Results update as you type. Round up when ordering.
Based on 0.75 cu ft bags of topsoil, a common store size. Check the bag label.
Formula checked against manufacturer specs
Rounded up to whole units
Runs in your browser
Topsoil formula
Cubic yards = area × depth (in) ÷ 12 ÷ 27. Dry screened topsoil weighs roughly 1 to 1.3 tons per cubic yard; wet soil is heavier. Common retail bags are 0.75 or 1 cu ft.
Example: 500 sq ft at 4 in = 166.7 cu ft = 6.17 cu yd ≈ 6.8 tons at 1.1 t/yd. That's 223 bags of 0.75 cu ft—bulk delivery makes far more sense.
How deep?
Top-dressing an existing lawn: 1/4–1/2 in
New lawn over poor soil: 4–6 in
Vegetable beds: 8–12 in (often a topsoil/compost blend)
Topsoil settles; order about 10–20% extra for fills deeper than a few inches.
It uses the standard formula shown on this page and rounds bags, boxes and pieces up to whole units. Product sizes vary by brand, so confirm with the label or your supplier before you buy.
Should I buy extra material?
Yes. A 5–10% allowance covers cuts, spills and uneven surfaces; running short mid-job usually costs more than a few leftovers.
Is this calculator free?
Yes. Every PorchMath calculator is free, needs no account and runs entirely in your browser.