Topsoil Calculator
Calculate exactly how many cubic yards, tons, or bags of topsoil you need for a new lawn, garden bed, or grading project.
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Topsoil Layer Depth
For healthy lawns and gardens, you need a nutrient-rich topsoil layer spread over your subsoil. Measure your yard area and select a depth (usually 4-6 inches for new lawns).
How to Use the Topsoil Calculator
Buying bags of dirt from the hardware store can get incredibly expensive. Our calculator tells you exactly how much soil you need so you can decide whether to buy bags or arrange a bulk delivery.
- Measure the area: Input the length and width of the lawn, garden bed, or raised planter.
- Determine depth: Enter how many inches of soil you want to add. (4-6 inches is standard for new lawns).
- View the results: The calculator outputs cubic yards for bulk deliveries and 40 lb bags for store runs.
Topsoil Calculator Formula
Topsoil is sold by volume, so finding the cubic yardage is the most important step.
Step 1: Calculate Square Footage
Area = Length (ft) × Width (ft)
Step 2: Calculate Cubic Feet
Volume (ft³) = Area × (Depth in inches ÷ 12)
Step 3: Convert to Yards
Cubic Yards = Cubic Feet ÷ 27
Step 4: Convert to Bags
Bags (40 lb) = (Cubic Feet × 75 lbs/ft³) ÷ 40 lbs
Topsoil Example Calculation
You want to build a raised garden bed that is 8 feet long, 4 feet wide, and 12 inches deep.
- Area: 8 × 4 = 32 square feet.
- Depth: 12 inches is exactly 1 foot.
- Volume: 32 × 1 = 32 cubic feet.
- Convert to yards: 32 ÷ 27 = 1.18 cubic yards.
Conclusion: You need slightly more than 1 cubic yard of topsoil to fill the raised bed.
Tips for Landscaping with Topsoil
- Buy screened topsoil: Bulk topsoil is sold "screened" or "unscreened." Screened soil has been passed through a mesh to remove large rocks, roots, and clumps. It costs slightly more but is absolutely necessary for lawns and gardens.
- Check your truck capacity: A standard half-ton pickup truck (like an F-150 or Silverado 1500) can typically haul a maximum of 1 cubic yard of dry topsoil in the bed safely. If the soil is wet, haul less to avoid overloading your suspension.
- Account for settling: Freshly poured topsoil is loose and full of air. Once it rains, it will settle and compact by about 10-15%. Keep this in mind if you are trying to match the level of a driveway or sidewalk.
Frequently Asked Questions
How many inches of topsoil do I need to plant grass?
If you are seeding a new lawn over poor quality subsoil, you should add a minimum of 4 to 6 inches of good quality screened topsoil.
How much does a cubic yard of topsoil weigh?
Dry topsoil weighs about 2,000 lbs (1 ton) per cubic yard. However, if the soil is wet, it can weigh significantly more—up to 1.3 tons per yard. This is important to know if you are hauling it in a pickup truck.
How many 40 lb bags of topsoil make a cubic yard?
It takes roughly 54 bags (at 40 lbs each) to equal one cubic yard of topsoil. Because of this, it is almost always much cheaper to buy bulk topsoil by the yard if your project requires more than a half yard.
What is the difference between topsoil and fill dirt?
Topsoil is the nutrient-rich, dark upper layer of soil that contains organic matter necessary for plant growth. Fill dirt is taken from deeper in the ground, lacks organic matter, and is used strictly for building up elevation or filling holes before topsoil is applied.