How to use the topsoil calculator
- Pick a soil type — plain topsoil, blended garden soil or compost — since each has a different weight.
- Choose a shape (rectangle, circle, triangle or ring) and enter your area's dimensions.
- Enter the depth: 4–6 in for a lawn, 8–12 in for a raised bed.
- Covering more than one area? Press Add another area to add them together.
- Read the result in cubic yards, tons and bags, tick a waste allowance, and enter a price for an estimated cost.
Don't know the square footage yet? The square footage calculator can help you measure the area first.
How much soil do I need? The formula
Cubic yards = length (ft) × width (ft) × depth (ft) ÷ 27.
- Measure length and width in feet, and decide the depth in inches.
- Multiply length × width × (depth ÷ 12) to get cubic feet.
- Divide by 27 for cubic yards, then multiply by the soil's density for tons.
Worked example: a 20 × 15 ft lawn area topped with 5 in of topsoil: 20 × 15 × (5 ÷ 12) = 125 cu ft, ÷ 27 = 4.63 cubic yards, ×1 ton/yd³ = 4.63 tons.
Soil types and recommended depth
| Soil type | Typical density | Recommended depth | Best for |
|---|---|---|---|
| Topsoil | 1 tons/yd³ | 4–6 in | New lawns and leveling: 4–6 in deep, more for regrading low spots. |
| Garden soil (blended) | 0.65 tons/yd³ | 8–12 in | Raised beds and containers: lighter and richer than plain topsoil, 8–12 in deep. |
| Compost | 0.5 tons/yd³ | 1–3 in | Soil amendment, usually tilled into the top 1–3 in of existing soil. |
Typical, widely published values — density depends on moisture, compaction and what the soil is blended with. Ask your supplier for their exact figure, especially for a paid order.
Lawns vs. raised beds vs. leveling
How much you need, and which product, depends heavily on the job:
- New lawns: 4–6 in of plain topsoil, then seed or sod on top. The 20 × 15 ft example above needs about 4.63 cubic yards.
- Raised beds: 8–12 in of a richer blended garden soil, since plants grow entirely within the bed. An 8 × 4 ft bed at 10 in deep needs about 0.99 cubic yards.
- Leveling and grading: a thin layer, often just 1–2 in, spread over a larger area to fill low spots. A 12 × 10 ft spot at 1 in deep needs about 10 cubic feet.
- Enriching existing soil: compost tilled into the top few inches, rather than piled up separately.
A soil and compost mix for raised beds
Raised beds do best with a blend rather than pure topsoil: roughly half to two-thirds topsoil or garden soil for structure, around a third compost for nutrients, and a smaller portion of coarse sand or perlite for drainage. Run the topsoil (or garden soil) portion and the compost portion through the calculator separately with your bed's dimensions, then combine by volume — for the 8 × 4 ft, 10 in deep bed above, that's 0.99 cubic yards of garden soil versus 0.99 cubic yards if it were filled with compost alone.
Other landscaping calculators
- Topping beds with mulch after planting? Try the mulch calculator.
- Need gravel for paths between beds? Try the gravel calculator.
- Leveling a base with sand instead? Try the sand calculator.
- Just need the area, not the material? Try the square footage calculator.
Frequently asked questions
How much topsoil do I need?
Multiply the area in square feet by the depth in feet, then divide by 27 for cubic yards. A 20 × 15 ft lawn area at 5 in deep needs 125 cubic feet, or 4.63 cubic yards, of plain topsoil. The calculator above works out the same for any shape, and lets you switch between topsoil, garden soil and compost.
How much topsoil do I need for a raised bed?
Raised beds usually want 8–12 in of soil, deeper than a lawn top-dressing, since roots need room to grow without hitting the bottom of the bed. An 8 × 4 ft bed at 10 in deep needs about 0.99 cubic yards (26.67 cu ft) of a blended garden soil.
How deep should topsoil be for a new lawn?
Most new lawns get 4 to 6 in of topsoil over the existing ground before seeding or laying sod, enough to give grass roots room to establish. For touching up thin patches or overseeding, a thin layer of about 0.25 to 0.5 in is usually enough, which is a top-dressing rather than a full topsoil job, and needs far less material.
How many tons of topsoil do I need?
Tons = cubic yards × the soil's density. Plain topsoil is about 1 ton per cubic yard, so the 20 × 15 ft lawn example above (4.63 cu yd) weighs roughly 4.63 tons. Blended garden soil is lighter, at about 0.65 tons per cubic yard, because it's mixed with compost and other amendments.
What is the difference between topsoil, garden soil and compost?
Topsoil is the natural top layer of earth, mainly used to fill, level and grade — it is not very rich in nutrients on its own. Garden soil is topsoil blended with compost and other amendments, ready to plant directly into raised beds or borders. Compost is fully decomposed organic matter, used to enrich existing soil rather than to fill space on its own — it's about 0.5 tons per cubic yard, noticeably lighter than plain topsoil.
What soil and compost mix should I use for a raised bed?
A common starting mix is roughly 50–60% topsoil or garden soil, 30–40% compost, and the rest coarse material like sand or perlite for drainage — adjust for what you're growing. An 8 × 4 ft bed at 10 in deep needs about 0.99 cubic yards of soil; if you filled the same bed with pure compost instead it would take 0.99 cubic yards, since compost is lighter and settles differently. Run each material through the calculator separately, then combine by volume.
How much topsoil do I need to level a yard?
For light leveling — filling in low spots by an inch or so — the depth is small but the area can be large. A 12 × 10 ft low spot filled 1 in deep needs about 10 cubic feet (0.37 cu yd). For uneven ground, measure the deepest and shallowest points and use an average depth as a rough estimate.
Should I order topsoil by the ton or by the cubic yard?
Either works — they describe the same material once you know the density. Bulk topsoil suppliers commonly quote by the cubic yard, while some quote by the ton; use the calculator to match whichever figure your supplier uses, and always ask them to confirm their exact weight per yard before a paid order.
How many bags of topsoil do I need?
For small jobs, bagged topsoil (commonly 0.5, 0.75, 1, 1.5 or 2 cu ft bags, or sold by weight) can be more convenient than a bulk delivery. The calculator lists how many bags of each common size you need, always rounded up, plus an equivalent in 50 lb bags.
Is my data saved or sent anywhere?
Your measurements are saved only in your own browser, so they are there next time you open this page on the same device. Nothing is sent to our servers.