This topsoil calculator converts the size of your garden bed or lawn and a chosen depth into the soil volume you actually need, reported in cubic feet, cubic yards, and bags. It also estimates weight, which matters because suppliers often sell loose topsoil by the ton. Homeowners refreshing lawns, landscapers leveling beds, and contractors backfilling around hardscape all use it before ordering.
Working the numbers first prevents the two classic mistakes: ordering a mountain of soil you cannot use, or paying for a second small delivery.
The Formula Plus a Worked Example
The method is straightforward: multiply area by depth in feet, then divide by 27 to express the result in cubic yards. Topsoil usually runs 1.2 to 1.4 tons per cubic yard, depending on moisture and texture.
Picture a bed measuring 200 sq ft that needs 4 inches of new soil. Four inches equals 0.33 feet, so 200 x 0.33 is about 66.7 cubic feet. Divide by 27 to get 2.47 cubic yards, which weighs roughly 3.2 tons at 1.3 tons per yard.
How to Use It and Order Smart
Flip between the Imperial (in, ft, yd) and Metric (cm, m, kg) unit settings, enter your area and depth, then choose In Bags for small beds or In Bulk for loose delivery and press Calculate Topsoil. The results list topsoil needed, weight, and number of bags.
Convert inches to feet by dividing by 12 whenever you do the math manually. Order 5 to 10 percent extra so settling, uneven ground, and spillage never leave a patch bare, and remember loose soil compacts after the first heavy rain.
Frequently Asked Questions
How deep should topsoil be for grass?
Plan on 4 to 6 inches of quality topsoil when starting a new lawn from scratch. For overseeding or leveling an existing yard, a 2 to 4 inch layer is usually plenty.
How much does a yard of topsoil weigh?
A cubic yard of typical moist topsoil weighs about 1.2 to 1.4 tons. Drier sandy soil sits near the low end while wet clay can exceed it.
How many 40 pound bags make one yard?
One cubic yard equals 27 cubic feet, so roughly 36 bags at 0.75 cubic feet each. Bulk delivery costs far less for anything beyond a few yards.
Can I mix compost into topsoil?
Yes, blending 1 part compost with 3 parts topsoil builds fertility without going overboard. Pure compost can burn roots and still settles too quickly on its own.
When is the best time to spread topsoil?
Spring and early fall work best because soil is workable and moisture is moderate. Avoid spreading on frozen or saturated ground, since compaction ruins the structure.