Outdoor, Deck & Fence
Topsoil Calculator
Cubic yards of topsoil for lawns, raised beds and grading, with settling allowance.
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Results
Adjust the inputs to see your result.
About this calculator
Loose topsoil settles and compacts by roughly 20% once spread and watered, so the delivered volume must exceed the finished volume. This calculator applies that allowance and converts the result into bulk yards or 1.5 cu ft bags for smaller beds.
What this number means
Topsoil is ordered loose and judged finished — and those are different volumes. A delivered yard is fluffy, full of air; spread it, roll it and water it, and roughly a fifth of it disappears into compaction. This calculator therefore reports two volumes: the finished depth you designed, and the loose quantity you must actually order to still have that depth in a month.
Skipping the settling allowance is the classic topsoil mistake: the lawn looks perfect on day one and is an inch low everywhere by the first rain, with the edges of paths and patios suddenly standing proud.
The formula
- Finished volume = Area (sq ft) × Depth (in) ÷ 324, in cubic yards
- Loose volume to order = Finished volume × (1 + settling %) — 20% is the standard allowance
- Bags = Loose volume in cu ft ÷ bag size, rounded up
- Weight ≈ Loose cu yd × 1.1 tons (screened topsoil, typical moisture)
Worked example
Topdressing and levelling a 20 × 30 ft lawn area at 4 in finished depth.
- Finished volume = 600 × 4 ÷ 324 = 7.41 cu yd
- Loose to order = 7.41 × 1.20 = 8.89 cu yd → order 9 cu yd
- That is roughly 9.8 tons — a single tri-axle delivery for most suppliers
- Bagged equivalent: 240 loose cu ft ÷ 1.5 = 160 bags — bulk wins at this scale, every time
Assumptions and limitations
- The settling allowance covers compaction of the soil itself. It does not cover an unprepared subgrade sinking, or soil washing into voids — grade and compact the base first on new lawns.
- Raised beds settle more in year one as the mix's organic fraction decomposes; filling to the brim and topping up next season is normal, and a 25% allowance is defensible there.
- Weight assumes typical screened topsoil at field moisture. Saturated soil can weigh 1.3 tons per yard or more — relevant if you are self-hauling with a small trailer.
- Topsoil depth for seeding is measured after grading. If you are also removing sod or existing soil, the dig-out volume is a separate (larger) number.
Frequently asked questions
Budget 4–6 in of finished depth over prepared subgrade, plus 20% for settling. For 600 sq ft at 4 in that is 9 loose cubic yards to order. Shallower than 4 in and grass roots hit subgrade in the first dry summer.
Because delivered soil is loose. Spreading, rolling and watering compact it by about a fifth, so a load ordered at exactly the finished volume finishes about 20% low. The calculator applies that allowance to the order quantity, not the design depth.
Eighteen 1.5 cu ft bags (27 ÷ 1.5), or 27 one-cubic-foot bags. Beyond about 2 yards, bagged soil costs several times the bulk price and generates a pile of plastic — bulk delivery is the right call at lawn scale.
About 1.1 tons (2,200 lb) for screened topsoil at typical moisture; saturated soil can reach 1.3–1.4 tons. A standard pickup bed holds roughly 1.5–2 cu yd by volume but is usually weight-limited first.
Most vegetables want 12–18 in of soil depth; 12 in suits salads and herbs, 18 in suits root crops and tomatoes. Beds settle more than lawns as organic matter decomposes, so fill to the brim and expect to top up an inch or two next season.