Topsoil Calculator

Topsoil is a gardening and lawn material first, not a construction aggregate, and it behaves differently from the gravel or stone you'd order for a driveway — it settles more, it's sold loose, and how much you need depends heavily on what's growing in it rather than what's driving over it. This calculator converts your area and depth into cubic yards, cubic feet, and tons, using a supplier-sourced density instead of a rounded-off average. Enter the length and width of your space, pick a depth — or tap a preset for lawn topdressing, a garden bed, or a raised bed — and the results update as you type. Add a price per yard or ton and you'll get an estimated cost range too. Whether you're topping off a lawn or filling a raised bed from scratch, the numbers below are the ones to bring to the nursery or supplier.

Your area

Price (optional)

Enter your dimensions above to see results.

How it's calculated

The calculator first finds the volume of the area in cubic feet: length (ft) × width (ft) × depth (in ÷ 12). That's converted to cubic yards by dividing by 27, since a cubic yard is 3 ft × 3 ft × 3 ft. A waste percentage is added on top — higher than for aggregate, since topsoil settles more once it's watered in — and the adjusted cubic yardage is multiplied by topsoil's density (tons per cubic yard) to get the weight in tons. Bag counts divide the adjusted cubic feet by each bag's yield; truckloads divide the adjusted cubic yards by the truck's capacity.

Worked example

A 10 ft × 10 ft garden bed at 6 inches deep: volume = 10 × 10 × (6 ÷ 12) = 50 cubic feet. In cubic yards, that's 50 ÷ 27 = 1.85 yd³. Adding a 15% waste factor: 1.85 × 1.15 = 2.13 yd³. At 1.10 tons per cubic yard, that's 2.13 × 1.10 = 2.34 tons — or 1.92–3.09 tons across the full 0.90–1.45 density range, since topsoil's weight swings more than gravel or sand depending on moisture. In 1.5 cu ft bags, the adjusted 57.5 cu ft (50 × 1.15) needs 39 bags — right at the edge of where bulk delivery starts making more sense.

How deep should it be?

Topsoil depth depends on what's being planted and how established it already is, more than on any structural requirement. A 3" layer is right for topdressing — leveling low spots in an existing lawn or prepping bare, graded ground before a full reseed. That's a heavier pass than routine overseeding maintenance, which typically only needs a thin 1/4"–1/2" layer worked into the existing grass; use the 3" preset when you're correcting the lawn's surface, not just refreshing it. A 6" layer is standard for a new garden bed, deep enough for most annuals and shallow-rooted perennials. A 12" (or deeper) raised bed gives vegetables and deeper-rooted plants room to establish without hitting a hard boundary. Whatever the target, order based on the settled depth you want — topsoil is sold and delivered loose, and it compacts noticeably once it's watered in and walked on, more than gravel or sand does, which is why the waste factor here defaults higher than on the aggregate calculators.

Common mistakes

  • Confusing topsoil, fill dirt, and garden soil blends. Fill dirt is unscreened subsoil for grading, not planting; garden soil blends add compost and amendments that plain topsoil doesn't have.
  • Measuring depth as the loose delivered pile instead of the settled depth — topsoil compacts significantly once watered in and walked on, more than aggregate does.
  • Underfilling a raised bed. A 12" bed filled with only 6" of topsoil leaves roots shallow and dries out faster than a properly filled bed.
  • Topdressing a lawn too thick in one pass for routine maintenance. More than about 1/2" over existing grass can smother it — save a heavier 3" pass for leveling or full reseeding.
  • Ordering bagged topsoil for a job that's really a bulk order. Past roughly a cubic yard, bagged topsoil runs well above the per-yard cost of a bulk delivery.

Where the density figure comes from

Topsoil density varies more than aggregate because it depends on organic content, screening, and especially moisture. Ottr Landscape Supply puts typical moist topsoil or fill dirt at about 2,200 lbs (just over 1 ton) per cubic yard — the figure most landscape suppliers use for load planning — and notes saturated topsoil can weigh 30–35% more than dry. North Bay Materials lists soil at roughly 0.6–1.2 tons/yd³. Light screened blends sit near the low end of our published 0.90–1.45 range; moist loam and fill dirt sit near the high end. We use 1.1 tons/yd³ as the display figure, drawn from:

Read more in our density methodology.

FAQ

How much topsoil do I need for a raised bed?
For a 4 ft × 8 ft raised bed filled 12" deep, that's 4 × 8 × 1 = 32 cubic feet, or about 1.19 cubic yards before waste. Use the calculator above with your waste factor to get the exact bag count or bulk order, since raised beds settle noticeably in the first few waterings.
What's the difference between topsoil, fill dirt, and garden soil?
Fill dirt is unscreened subsoil used for grading and filling low spots — it's not meant to support plant growth. Topsoil is the nutrient-rich upper soil layer, often screened to remove rocks and debris. Garden soil blends start with topsoil and add compost or amendments for planting beds. Use topsoil for lawns and general planting, garden soil blends for vegetable beds, and fill dirt only for grading.
Why does topsoil weight vary so much more than gravel or sand?
Topsoil's weight depends on organic content, how finely it's screened, and above all moisture — and it holds water far more than mineral aggregates do. Ottr Landscape Supply notes saturated topsoil can weigh 30-35% more than dry. A light, well-screened blend sits near the low end of the published range; wet loam or fill dirt sits near the high end.
Should I order based on the loose or settled depth?
Settled. Topsoil compacts noticeably once it's watered in, rained on, and walked on — more so than sand or gravel. Order based on the depth you want after it settles, and let the waste factor cover the difference, or you'll find your bed or lawn a noticeable inch or two short a few weeks later.
How much topsoil should I use to topdress a lawn?
A thin refresh pass for routine overseeding is usually just 1/4"–1/2", spread to work into the existing grass rather than bury it. A heavier 3" application makes sense when leveling significant low spots or prepping bare ground before a full reseed — that's the depth this calculator's topdressing preset assumes.
Is bagged or bulk topsoil cheaper?
Bulk wins past about a cubic yard. Bagged topsoil carries packaging and handling costs that add up fast once you're buying more than a few dozen bags — a raised bed or small planting area is usually the ceiling for where bags still make sense over a bulk delivery.
How many truckloads of topsoil will I need?
Divide your adjusted cubic yardage by the truck's capacity — most standard dump trucks carry about 10-14 cubic yards. The calculator above uses 12 cubic yards as a default and rounds up, since a partial truckload still requires a full trip.

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