Fill Dirt Calculator – Landscaping Volume Estimator
Calculate fill dirt volume and material requirements
How to Use
- Enter the length of the area to fill
- Enter the width of the area
- Enter the depth you want to fill
- Select your preferred unit system
- Click calculate to get fill dirt requirements
What Is Fill Dirt and Its Common Uses
Fill dirt is subsoil that has been stripped of organic matter such as roots, plant material, and topsoil. Because it lacks organic content, fill dirt does not decompose or shift over time, making it ideal for creating a stable base for construction and landscaping projects.
Common uses include raising elevation around foundations, filling in low spots in a yard, building up land for retaining walls, leveling ground before pouring a concrete slab, and backfilling trenches around utilities. It is not suitable for growing plants, as it lacks the nutrients found in topsoil.
How to Estimate Fill Dirt Quantities
Measure the length, width, and depth of the area you need to fill. Multiply these three dimensions together to get the volume in cubic feet, then divide by 27 to convert to cubic yards. Fill dirt is typically sold and delivered by the cubic yard.
For irregularly shaped areas, break the space into smaller rectangular sections, calculate each one separately, and add them together. If the depth varies across the area, use the average depth for a more accurate estimate.
Compaction and Settling
Loose fill dirt contains air pockets that reduce in size over time or when mechanically compacted. Proper compaction is essential for any area that will support a structure, driveway, or walkway. Without compaction, settling can cause uneven surfaces and structural damage.
Apply fill dirt in lifts (layers) of 6–8 inches and compact each layer with a plate compactor or jumping jack before adding the next. This method achieves 90–95% compaction density and minimizes future settling. Always order 10–15% more material than calculated to account for compaction loss.
Frequently Asked Questions
- What is the difference between fill dirt and topsoil?
- Fill dirt is subsoil with no organic matter, making it stable and ideal for structural support. Topsoil is the nutrient-rich upper layer of soil used for planting and gardening. Never use topsoil as structural fill — its organic content decomposes over time, causing settling and instability.
- How much will fill dirt settle after placement?
- Uncompacted fill dirt can settle 20–30% over time. Properly compacted fill dirt in 6–8 inch lifts settles very little, typically less than 2–3%. For best results, use mechanical compaction equipment and allow the fill to sit for a few days before building on top of it.
- What should I know about fill dirt delivery?
- Fill dirt is delivered by dump truck, and a standard truck holds 10–14 cubic yards. Ensure the delivery truck has access to your site with a path at least 10 feet wide. Consider where the dirt will be dumped — placing it close to the fill area reduces the amount of wheelbarrow work required.
- What factors affect the cost of fill dirt?
- The main cost factors are the volume needed, distance from the source, and local availability. Fill dirt is one of the cheapest bulk materials, but delivery fees can add significantly to the total cost, especially for small orders or long haul distances. Some excavation projects offer free fill dirt if you arrange pickup.