Bulk materials
Soil Calculator
Work out soil volume for any planting area, then see it costed as bags and as bulk. Handles rectangular beds, curved borders, circles, and irregular shapes built from sections.
Updated
Area to cover
Add a section for each part of the space. Odd shapes are easiest as two or three simple ones.
Area = length × width
Material and depth
6–8 in for annuals, 12 in or more for perennials, shrubs, and root crops.
5% covers settling and uneven ground. Use 10% on rough or sloped sites.
Only affects the weight figures, never the volume. Typical range 1200–2000 lb/cu yd, wet material sits at the top.
Enter your measurements to see results.
Build me a soil plan
Describe what you're planting and the assistant will suggest a soil blend, depth, and amendment list for your beds.
Written by AI from the figures above. The quantities themselves are calculated deterministically and are never generated by AI. Check anything consequential, permits, utility locates, and chemical labels especially, before acting on it.
How this is calculated
The calculation
Soil volume is area times depth, the same as any bulk material. The judgement call is depth, and for soil, depth should follow root depth rather than a habit.
Shallow-rooted annuals and most groundcovers are content in 6 to 8 inches. Perennials and shrubs want 12 or more. Root vegetables want depth matched to the crop: carrots and parsnips need a genuinely loose 12 inches or they fork.
cubic feet = area in sq ft × (depth in inches ÷ 12)
Choosing the right product
The three products are not interchangeable, and the price gap between them is large. Screened topsoil is the cheapest way to move volume, but it is a base material, it needs compost worked in before it grows much.
Garden soil is topsoil already amended, sold ready to plant. It is the sensible default for filling a bed you want to plant this weekend.
Potting mix is a container product. It is peat and bark and perlite with little to no mineral soil, which makes it light, fast-draining, and expensive. Filling a bed with it costs several times what garden soil costs and gives you a bed that dries out constantly.
| Product | Best for | Typical bulk price / cu yd |
|---|---|---|
| Screened topsoil | Volume fill, grading, lawn prep | $25–50 |
| Garden soil | Planting beds ready to use | $40–75 |
| Raised bed mix | Raised beds and vegetable beds | $55–110 |
| Potting mix | Containers only | $90–180 |
Worked example
A curved perennial border
A border averaging 4 ft deep along a 22 ft curve, filled 10 inches deep with garden soil.
- Area
- 22 ft × 4 ft ≈ 88 sq ft
- Depth in feet
- 10 in ÷ 12 = 0.833 ft
- Volume
- 88 × 0.833 = 73 cu ft
- Cubic yards
- 73 ÷ 27 = 2.7 cu yd
- 1.5 cu ft bags
- 73 ÷ 1.5 = 49 bags
About 2.7 cubic yards. At 49 bags and roughly $8.50 each that is $415 bagged, against $110–200 delivered in bulk, a clear win for bulk at this size.
Frequently asked questions
Related calculators
Topsoil Calculator
Topsoil is heavy, roughly a ton per cubic yard, so knowing the weight matters as much as the volume. Enter your area and depth for yards, bags, and delivered tonnage.
OpenCompost Calculator
Compost gets applied far thinner than mulch or soil, and the right depth depends entirely on the job. Enter your area and pick the application to get volume, bags, and cost.
OpenRaised Bed Soil Calculator
Enter your bed dimensions to get total fill volume and a mix breakdown. Raised beds swallow far more soil than people expect, a single 4 × 8 ft bed at 12 inches deep takes nearly 32 cubic feet.
OpenMulch Calculator
Enter your bed dimensions and how deep you want the mulch. You'll get cubic yards, the number of 2 cu ft bags, delivered weight, and whether bags or bulk works out cheaper at that volume.
OpenGuides that go deeper
- Shade Garden Winners: Shrubs, Perennials, and Groundcovers That WorkShade gardening is all about matching the right plant to the right spot. Here’s how to pick shrubs, perennials, and groundcovers that actually thrive in your yard’s shade.
- Winterizing Your Garden: What Actually MattersWinter garden prep isn’t about wrapping everything in burlap. Here’s what actually matters for healthy beds, roses, and irrigation,plus what you can skip.
- Real Plants for a Goth Garden: Near-Black Flowers and Dark Foliage That Actually WorkNo flower is truly black, but you can build a goth garden with near-black blooms, dark foliage, and the right design tricks. Here’s what actually works.
- Flower Vines for Your Yard: What Works, What Wrecks, and What to SkipNot all flower vines are friendly. Here’s how to pick the right climbers for your yard, match them to supports, and dodge invasives and home damage.