Topsoil Calculator
This free topsoil calculator converts the area you’re covering and your desired fill depth into cubic feet, cubic yards, an estimated weight, and a bag count — so you order the right amount of topsoil the first time. Enter your measurements in square feet, get the answer in yards, and this topsoil estimator works whether you’re topdressing a lawn, filling a bed, or building a planter.
Cubic Yards = (Length × Width × Depth in feet) ÷ 27. A 20×10 ft bed filled 4 inches deep needs about 2.47 cubic yards before any project-specific allowance. Enter your own square footage and depth below for an exact figure in yards, cubic feet, weight, and bags.
Area × Depth ÷ 27 = Cubic YardsHow to Use This Topsoil Estimator
Three inputs, in either shape mode, get you an order-ready number.
Measure your area
Choose rectangular or circular, then enter length and width, or diameter, in feet. This is where “topsoil calculator square feet” comes in — square footage is the starting point either way.
Set your fill depth
Enter the depth in inches, or tap a preset for common jobs — top-dressing, a new lawn, a raised bed, or a deep planter.
Read cubic yards, weight, and bags
The topsoil calculator in yards format is what most bulk suppliers quote — cross-check it against the bag count if the job is small enough to skip a bulk delivery.
Why Use a Topsoil Calculator Before You Order
Topsoil is sold by volume, but most people think about a project in terms of area and depth — a 20-by-10-foot bed, filled 4 inches deep. A calculator for topsoil bridges that gap automatically, converting square footage and fill depth into the cubic feet and cubic yards that bulk suppliers actually quote, then estimating weight so you know what a delivery truck or trailer is really carrying.
Guessing on quantity tends to go one of two ways: ordering too little and paying for a rushed second delivery mid-project, or ordering too much and being stuck disposing of leftover soil. This top soil calculator also builds in a bag-count conversion for smaller jobs, since many home-improvement stores sell topsoil in roughly 0.75-cubic-foot bags rather than by the yard — useful when a project is too small to justify a bulk delivery minimum.
Whether you’re topdressing a lawn the way university turfgrass programs recommend, filling a new garden bed, or building out a raised planter, this topsoil estimator works through the same area-times-depth math every time, with a shape option for both rectangular and circular areas like tree rings or round beds.
How the Topsoil Calculator Works, Step by Step
This topsoil calculator follows the same volume math used in university extension topdressing guides: find the area, apply the fill depth, then convert to the units your supplier actually sells by.
Rectangular area
Volume = Length × Width × Depth, with depth converted from inches to feet by dividing by 12.
Circular area
Volume = π × (Diameter ÷ 2)² × Depth — useful for tree rings, circular beds, or planters.
Cubic feet to cubic yards
Cubic Yards = Cubic Feet ÷ 27, since a cubic yard is 3 ft × 3 ft × 3 ft. Bulk suppliers almost always price and deliver by the yard.
Weight estimate
Weight = Cubic Yards × Density ÷ 2000 — topsoil density varies with moisture and composition, so treat this as an estimate, not a scale-verified figure.
Choosing a Topsoil Depth
Depth depends on the job. Use project-specific guidance rather than treating one table as universal.
Existing lawns
UW–Madison Extension describes lawn topdressing as a thin soil layer, usually no more than about ¼–½ inch, and notes that the topdressing material should be compatible with the underlying soil.
New lawn preparation
UW–Madison Extension recommends working quality soil and/or organic matter into the existing soil to a depth of about 4–6 inches when preparing a new lawn site. That is preparation guidance, not a universal instruction to place 4–6 inches of imported topsoil on every site.
Garden beds and planters
Required depth depends on existing soil, plant root requirements, drainage, bed construction, and whether you are amending soil or filling a container. Follow the project or plant guidance appropriate to the site.
Supplier quantities
For any chosen depth, this calculator converts area × depth into cubic feet and cubic yards. The volume math is independent of which depth you decide is appropriate.
Topsoil Calculator: Worked Examples
Three examples using the same area-times-depth formula as the calculator.
Rectangular bed
Circular planting area
Thin lawn topdressing
Topsoil Calculator Mistakes to Avoid
Mixing up cubic feet and cubic yards
Bagged topsoil is usually priced per cubic foot, while bulk delivery is priced per cubic yard (27 cubic feet). Ordering the wrong unit is the single most common way people under- or over-order.
Not accounting for settling
Delivered soil can settle or compact, but the amount varies with material, moisture, handling, and placement. If the finished grade matters, ask your supplier or landscaper whether they recommend a project-specific allowance.
Using a dry-soil weight estimate for wet soil
Soil weight varies with bulk density and moisture. If you are hauling material yourself, use a supplier-provided weight or density and stay within the vehicle or trailer manufacturer’s payload limits.
Piling too much depth directly on an existing lawn
Topdressing more than about 1/2 inch at once can smother actively growing turf instead of improving it. For thicker layers, work in stages or till the soil first, following standard turfgrass extension guidance.
Confusing topsoil with fill dirt or garden soil
Fill dirt is typically subsoil used for grading and structural fill, not planting. Garden soil is topsoil blended with organic matter. Using the wrong product — or the wrong density for it — throws off both the volume and weight estimate.
Topsoil Calculator FAQ
How much does a cubic yard of topsoil weigh?+
How do I convert square feet into cubic yards of topsoil?+
Should I order extra topsoil beyond the calculated amount?+
What’s the difference between topsoil, garden soil, and compost?+
How many bags of topsoil equal a cubic yard?+
How do I calculate topsoil for an odd-shaped or sloped area?+
Who Built This Topsoil Calculator
More Calculators Like This
Topsoil Calculator: Reference Standards
- University of Wisconsin–Madison Division of Extension. Lawn Aeration and Topdressing (Publication A3710).
- Cornell University, College of Agriculture and Life Sciences. Topdressing — Sports Field Management.
- University of Missouri Extension. Improving Lawn and Landscape Soils (Publication G6955).
- CalcsDone Methodology