Free topsoil calculator
Estimate the topsoil for any garden bed, lawn or raised bed: enter the area and depth to get cubic yards, tons and 40 lb bags, with a settling margin and bed-depth guidance — updated live, as you type.
On this page15 sections
| Order method | With 10% margin | Round up to |
|---|---|---|
| By volume | 4.07 cu yd | 4.50 cu yd |
| By weight | 4.95 tons | 9,900 lb |
| By the bag (40 lb) | 147 bags | 147 bags |
Weight uses dry / screened topsoil at 90 lb/ft³. A cubic yard of dry topsoil weighs about 2,430 lb (over a ton), so a half-ton pickup carries roughly half a yard — order a delivery for more. About 36 of the 40 lb bags fill one cubic yard.
Topsoil density varies with type and moisture. How accurate is this?
Results are estimates. Consult a professional.
How the topsoil calculator works
Topsoil is sold by volume (the cubic yard), by weight (the ton) and, for small jobs, by the bag — so the calculator works out all three from the same measurements. It multiplies the area of your bed by the depth you want to fill to get a volume in cubic feet, converts that to cubic yards (the unit most bulk suppliers quote), and multiplies the volume by topsoil's bulk density to get the weight in pounds and tons. Enter a length and width for a rectangular bed, or a diameter for a round one.
What the result actually means
Three numbers do the work. The cubic-yard figure is what you tell a bulk supplier when you order topsoil delivered. The tonnage is what a yard weighs on the scale, the way topsoil is often priced and what tells you whether a load fits your trailer. The bag count is for small beds where bulk delivery is not worth a trip charge. The calculator shows all three — and it adds a margin on top, because fresh topsoil settles and compacts after watering, so the loose volume you order shrinks once it is in the bed.
What goes into your topsoil estimate
A topsoil estimate is built from three pieces: the bed area, the fill depth and the density. Get each one right and the order is right; miss one and you are either short mid-project or paying to spread a pile you did not need.
Area — the footprint of the bed
Length times width for a rectangular bed, or π × radius² for a round one. This is the footprint you are covering. It is the easy part to measure, but it is worth measuring twice on an irregular garden — splitting an odd shape into rectangles and adding them up beats guessing on a curved border.
Depth — the lever that moves the order most
Depth is the input you choose, and it scales the whole order. A 2-inch topdressing over a lawn and a 12-inch fill in a raised bed over the same footprint differ by a factor of six in both volume and weight. Decide the depth your project actually needs before you order, because every extra inch adds soil across every square foot at once.
Density — what turns volume into weight
Volume tells you how much space the topsoil fills; density tells you what it weighs. Dry, screened topsoil is about 90 pounds per cubic foot, so a cubic yard weighs roughly 2,430 pounds — a little over a ton. Wet or clay-heavy topsoil carries water and packs tighter, pushing density past 110 pounds per cubic foot, which is why the same pile weighs noticeably more after rain.
A worked example using the topsoil calculator
Sam is filling a 10 ft × 20 ft garden bed with screened topsoil to a 6-inch depth for vegetables. He wants the volume to order by the yard, the weight so he knows whether it fits in his trailer, the bag count as a fallback, and a 10% margin for settling.
Step 1 — Find the volume in cubic feet
Depth in feet first: 6 in ÷ 12 = 0.5 ft. Then 10 × 20 × 0.5 = 100 cu ft.
Step 2 — Convert to cubic yards
100 ÷ 27 = 3.70 cu yd. That is the bare volume of the bed, before any settling.
Step 3 — Convert volume to weight
At 90 lb/ft³ for dry screened topsoil, 100 × 90 = 9,000 lb, and 9,000 ÷ 2,000 = 4.50 tons. That is past a light trailer's limit, so Sam orders a bulk delivery.
Step 4 — Add the settling margin and count bags
With 10% added, 4.50 × 1.10 = 4.95 tons (about 4.07 cu yd). As bags, 100 ÷ 0.75 = 134 bags bare, or 147 with the margin — far past the point where bulk delivery wins.
How much topsoil do I need?
If you just want a ballpark before you measure, this table gives the volume, dry weight and 40 lb bag count for common bed sizes at a 6-inch depth. These are bare figures — add 10% for settling before you order, and scale up directly if your depth is greater.
| Bed (6 in deep) | Cubic yards | Dry weight (tons) | 40 lb bags |
|---|---|---|---|
| 4 ft × 4 ft | 0.30 | 0.36 | 11 |
| 8 ft × 4 ft | 0.59 | 0.72 | 22 |
| 10 ft × 10 ft | 1.85 | 2.25 | 67 |
| 10 ft × 20 ft | 3.70 | 4.50 | 134 |
| 20 ft × 20 ft | 7.41 | 9.00 | 267 |
| 30 ft × 30 ft | 16.67 | 20.25 | 600 |
All figures assume a 6-inch depth and dry screened topsoil at 90 lb/ft³ (≈ 1.22 tons/yd³); bags are 40 lb ≈ 0.75 ft³. Halve the depth to halve the numbers; wet or clay topsoil weighs about 20% more.
How deep should topsoil be?
Depth is where a topsoil order is won or lost, because it scales the whole job — and the right depth depends entirely on what you are growing. This is the question generic soil calculators skip. The table below pairs the common landscaping jobs with the depth each one wants, so you can set the calculator to the number that actually fits your project.
| Project | Topsoil depth | Why |
|---|---|---|
| New lawn / overseeding | 4–6 in | Grass roots stay in the top few inches; 6 in gives a healthy root zone |
| Topdressing an existing lawn | ¼–½ in | A thin screened layer to level low spots without smothering the grass |
| Flower beds and borders | 6–8 in | Enough loose soil for annuals, perennials and shallow-rooted shrubs |
| Vegetable garden (in-ground) | 8–12 in | Most vegetables; deep-root crops like carrots and parsnips want the full 12 in |
| Raised garden bed | 12–18 in | Bottomless beds need depth for roots; 16–18 in suits tomatoes and root crops |
| Sod or seed over poor soil | 2–4 in | A fresh screened layer over compacted or rocky native ground |
Depths follow common landscaping and university-extension guidance for lawns, gardens and raised beds. Deep-rooted vegetables and intensive raised beds sit at the higher end of each range.
One rule cuts through it: match the depth to the root, not the plant above ground. Lettuce and herbs are happy in 6 inches; tomatoes and carrots want a foot or more. Set the depth before you read the order, because it is the single biggest driver of how much topsoil you buy.
Topsoil vs garden soil vs compost
The volume math is the same for any soil, but which one you buy depends on the job. "Topsoil," "garden soil" and "compost" are not interchangeable, and ordering the wrong one is a common and expensive mistake.
| Material | Best for | Note |
|---|---|---|
| Screened topsoil | Lawns, filling and leveling beds, sod base | Sifted to remove rocks and clumps; the general-purpose fill this calculator assumes |
| Unscreened / fill topsoil | Bulk filling, regrading, low spots | Cheaper but lumpy, with rocks and roots; not for a finished planting surface |
| Garden soil / mix | Flower and vegetable beds | Topsoil blended with compost for nutrients; richer and pricier than plain topsoil |
| Compost | Amending and enriching existing beds | Decomposed organic matter; mixed into soil, not used alone as a bed |
Density varies only slightly between these for estimating; the calculator's dry/wet setting captures the main weight difference. Confirm the product for your specific bed.
For a new vegetable bed, many gardeners fill the bulk with screened topsoil and blend compost or a garden mix into the top several inches — topsoil gives structure and volume, compost gives nutrients.
Cubic yards or tons: how topsoil is sold
Topsoil is quoted both ways, and the bridge between them is density. Bulk yards sell by the cubic yard for delivery; many sell by the ton off a scale. Knowing how the two convert lets you compare prices and confirm a load fits your vehicle.
| Topsoil condition | lb / ft³ | lb / yd³ | Short tons / yd³ |
|---|---|---|---|
| Dry, screened | 90 | ~2,430 | ~1.22 |
| Wet or clay-heavy | 110 | ~2,970 | ~1.49 |
A US short ton is 2,000 lb. Dry screened topsoil ≈ 1.0–1.3 tons/yd³ (Inch Calculator); bulk screened topsoil is quoted near 2,410 lb/yd³ (1.21 t/yd³). Wet or clay topsoil carries water and packs tighter, so the same volume weighs more.
Bulk-supplier figures for screened and shredded topsoil run about 2,410 lb/yd³ (1.21 short tons/yd³), confirming the dry-screened density this calculator uses.One practical consequence: a half-ton pickup is rated for roughly a half-cubic-yard of topsoil, not a full yard. A cubic yard of dry topsoil weighs about 2,430 pounds — over a ton — so order a delivery rather than overloading a light truck.
Waste and settling: how much extra to order
Order the exact calculated volume and you will come up short, because topsoil settles. Fresh, loose soil is full of air; once you water it and it beds in over the first few weeks, it compacts below the loose volume you ordered. Some is also lost to spillage and to an uneven base that swallows extra in the low spots. A modest overage covers all of it.
The 10% settling rule
For most beds, add 10%. On a clean, level base with screened soil you can trim that to 5%; over rough or compacted ground, or where the soil will be tamped, 10% is the floor and some gardeners go to 15%. The calculator's waste field defaults to 10% and adjusts up to 20%.
Why running short is worse than running over
Leftover topsoil is cheap and easy to use elsewhere in the garden, but running out mid-project is costly: a second small delivery often carries the same trip fee as the first, and a bed filled in two batches can settle unevenly and leave a visible dip. The overage exists so one delivery finishes the bed.
Topsoil definitions
How accurate is this topsoil calculator?
The volume math is exact. Length times width times depth, divided by 27, is the precise cubic-yard volume of your bed, and the round-bed option uses the exact π × radius² formula. If your measurements are right, the geometry is right to the decimal.
The weight and bag count are well-grounded estimates. Topsoil's bulk density varies with organic content, mineral make-up and — most of all — moisture: dry, screened topsoil sits near 90 lb/ft³ (about 1.2 tons/yd³), while wet or clay-heavy topsoil can reach 110 lb/ft³ or more. The calculator's dry/wet setting captures that swing, but the real tonnage of your specific soil can drift either way, and bag yields differ a little by brand. Treat the weight and bag count as planning figures, confirm whether your supplier sells by the yard or the ton, and when in doubt order to the high side — the settling margin exists precisely because a second small delivery costs far more per pound than the topsoil you did not need.
Frequently asked questions about the free topsoil calculator
About this topsoil calculator
This topsoil calculator runs entirely in your browser — nothing you enter is sent anywhere or stored. Set the bed shape, area, depth and topsoil type and the volume, weight and bag count recompute instantly, so you can compare ordering by the cubic yard, by the ton or by the bag before you buy.
It is one of the landscaping and building estimators in our construction calculators collection. Browse the full set of free tools on the calculators home page.