Dirt Volume Calculator
Use this calculator to determine how many cubic yards of dirt, soil, or mulch you'll need for your project. Simply enter the dimensions of the area you wish to fill.
Calculation Results
" + "Area Dimensions: " + lengthFeet.toFixed(2) + " ft (L) x " + widthFeet.toFixed(2) + " ft (W) x " + depthFeet.toFixed(2) + " ft (D)" + "Total Volume (Cubic Feet): " + volumeCubicFeet.toFixed(2) + " cubic feet" + "Total Volume (Cubic Yards): " + volumeCubicYards.toFixed(2) + " cubic yards" + "Buffer for Settling/Waste: " + bufferPercentage.toFixed(0) + "%" + "Total Cubic Yards Needed (with buffer): " + volumeCubicYardsWithBuffer.toFixed(2) + " cubic yards"; }How to Calculate Yards of Dirt for Your Project
Whether you're planning a new garden bed, leveling a section of your yard, or filling a trench, accurately calculating the amount of dirt, soil, or mulch you need is crucial. Ordering too little means delays and extra delivery fees, while ordering too much leads to wasted material and disposal headaches. This guide will walk you through the simple steps to determine exactly how many cubic yards of dirt your project requires.
Understanding Cubic Yards and Cubic Feet
Dirt, soil, and other landscaping materials are typically sold by the cubic yard. A cubic yard is a unit of volume equal to the volume of a cube with sides one yard (3 feet) in length. This means:
- 1 yard = 3 feet
- 1 cubic yard = 1 yard x 1 yard x 1 yard
- 1 cubic yard = 3 feet x 3 feet x 3 feet = 27 cubic feet
Therefore, to convert cubic feet to cubic yards, you simply divide the total cubic feet by 27.
The Basic Formula for Dirt Calculation
The calculation is straightforward: you need to find the volume of the space you want to fill. This is done by multiplying the length, width, and depth of the area. Ensure all your measurements are in the same unit, preferably feet, before performing the calculation.
The formula is:
Volume (Cubic Feet) = Length (feet) × Width (feet) × Depth (feet)
Once you have the volume in cubic feet, convert it to cubic yards:
Volume (Cubic Yards) = Volume (Cubic Feet) / 27
Step-by-Step Calculation Guide
- Measure the Length: Use a tape measure to find the length of the area you need to fill. Record this measurement in feet. If you measure in inches, divide by 12 to convert to feet (e.g., 6 inches = 0.5 feet).
- Measure the Width: Similarly, measure the width of the area in feet.
- Determine the Desired Depth: Decide how deep you want the dirt to be. This is a critical measurement. For topsoil, it might be 4-6 inches (0.33-0.5 feet); for a raised garden bed, it could be 1-2 feet. Convert this depth to feet.
- Calculate Cubic Feet: Multiply your length, width, and depth measurements together.
- Convert to Cubic Yards: Divide the total cubic feet by 27.
- Consider a Buffer: It's a good practice to add an extra 5-15% to your total cubic yards. This accounts for settling, compaction during delivery and spreading, and any minor miscalculations or uneven areas. For example, if you need 10 cubic yards, adding a 10% buffer means you should order 11 cubic yards.
Practical Example: Raised Garden Bed
Let's say you're building a raised garden bed with the following dimensions:
- Length: 12 feet
- Width: 4 feet
- Desired Depth: 18 inches
Here's how to calculate the dirt needed:
- Convert Depth to Feet: 18 inches / 12 inches/foot = 1.5 feet
- Calculate Cubic Feet: 12 feet × 4 feet × 1.5 feet = 72 cubic feet
- Convert to Cubic Yards: 72 cubic feet / 27 cubic feet/yard = 2.67 cubic yards
- Add a Buffer (e.g., 10%): 2.67 cubic yards × 1.10 = 2.94 cubic yards
In this scenario, you would likely order 3 cubic yards of dirt to ensure you have enough.
Tips for Accuracy
- Measure Carefully: Double-check all your measurements. Even small errors can lead to significant differences in larger projects.
- Irregular Shapes: For irregularly shaped areas, try to break them down into simpler rectangles or squares, calculate each section separately, and then add the volumes together.
- Account for Compaction: Different types of soil and fill material compact differently. If you're filling a large area that will be driven on or heavily used, you might need a slightly higher buffer percentage.
- Check with Supplier: When ordering, confirm with your supplier if their cubic yard measurement accounts for any initial compaction or if it's a loose volume.
By following these steps and using the calculator above, you can confidently determine the exact amount of dirt you need, saving you time, money, and effort on your next landscaping project.