How to Figure Out How Many Yards of Dirt You Need

If you are planning to fill a garden bed, level a yard, build up a planting area, or complete a landscaping project, knowing how many yards of dirt you need can help you order the right amount without wasting money.

The easiest way is to calculate the volume of the area in cubic yards.

Step 1: Measure the Area

For a rectangular or square area, measure:

Length in feet
Width in feet
Depth in inches

For example, suppose your garden area is 20 feet long, 10 feet wide, and you want to add 6 inches of dirt.

Step 2: Convert the Depth to Feet

Because your measurements are in feet, convert the depth from inches to feet:

6 inches ÷ 12 = 0.5 feet

So the required depth is 0.5 feet.

Step 3: Calculate Cubic Feet

Use this formula:

Length × Width × Depth = Cubic Feet

For the example:

20 × 10 × 0.5 = 100 cubic feet

Step 4: Convert Cubic Feet to Cubic Yards

There are 27 cubic feet in one cubic yard, so divide by 27:

100 ÷ 27 = 3.7 cubic yards

You would need approximately 3.7 cubic yards of dirt.

Quick Formula

You can use this formula for most rectangular areas:

Cubic Yards = Length × Width × Depth (in feet) ÷ 27

If your depth is measured in inches:

Cubic Yards = Length × Width × Depth (in inches) ÷ 324

For irregularly shaped areas, divide the space into smaller rectangles or sections, calculate each section separately, and add the results together.

It is also common to order a little extra dirt to account for settling, uneven ground, or measurement differences. For an easy calculation, use a Dirt Calculator to estimate how many cubic yards you need before ordering.