Topsoil Calculator
This topsoil calculator shows how much topsoil you need, in cubic yards or cubic metres, for a lawn, flower bed, garden or raised beds. Enter the size and depth in feet and inches, and it adds an allowance, works out the weight, shows how far a yard will go, and compares bulk delivery with bagged soil. Tap the i button beside any field for an explanation.
Quick answer: topsoil in cubic yards = length (ft) × width (ft) × depth (in) ÷ 324. A 20 × 15 ft area at 4 in deep needs about 3.70 cubic yards, or 4.25 with a 10% allowance. One cubic yard covers 81 square feet at 4 inches.
Calculate how much topsoil you need
Example values are loaded so you can see a result straight away. Change any field and the numbers update.
1. Choose your units
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2. What are you covering?
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3. Extra allowance, weight and hauling
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4. Bulk delivery price (optional)
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5. Bagged topsoil (optional)
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Topsoil needed at different depths
Order size at different allowances
Bulk delivery or bags?
Estimates for planning only. Prices and weights shown are examples you can edit, not quotes. Confirm measurements on site and check the details with your supplier. See our Disclaimer.
How the topsoil calculator works
Topsoil is sold by volume, usually in cubic yards, and sometimes by weight. Whether you want to know how much topsoil you need for a new lawn, a flower bed or a set of raised beds, the question comes down to one number: the volume of the space you are filling, plus a little extra.
This online topsoil calculator handles four situations: a rectangle, a round bed, an area you have already measured in square feet, and raised beds. Give it the size and the depth, and it returns the volume in cubic yards (or cubic metres), the amount to order after rounding up, the weight, the area one yard will cover, and the cost as bulk delivery and as bags. Tap the i button beside any field for a plain-language explanation.
How to calculate how much topsoil you need
If you would rather check the answer by hand, or work it out on site, the method takes four steps:
- Measure the area in square feet. For a rectangle, multiply length by width. For an odd shape, split it into rectangles and add them, or use our square footage calculator.
- Convert the depth to feet. Divide the depth in inches by 12. Four inches is 0.333 feet.
- Multiply area by depth to get cubic feet, then divide by 27 to get cubic yards.
- Add an allowance for settling and uneven ground, and round up to the size your supplier delivers.
Worked example: a 20 × 15 ft lawn area, 4 in deep
The area is 20 × 15 = 300 square feet. At 4 inches deep, the volume is 300 × 0.333 = 100 cubic feet, which is 3.70 cubic yards. Adding 10% brings it to 4.07 cubic yards, and a supplier who delivers in quarter-yard steps would take the order as 4.25 cubic yards.
The 324 shortcut
When the depth is in inches, you can skip the conversions: length in feet × width in feet × depth in inches ÷ 324. The 324 comes from 27 × 12, the two conversions folded into one. The same lawn gives 20 × 15 × 4 ÷ 324 = 3.70. It is quick to key into a phone while you stand in the yard.
Round beds
For a circle, the area is 0.7854 × diameter × diameter. A round bed 12 ft across has an area of 113.1 square feet. At 6 inches deep it holds 2.09 cubic yards before any allowance.
How many cubic feet are in a yard of dirt?
A cubic yard is a cube 3 feet on each side, so it holds 3 × 3 × 3 = 27 cubic feet. When a supplier or a website talks about “a yard of dirt” or “a yard of topsoil,” this is the unit they mean, not a square yard and not a length. A cubic yard is also about 0.7646 cubic metres.
| Cubic yards | Cubic feet | Cubic metres |
|---|---|---|
| 0.25 | 6.75 | 0.19 |
| 0.5 | 13.5 | 0.38 |
| 1 | 27 | 0.76 |
| 2 | 54 | 1.53 |
| 5 | 135 | 3.82 |
| 10 | 270 | 7.65 |
If you have the volume in cubic feet, divide by 27 for yards. If you have a figure in cubic metres and want yards, multiply by 1.308. The conversion factors come from the National Institute of Standards and Technology, linked at the end of the page.
How much does a yard of topsoil cover?
This is the topsoil coverage calculation in reverse, and it is a handy way to sanity-check a quote. One cubic yard covers 324 divided by the depth in inches, in square feet. At 4 inches that is 81 square feet, and at 6 inches it is 54.
| Depth | Area covered by 1 cubic yard | Cubic yards for 1,000 sq ft |
|---|---|---|
| 1 in | 324 sq ft | 3.09 |
| 2 in | 162 sq ft | 6.17 |
| 3 in | 108 sq ft | 9.26 |
| 4 in | 81 sq ft | 12.35 |
| 6 in | 54 sq ft | 18.52 |
| 8 in | 40.5 sq ft | 24.69 |
| 12 in | 27 sq ft | 37.04 |
If someone tells you 2 yards will cover 400 square feet at 4 inches, the table shows that 400 square feet needs closer to 5 yards. Use the table to check any estimate before you place an order.
How deep should topsoil be?
The right depth depends on the job. These figures are quoted from university extension services, and each row names its source.
| Situation | Figure quoted | Source |
|---|---|---|
| New lawn on bare ground | At least 4 to 6 in of firmed or settled topsoil | Penn State Extension |
| Unframed raised bed | 8 to 12 in above the surrounding soil | Utah State University Extension |
| Framed raised bed for vegetables | Box at least 6 to 12 in high | Utah State University Extension |
| Bed over hardscape or compacted soil: leafy greens, beans, cucumber | At least 8 in deep | University of Maryland Extension |
| Bed over hardscape or compacted soil: peppers, tomatoes, squash | 12 to 24 in deep | University of Maryland Extension |
| Enclosed bed on a lawn | Compost and purchased topsoil in a 1:2 or 1:1 ratio | University of Maryland Extension |
For a new lawn, Penn State Extension describes the depth as firmed or settled, which matters because loose soil settles after it is watered. That is one reason to add an allowance on top of the depth you want. For levelling low spots or patching a thin area, use the depth of the hollow you are filling rather than a lawn-from-scratch figure.
When the topsoil goes over existing ground, some guidance suggests blending the layers instead of leaving a sharp line between them. Penn State suggests mixing about 2 inches of topsoil into the top 2 to 3 inches of subsoil.
How much topsoil for common projects?
These are the quantities for typical areas at 4 inches and 6 inches deep, with a 10% allowance and rounding up to the next quarter yard. They assume the area is flat and the depth is uniform.
| Area | Net at 4 in (yd³) | Order at 4 in (yd³) | Net at 6 in (yd³) | Order at 6 in (yd³) |
|---|---|---|---|---|
| 100 sq ft | 1.23 | 1.50 | 1.85 | 2.25 |
| 300 sq ft | 3.70 | 4.25 | 5.56 | 6.25 |
| 500 sq ft | 6.17 | 7.00 | 9.26 | 10.25 |
| 1,000 sq ft | 12.35 | 13.75 | 18.52 | 20.50 |
| 2,500 sq ft | 30.86 | 34.00 | 46.30 | 51.00 |
| 5,000 sq ft | 61.73 | 68.00 | 92.59 | 102.00 |
Treat the table as a starting point. Slopes and dips change the average depth, so measure at several points. For an area with several parts, such as a lawn plus a border, run each part separately and add the totals, or use the area mode and enter the combined square footage.
How much extra should you order?
Adding about 10% is a common allowance. Ground is never perfectly flat, spread soil settles, and some gets lost on the way from the pile to the bed. The calculator uses 10% as its default and lets you change it, because a carefully graded site needs less than a rough one.
Depth is the number that moves your order most. Volume rises in direct proportion to it, so an extra inch on a 4 inch layer adds 25% to the order. On the example lawn, going from 4 to 5 inches takes the order from 4.25 to 5.25 cubic yards. The first chart in the results shows how your own order changes with depth, and the second shows how it responds to the allowance.
How much soil for raised beds?
A raised bed is a simple box, so the volume is length × width × fill depth. Two beds that are 8 ft long, 4 ft wide and 12 inches deep hold 2 × 8 × 4 × 1 = 64 cubic feet, or 2.37 cubic yards. With 10% extra that becomes 2.61, and a quarter-yard order is 2.75 cubic yards.
Raised beds are rarely filled with topsoil alone, and the guidance varies with the situation. The University of Maryland Extension describes filling a bed on a lawn with compost and purchased topsoil in a 1:2 or 1:1 ratio. Utah State University Extension recommends amending native topsoil with 30 to 50% well-composted organic matter by volume. Enter the topsoil share in the bed mode of the calculator and it will separate the topsoil from the other material. At 60% topsoil, the same two beds need 1.42 cubic yards of topsoil and 0.95 cubic yards of compost or other fill.
The same Utah State publication suggests framed beds be at least 6 to 12 inches high for most vegetables, so the depth you build sets how much soil you buy.
| Bed size | Fill depth | Volume (cu ft) | Cubic yards | Bags of 1 cu ft (no extra) |
|---|---|---|---|---|
| 4 × 4 ft | 12 in | 16.0 | 0.59 | 16 |
| 3 × 6 ft | 12 in | 18.0 | 0.67 | 18 |
| 4 × 8 ft | 8 in | 21.3 | 0.79 | 22 |
| 4 × 8 ft | 12 in | 32.0 | 1.19 | 32 |
| 4 × 12 ft | 12 in | 48.0 | 1.78 | 48 |
| 4 × 8 ft | 18 in | 48.0 | 1.78 | 48 |
How much does a yard of topsoil weigh?
The weight of topsoil varies with moisture, organic content and how coarse the soil is. For that reason, the calculator treats the weight per cubic yard as an editable figure and starts at 2,200 pounds. If your supplier gives you a number, enter it instead.
The table below shows what a few weights per yard work out to in tons. It is arithmetic on the figure you choose, not a statement about any particular soil.
| Weight per cubic yard | Tons per cubic yard | Cubic yards per ton | Tons in 5 cubic yards |
|---|---|---|---|
| 2,000 lb | 1.00 | 1.00 | 5.0 |
| 2,200 lb | 1.10 | 0.91 | 5.5 |
| 2,400 lb | 1.20 | 0.83 | 6.0 |
| 2,700 lb | 1.35 | 0.74 | 6.8 |
Weight matters for two reasons. Some suppliers sell by the ton and not by the yard, and a vehicle has a payload limit. Check the payload rating on your vehicle’s door-jamb label before you haul a load yourself. The calculator turns your order into trips for the payload you enter.
Bagged topsoil or bulk delivery?
Bags suit small jobs, and bulk delivery is usually cheaper per yard once the job grows. The bag size is printed on the label in cubic feet or litres, so divide 27 by it to find the bags in a yard.
| Bag size | Roughly | Bags per cubic yard | Bags per cubic metre |
|---|---|---|---|
| 0.5 cu ft | 14 litres | 54 | 71 |
| 0.75 cu ft | 21 litres | 36 | 48 |
| 1 cu ft | 28 litres | 27 | 36 |
| 1.5 cu ft | 42 litres | 18 | 24 |
| 2 cu ft | 57 litres | 14 | 18 |
At the example prices in the calculator, a bag priced at $4 for 0.75 cubic feet works out to $144 per cubic yard. Bulk topsoil at $40 per yard plus a $75 delivery fee is cheaper once the order passes roughly 0.7 cubic yards. Your prices will differ, so enter your own to see where the line falls for your job.
What to ask a topsoil supplier
Two loads called “topsoil” can be quite different, so a few questions are worth asking before you order:
- Is it sold by the yard or by the ton? The calculator shows both so you can compare quotes on the same basis.
- Is it screened? Screened soil has had stones and large debris removed, which matters for a lawn that needs a smooth surface.
- What is in it? Ask whether it is natural topsoil, a blend with compost or sand, or fill dirt. Each suits a different job.
- What is the delivery fee and the minimum load? Small orders often carry a minimum charge.
- Where will the truck tip it? Tell them about gates, slopes, soft ground and overhead wires.
A soil test through your local extension service is the reliable way to learn the pH and nutrient levels of the soil you are about to spread.
Common mistakes when ordering topsoil
- Mixing units. Multiplying feet by inches gives a wrong answer. Convert the depth to feet first, or use the 324 shortcut.
- Using the loose depth. Measure the finished, settled depth you want, not the height of the pile.
- Forgetting the allowance. Settling and uneven ground eat into the order.
- Confusing yards of length with cubic yards. Suppliers normally mean volume.
- Ordering by volume and paying by weight. If your quote is per ton, convert the volume with a weight you trust.
This page is a planning tool and does not replace soil testing or advice for your site. For drainage problems, grade changes or retaining walls, speak to a qualified landscaper or engineer.
Topsoil calculator FAQ
How much topsoil do I need?
Multiply the area by the depth to get the volume, then divide by 27 to turn cubic feet into cubic yards. The shortcut is length in feet × width in feet × depth in inches ÷ 324. Add about 10% for settling and uneven ground, and round up to your supplier’s order size.
How do I calculate how much topsoil I need for a lawn?
Measure the area in square feet and decide on a finished depth. A 20 × 15 ft area at 4 inches is 3.70 cubic yards, or 4.07 with a 10% allowance. Penn State Extension describes a new lawn as needing at least 4 to 6 inches of firmed or settled topsoil.
How many square feet does a yard of topsoil cover?
Divide 324 by the depth in inches. A single cubic yard spreads over 162 square feet at 2 inches, 81 at 4 inches, 54 at 6 inches and 27 at 12 inches.
How many cubic feet are in a cubic yard of dirt?
There are 27. A cubic yard of dirt or topsoil is a cube 3 feet on each side, and 3 × 3 × 3 = 27. In metric terms it is about 0.765 cubic metres.
How much topsoil do I need for 1,000 square feet?
At 4 inches deep, 1,000 square feet needs 12.35 cubic yards. With a 10% allowance that is 13.58, which a supplier working in quarter yards would deliver as 13.75. At 6 inches the order is 20.50 cubic yards.
How much does a yard of topsoil weigh?
It depends on moisture, organic content and the mix, so use your supplier’s figure when you can. The calculator starts at 2,200 pounds per cubic yard as an editable example, which is 1.1 tons. Change it to match your quote.
How much soil do I need for a raised bed?
Multiply length × width × fill depth. A 4 × 8 ft bed filled 12 inches deep holds 32 cubic feet, or 1.19 cubic yards. If you blend topsoil with compost, enter the topsoil share in the calculator to see how much of each you need.
Is it cheaper to buy topsoil in bags or in bulk?
For anything beyond a small job, bulk is usually cheaper per cubic yard, but delivery fees and minimum loads change that for very small orders. At the example prices in the calculator, bags win only below roughly 0.7 cubic yards. Enter your own prices to compare.
How much topsoil is in a bag?
The bag size is printed on the label, usually in cubic feet or litres, and sizes vary by brand. Divide 27 by the size in cubic feet to find the bags in a cubic yard, for example 36 bags of 0.75 cubic feet.
Should I order extra topsoil?
Yes. Spread topsoil settles after watering, and the ground is rarely perfectly level, so about 10% extra is a common allowance. Running short can mean a second delivery fee and a load that does not match the first.
Sources and further reading
The volume formulas are plain geometry. The depth guidance comes from the university extension services below, while the weight and price figures in the calculator are editable examples. For the full guidance, go to the source:
- Penn State Extension, Lawn Establishment (topsoil depth for a new lawn)
- University of Maryland Extension, Filling Your Raised Bed (compost and topsoil ratios, bed depths)
- Utah State University Extension, Raised Bed Gardening (bed height and soil mix)
- NIST Special Publication 811, Guide for the Use of the International System of Units (unit conversion factors)
Local conditions and rules differ, so confirm the details with your supplier and your local extension office.
Plan the rest of the project
If the same project includes a patio, path or footing, the concrete yard calculator works out cubic yards for those pours, and the concrete slab cost calculator prices the slab. The concrete calculators hub lists the rest of our pouring and building tools.