United States Soil
Calculate soil from a few simple inputs in the United States.
About United States Soil
Filling a bed needs volume, and it needs more volume than the raw dimensions suggest. Area times depth (with the depth converted from inches to feet) gives the finished cubic footage, but a fresh soil blend compacts once watered and worked, so a settling allowance of 10 to 20 percent is added before you order. Dividing by 27 converts to the cubic yards a bulk supplier sells in. The result is then split by your compost share, because good bed mix is not pure topsoil: roughly 60 to 70 percent screened topsoil with 30 to 40 percent compost gives structure and drainage plus the organic matter that holds nutrients and moisture.
Formulas
Finished bed volume
finished cu ft = planting area (sq ft) x fill depth (in) / 12
Order volume with settling
order cu ft = finished cu ft x (1 + settling%)
Blend split
compost cu yd = total cu yd x compost%; topsoil = remainder
Worked example
With the default values below, United States Soil returns Soil to Order of 8.52. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Area to fillaccepts 1–100,000 sq ft
- 300 sq ft
- Fill depthaccepts 1–36 in
- 8 in
- Compost share of the blendaccepts 0–100 %
- 30 %
- Settling allowanceaccepts 0–40 %
- 15 %
Results
- Soil to Order
- 8.52 cu yd
- Topsoil Portion
- 5.96 cu yd
- Compost Portion
- 2.56 cu yd
- Order Volume
- 230.0 cu ft
Step by step
- 1Values used
- 2Finished bed volume
- 3Order volume with settling
- 4Blend split
- 5Soil to Order= 8.52 cu yd
- 6Topsoil Portion= 5.96 cu yd
- 7Compost Portion= 2.56 cu yd
- 8Order Volume= 230.0 cu ft
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
Why order extra for settling?
A freshly delivered blend is fluffy with air pockets. After the first few waterings it compacts, and a bed filled exactly to the rim drops an inch or two. Ordering 10 to 20 percent extra saves a second delivery fee for a small top-up.
What is a good topsoil-to-compost ratio?
For vegetable beds, roughly 60-70 percent screened topsoil to 30-40 percent compost works well. All-compost beds hold too much water, shrink dramatically as the organic matter mineralises, and can carry nutrient levels high enough to harm seedlings.
Can I fill the bottom of a deep bed with something cheaper?
For beds deeper than about 12 inches, many gardeners fill the lower third with coarse organic material such as branches and leaves. Just remember most vegetables root in the top 8 to 12 inches, so keep that upper layer as proper blended soil.
Related Calculators
United States specifics
- Currency
- $ USDUS Dollar
- Region
- North America
- Country code
- US
- Amounts look like
- $1,234,567.89
- Dates look like
- Mar 9, 2026
- Units
- imperialWeek starts Sunday
In United States, imperial units are in everyday use.
Results on this page are expressed in USD (US Dollar). Figures are estimates for general planning — confirm current rates and thresholds with the relevant United States authority before relying on them.