: 4 ÷ 12 = 0.333 feet.
2. Multiply the dimensions: 12 ft × 10 ft × 0.333 ft = 40 cubic feet.
3. Divide by 27: 40 ÷ 27 = 1.48 cubic yards.

You would order 1.5 cubic yards of concrete from a ready-mix company, or purchase about sixty-seven 80 lb bags if mixing it yourself.