Topsoil Calculator

Use this topsoil calculator to find how many cubic yards or bags of topsoil a lawn, garden or raised bed needs. Enter the size and depth of each area, and it gives you the volume to order, with extra for settling. It also does two things most soil calculators don’t: it splits a blend into topsoil, compost and sand so you can buy each part, and it compares the cost of bulk delivery with the cost of bags for your job.

About the topsoil calculator

Working out a volume of soil is quick. The decisions around it take longer. How deep should it go? Should a raised bed be straight topsoil or a mix? Is it worth paying for delivery, or should you load bags into the car? This tool is built around those questions.

• Several areas in one order. Up to 20 rows, each with its own shape and depth. A lawn topdressing at half an inch and two garden beds at 6 inches go in the same estimate.
• A mix, split into parts. Choose the 40 / 40 / 20 raised bed mix or enter your own percentages. You get cubic yards, cubic feet and bags for each ingredient.
• Bulk against bags. Enter a bulk price, a delivery fee, a bag size and a bag price. You see both totals and which is lower.
• Extra for settling. Loose soil packs down. The calculator adds 10% unless you change it.
• Weight. A range in tons for the topsoil, for deciding whether your trailer can take it.

It runs in your browser. Nothing you enter is sent anywhere or saved.

How to use the topsoil calculator

1. Choose your units. Feet with depth in inches, or metres with depth in centimetres.
2. Enter the first area. Pick the shape and type the measurements and the depth of soil you want.
3. Add more areas for each separate bed or lawn section. Use “How many” for identical beds.
4. Choose what goes in. Topsoil only, the raised bed mix, or your own mix.
5. Set the extra for settling. 10% is the starting figure.
6. Add prices if you want a comparison. A bulk price per cubic yard, a delivery fee, a bag size and a price per bag.

The topsoil calculator formula

Cubic yards = square feet x depth in inches / 324

A cubic yard is 27 cubic feet, and a foot is 12 inches, so 27 x 12 = 324. For a rectangle, square feet is length times width. For a circle it’s 3.1416 times half the diameter, squared. Then:

• To order = cubic yards x (1 + settling %)
• Each part of a mix = cubic yards to order x its percentage
• Bags = cubic feet / bag size, rounded up
• Bulk cost = cubic yards x price per yard + delivery

Topsoil calculator example: a new lawn area

You’re preparing a 20 ft by 10 ft patch for seed and want 4 inches of topsoil.

1. Area: 20 x 10 = 200 square feet.
2. In place: 200 x 4 / 324 = 2.47 cubic yards.
3. With 10% for settling: 2.72 cubic yards, which is 73.3 cubic feet.
4. Weight: about 2.17 to 3.53 tons.

A whole new lawn of 1,000 square feet at the same depth needs 12.35 cubic yards in place, or 13.58 with 10% extra.

Example: three raised beds with a mix

Three beds of 4 ft by 8 ft, filled 12 inches deep, hold 96 cubic feet: 3.56 cubic yards. With 10% extra you need 3.91 cubic yards. You choose the raised bed mix of 40% topsoil, 40% compost and 20% sand.

Notice the bag total. The whole volume divided by 1.5 would round to 71 bags. But you buy each ingredient separately, and each one rounds up by itself, so the real count is 73. The calculator adds them the way you’d buy them.

Example: topdressing a lawn and filling two beds

You want to topdress 800 square feet of lawn with half an inch of topsoil, and fill two 12 ft by 4 ft beds 6 inches deep.

A single-area calculator would need two runs and a pencil. Here both go in one order.

Bulk or bags: which is cheaper?

It depends on the size of the job and the delivery fee. These two examples use the same made-up prices: $40 a cubic yard in bulk, $75 for delivery, and $3 for a 0.75 cubic foot bag. Put your own local prices into the topsoil calculator to get your answer.

The pattern is general even though the prices aren’t. A delivery fee is a fixed cost, so it hurts small orders and barely matters on large ones. Bags cost more per cubic foot, but there’s no delivery fee and no pile on the driveway. Somewhere around a cubic yard or two, bulk usually takes over.

Cost isn’t the only factor. Bulk soil arrives as one heap that you move by wheelbarrow. Bags can be carried to exactly where they’re needed, and leftovers keep. If access is tight, or the job is spread around the garden, bags can be worth a premium.

Reading your result

• Cubic yards. The figure for a bulk supplier. It includes your settling allowance, and for a mix it’s the whole blend.
• Cubic feet. The figure to use against bag labels.
• Topsoil weight. A range in US tons for the topsoil in the order. Useful if you’re hauling it yourself.
• Bags. Appears when you choose a bag size. Rounded up, and for a mix rounded up per ingredient.
• Bulk cost and bag cost. Each appears when you enter its price. With both, the topsoil calculator names the cheaper option and the difference.
• The mix. For a blend, one line per ingredient with its cubic yards, cubic feet and bags.
• Area by area. One line per row, so a typing slip stands out.

Open “Show the working” to see each step written out.

Working in metres

Switch the units and the topsoil calculator takes lengths in metres and depth in centimetres. A 6 m by 3 m area covered 10 cm deep is 1.8 cubic metres, which is 2.35 cubic yards. Whatever you’d already typed is converted for you. Prices and bag sizes stay per cubic yard and per cubic foot, so if your supplier sells by the cubic metre, divide their price by 1.308 to get a price per cubic yard.

How deep should topsoil be?

These depths are from The Old Farmer’s Almanac.

Go deeper if the ground underneath is rocky or badly compacted. And measure what’s already there: topping up a bed that has 3 inches of good soil to 6 inches takes a 3-inch layer, not 6.

Topsoil coverage chart

The rule is 324 divided by the depth in inches. Halve the depth and the same soil covers twice the area.

Bags of topsoil per cubic yard

Bagged soil is labelled by volume, by weight, or both. If your bags only show a weight, look for the cubic feet in the small print, because the volume a 40 lb bag holds changes with how damp the soil is.

Topsoil, compost and sand: choosing a mix

• Topsoil is the mineral base. It gives a bed its bulk and holds water and nutrients.
• Compost adds organic matter, which feeds plants and improves structure. It keeps breaking down, so beds filled with a lot of it sink over the seasons.
• Sand opens up heavy soil so water drains through.

For raised beds, The Old Farmer’s Almanac suggests 40% topsoil, 40% compost and 20% sand. That’s the preset in the calculator. Recipes vary with climate, native soil and what you’re growing, so choose “My own mix” if a local nursery or extension service recommends something else. The three percentages have to add up to 100.

For lawns, straight topsoil is the usual choice. Many suppliers sell a ready-blended “garden mix” as well. If you’re buying one of those, leave the calculator on “Topsoil only” and order the total.

How much topsoil weighs

Loose, dry topsoil is listed at 1,600 lb per cubic yard in Caterpillar’s material density table and 1,620 lb in the Federal Highway Administration’s earthwork guidance. Soil that’s damp or less fluffy is heavier. Inch Calculator puts dry, loose soil at up to 1.3 tons a yard, which is 2,600 lb. The calculator shows the range between the two: 0.8 to 1.3 US tons per cubic yard.

That matters if you’re collecting it yourself. Two cubic yards could weigh 1.6 tons or 2.6 tons, and the second figure is beyond many pickup trucks and small trailers. Check your vehicle’s payload, and ask the yard what their soil weighs that day. After rain it will be toward the top.

The weight shown is for the topsoil part of your order only. We don’t show a weight for compost, because we couldn’t find a figure reliable enough to publish.

Why add extra for settling?

Soil is delivered loose and full of air. Once it’s spread, watered and walked on, it packs down. An order that exactly matches the measured volume ends up a little low. Calculator Soup suggests a settling and waste allowance of 10% to 20%. This tool starts at 10%, which suits most lawn and bed jobs. Use more for deep fills, and for mixes with a lot of compost.

Buying topsoil: what to look for

• Screened or unscreened. Screened topsoil has been sieved to remove stones, roots and clods. It spreads evenly and suits lawns and beds. Unscreened is cheaper and fine for filling low spots that will be covered.
• Look and feel. Good topsoil is dark and crumbly. It shouldn’t be sticky clay, pure sand, or full of debris.
• See it first if you can. “Topsoil” isn’t a regulated term in most places. Quality varies between suppliers and between loads.
• Ask about minimums. Many yards have a minimum delivery, and some sell by the half yard only.

Common mistakes

1. Leaving depth in inches. 20 x 10 x 4 is not 800 cubic feet. Four inches is a third of a foot. The calculator takes inches so you don’t convert.
2. Ordering the exact measured volume. It settles. Add the allowance.
3. Forgetting the delivery fee. A low price per yard can still lose to bags on a small job.
4. Counting bags from the total for a mix. Each ingredient rounds up separately.
5. Using the radius as the diameter. The circle shape wants the full width across.
6. Ignoring what’s already in the bed. Measure the gap you need to fill, not the full height.

What the topsoil calculator can’t tell you

• What your soil needs. A soil test tells you about pH and nutrients. Volume doesn’t.
• The right mix for your plants. The preset is one published recipe, not the only good one.
• Your supplier’s prices or soil weight. Both vary by area and by season.
• Uneven ground. The depth is treated as uniform. For a slope or a dip, use the average depth.

More project calculators

Raising or lowering the ground itself? The dirt calculator handles fill dirt and the soil you dig out. For gravel paths and river rock borders, the rock calculator gives tons. For mulch on top of the new bed, or concrete for the edging, use the cubic yard calculator. Building a retaining wall for a raised garden? The concrete block calculator counts the blocks. And the job estimate calculator turns your quantities into a quote.

Sources

• The Old Farmer’s Almanac, topsoil calculator page: depths by job and the 40 / 40 / 20 raised bed mix.
• Caterpillar, “Material Density Tables to Help Estimate Earthwork Volumes”: loose topsoil, 1,600 lb per cubic yard.
• Federal Highway Administration, Project Development and Design Manual, Earthwork Design, Exhibit 5.1-A: loose topsoil, 1,620 lb per cubic yard.
• Inch Calculator, soil calculator: dry, loose soil 1.0 to 1.3 tons per cubic yard.
• Calculator Soup, topsoil calculator: settling and waste allowance of 10% to 20%.
• All read on October 3 to 5, 2026. One cubic yard is 27 cubic feet.