Topsoil is the growing layer for lawns and gardens, and it is usually the largest single material purchase in a landscaping project by weight. This calculator converts the area and depth you need to cover into cubic yards for bulk delivery, tons for comparing quotes, and bag counts for small jobs — with an allowance for the settling that loose soil always does.
How to use the topsoil calculator
- Choose the area shape and enter its dimensions, or enter a known area.
- Enter the soil depth you want after the job is finished.
- Keep or adjust the extra for settling (15% by default).
- Check the density if you want an accurate weight; the default of 1.1 tons per cubic yard fits dry, screened topsoil.
- Pick a bag size to see the bagged equivalent, and optionally enter a bulk price to estimate cost.
Topsoil formulas
Worked example: a new lawn
A 25 × 20 ft lawn area (500 ft²) needs 4 inches of topsoil: 500 × 4 ÷ 12 = 166.7 ft³ (6.17 yd³).
Adding 15% for settling: 166.7 × 1.15 = 191.7 ft³ = 7.10 yd³.
At 1.1 tons per cubic yard that weighs about 7.8 tons. In 0.75 cu ft bags it would take 256 bags, while 7½ bulk yards at $35 a yard cost about $262.50 before delivery.
How deep should topsoil be?
| Project | Typical depth of topsoil |
|---|---|
| Top-dressing an existing lawn | ¼ – ½ in |
| Seeding or sodding a new lawn | 4 – 6 in |
| Flower and shrub beds | 8 – 12 in |
| Raised vegetable beds | 10 – 12 in or more |
| Leveling low spots | depth of the low spot, in thin layers |
Grass roots do most of their work in the top 4 to 6 inches, which is why new-lawn guidance focuses there. When top-dressing, spread no more than about half an inch at a time so the grass can grow through it.
Topsoil, garden soil and fill
Bulk suppliers usually sell several grades. Screened topsoil has been sifted to remove rocks and clods and is the usual choice for lawns. Garden soil or planting mix is topsoil blended with compost and is better for beds. Fill dirt is subsoil with little organic matter, used to build up grade beneath a topsoil layer. Mixing a few inches of new topsoil into the existing ground, rather than leaving a sharp boundary, helps water and roots move between the layers.
Buying tips
- Ask whether the supplier sells by the cubic yard or the ton, and whether weights are wet or dry. Rain-soaked soil can weigh 20% or more above its dry weight.
- Look at the soil before it is delivered, or ask for a sample. Good topsoil is dark, crumbly and free of construction debris and weed roots.
- A cooperative extension soil test (often inexpensive) shows whether the new soil needs lime or nutrients.
- For mulch on top of new beds, continue with the mulch calculator.
Frequently asked questions
How many cubic yards of topsoil do I need for a lawn?
Multiply the lawn area in square feet by the depth in inches and divide by 324. A 500 ft² lawn with 4 inches of new topsoil needs about 6.2 cubic yards, or about 7.1 yards once you add 15% for settling.
How much does a cubic yard of topsoil weigh?
Dry, screened topsoil typically weighs about 2,000 to 2,400 pounds per cubic yard — roughly a ton. Moist soil can weigh 2,700 pounds or more, so ask the supplier whether their weight is wet or dry.
How many bags of topsoil make a cubic yard?
A cubic yard is 27 cubic feet, so it takes 36 bags of 0.75 cu ft, 27 bags of 1 cu ft, 18 bags of 1.5 cu ft or 13.5 bags of 2 cu ft.
Why add extra for settling?
Soil delivered or bagged is loose. Once it is spread, watered and walked on, air pockets collapse and the layer gets thinner, commonly by 10 to 20 percent. Adding that allowance up front means you reach the finished depth you planned.
What is the difference between topsoil and fill dirt?
Topsoil is the upper layer of soil, rich in organic matter and suited to growing plants. Fill dirt comes from deeper layers, has little organic material and is used to raise grade or fill holes. Use fill for bulk and finish with topsoil where plants will grow.