Topsoil Calculator
Topsoil settles as it beds in, so it's common to order about 10 percent extra to cover the compaction.
Topsoil weighs about 2,160 pounds per cubic yard, so a 10 by 10 foot bed at 2 inches deep needs roughly 0.62 cubic yards, or about 23 forty-pound bags. Set your bed shape, dimensions, and depth below for exact cubic yards, bag counts, and cost — and see whether bulk delivery or bags works out cheaper for your job.
Standard Soil Coverage Baselines
| Garden area | Cubic yards | 40 lb bags |
|---|---|---|
| 10 ft x 10 ft Area | 0.62 Yards | 23 Bags |
| 20 ft x 20 ft Area | 2.47 Yards | 89 Bags |
| 10 ft Circular Diameter | 0.48 Yards | 18 Bags |
| 20 ft Circular Diameter | 1.94 Yards | 70 Bags |
How to estimate topsoil
Estimating topsoil comes down to three measurements in the same units. Mixing a depth in inches with a bed measured in feet throws the whole figure off, so convert everything before you multiply.
From footprint to cubic yards
Cubic yards tell you how much three-dimensional space the soil fills, and it's the unit most suppliers price bulk deliveries in. Multiply length by width by depth to get the volume, then convert to cubic yards. The calculator does the conversion for you.
Bags vs bulk
Buying topsoil by the bag costs more per yard once you add packaging and retail markup. A standard 40-pound bag holds 0.75 cubic feet, so it takes 36 bags to equal one cubic yard of bulk delivery. For larger jobs, a bulk drop is usually the cheaper route.
Yards, tons, and bags
Suppliers quote topsoil three ways and the calculator reports all of them. Cubic yards is the volume you're filling and the safest unit to order by. Tons is a weight — a cubic yard of dry topsoil runs about 2,160 pounds, so multiply cubic yards by roughly 1.08 for tons. Bags are the retail unit at 36 forty-pound bags per cubic yard. When a yard sells by weight, remember that wet soil weighs more per yard, so you get less volume per ton than the dry figure implies.
How deep to spread topsoil
Depth is the input that decides your order, and the right depth depends entirely on the job — the same footprint can need three times the soil depending on what you're doing. Set the depth field above to match your use:
- Topdressing an existing lawn: ¼ to ½ inch. A thin skim to level low spots and feed the turf — never bury living grass more than about half an inch at a time or you'll smother it.
- Establishing a new lawn from seed: 4 to 6 inches of good soil over the subgrade gives roots room to establish. This is the depth most new-lawn jobs are sized to.
- Laying sod: 3 to 4 inches of screened topsoil, raked smooth and firmed. Sod roots into the top couple of inches, so an even, debris-free surface matters more here than raw depth.
- Raised garden beds: 8 to 12 inches, or the full interior height of the bed, so vegetable roots have depth. This is far deeper than a lawn job, which is why a small raised bed can swallow more soil than a large lawn topdressing.
Screened vs. unscreened topsoil
Topsoil is sold in two forms, and the difference is processing, not the soil itself. Screened topsoil is run through a mesh — commonly a ½-inch to ¾-inch screen — to remove rocks, roots, sticks, and clumps, leaving a fine, uniform product that rakes and levels cleanly. Unscreened topsoil is the raw material dug straight from the ground: it holds the same nutrients but comes lumpy and full of debris.
Use screened topsoil where the finish shows or roots are shallow — seedbeds, sod, raised beds, and lawn work. Unscreened is cheaper and fine for bulk fill, backfill, and rough grading where a clean surface doesn't matter. Both estimate identically here, since screening changes the texture, not the volume you need to fill a bed. A finer ½-inch screen suits garden and seedbed work; a ¾-inch screen is slightly coarser but still fine for lawns.
For an irregular bed the calculator's rectangle and circle shapes don't cover, split the area into simple sections, run each, and add the cubic yards — the same approach that works for any odd footprint.
About these figures: the weight-per-cubic-yard basis (about 2,160 lb, or 1.08 tons) follows the published topsoil weight range cited below, and bulk density varies with moisture and composition. Depth ranges are standard landscaping and horticultural practice; screening sizes (½-inch to ¾-inch mesh) reflect common supplier grades. Confirm delivered weight and grade with your local supplier, since soil varies by region and season.
Frequently asked questions
How do you calculate how much topsoil is needed?
Measure the square footage of the area you're covering and multiply it by the depth you want to spread, then convert to cubic yards. Enter your dimensions and depth above and the calculator handles the conversion for you.
How many bags of topsoil are in a cubic yard?
You need 36 bags to make one cubic yard, assuming the common 40-pound bag that holds 0.75 cubic feet. There are 27 cubic feet in a cubic yard, so dividing 27 by 0.75 gives you 36 bags.
How much does a cubic yard of topsoil weigh?
Dry topsoil averages about 2,160 pounds per cubic yard, or roughly 1.08 tons. If the soil is wet from recent rain, the added water weight can push it past 2,500 pounds, so factor that in when checking what your vehicle can carry.
Is it cheaper to buy topsoil by the yard or by the bag?
Bulk delivery is cheaper for larger jobs because bagged topsoil carries extra packaging and retail markup. For anything over roughly 1.5 cubic yards (about 54 bags), a bulk dump-truck delivery usually costs less than buying bags.
How thick should topsoil be spread?
Spread 4 to 6 inches for seeding a new lawn so roots have enough depth to establish. For topping up an existing garden bed, 2 inches is usually enough.
Does topsoil settle over time?
Yes. Topsoil compresses under foot traffic and rain over the first several months. Ordering 10 to 15 percent extra volume covers the settling so you don't come up short after it beds in.
How do I convert topsoil from cubic yards to tons?
Multiply cubic yards by about 1.08 to get tons of dry topsoil, since a cubic yard weighs roughly 2,160 pounds. So 5 cubic yards is close to 5.4 tons. Wet soil weighs more — up to 2,500 pounds or so per yard — so if a supplier sells by the ton and the soil is damp, you'll get slightly less volume per ton than the dry figure suggests. Order by the cubic yard when you can, since that's the volume you're actually filling.
What is the difference between screened and unscreened topsoil?
Screened topsoil is run through a mesh — usually a ½-inch to ¾-inch screen — to pull out rocks, roots, sticks, and clumps, leaving a fine, uniform soil that's easy to rake and level. Unscreened topsoil is the raw material straight from the ground, cheaper but lumpy and full of debris. Use screened for lawns, seedbeds, and raised beds where you want a clean finish; unscreened is fine for bulk fill and rough grading where looks don't matter. Both estimate the same by volume.
How much topsoil do I need for a raised garden bed?
Fill a raised bed to its full working depth, which is usually 8 to 12 inches for vegetables so roots have room. Set the depth field above to your bed's interior height rather than a thin topdressing figure. For a 4-by-8-foot bed filled 10 inches deep, that's about 27 cubic feet, or one cubic yard. Many gardeners blend topsoil with compost, so treat the topsoil figure as the soil portion of the mix, not the whole fill.
Related calculators
Sources
- How Much Does a Cubic Yard Weigh? — Topsoil, Sand, GravelThe Calculator SitePublished weight range for topsoil (about 2,000 to 2,700 lb per cubic yard) used to set the working figure of roughly 1.08 tons per cubic yard for dry soil.
- Soil Moisture and Bulk DensityOklahoma State University ExtensionUniversity reference on how moisture and composition change soil bulk density, explaining why delivered weight varies.