Landscaping · updated 2026
Topsoil Calculator — Cubic Yards & Bags
Topsoil math decides whether your garden beds thrive or your new lawn struggles — too thin and roots hit hard subsoil, too thick and you bury the budget. This topsoil calculator converts your area and desired depth into cubic yards (for bulk delivery) plus 1-cu-ft bag counts (for store runs), with 2026 costs for both. Four inches is the standard for new beds; lawns being top-dressed need only 1–2 in.
3–4 in for new beds; 1–2 in for top-dressing a lawn; 6 in for vegetable gardens
Show the math
Volume = 20 × 20 × (4 ÷ 12) = 133.33 ft³
Cubic yards = 133.33 ÷ 27 = 4.94 yd³
1-cu-ft bags = 133.33 ÷ 1 = 134.0 (rounded up)
Bulk cost = 4.94 yd³ × $30–$50/yd³
Bag cost reference = 134.0 × $3–$5/bag
What the numbers mean
Volume is the footprint multiplied by the material depth. Cubic yards help compare supplier quotes; tons are the purchase unit for asphalt and gravel.
The asphalt calculator applies 145 lb per cubic foot. The gravel calculator applies 110 lb per cubic foot. Asphalt also adds the waste factor you select.
The material cost is a national planning range before delivery, labor, excavation, base preparation, tax, or other project-specific charges.
2026 material prices
| Material | 2026 average price | Note |
|---|---|---|
| Bulk screened topsoil, per cubic yard | $30.00 – $50.00 / cubic yard | Delivered; unscreened runs cheaper |
| Topsoil, 1-cu-ft bag | $3.00 – $5.00 / 1-cu-ft bag | Retail |
Material prices: Wave 1 Batch 1 2026 national-average guide, Sep 2026. Local prices vary. 2026 U.S. national averages. Prices vary by region and retailer — confirm locally before buying.
Pro tips
- Above about 1 cubic yard (27 bags), bulk delivery is dramatically cheaper — and skips 27 plastic bags.
- A cubic yard of topsoil weighs roughly a ton (2,000 lbs) — a pickup bed holds 1–2 yards max, so plan delivery for bigger jobs.
- Buy screened topsoil for beds and lawns; unscreened is fine for filling low spots you will cover later.
- Rough up the existing soil before spreading — topsoil layered over compacted clay drains poorly at the boundary.
- For vegetable gardens, go 6 in deep and mix in compost; straight topsoil alone is rarely fertile enough.
- A 20×20 bed at 4 in needs 4.9 yards — order 5 and you will have a little left for settling.
Common questions
Frequently asked questions
How much topsoil for a 20×20 garden at 4 inches deep?
20 × 20 × (4/12) = 133.3 cu ft = 4.9 cubic yards — or 134 one-cu-ft bags.
How many bags of topsoil in a cubic yard?
27 one-cu-ft bags per cubic yard.
Topsoil vs garden soil — what is the difference?
Topsoil is the base ingredient; bagged "garden soil" is topsoil blended with compost and amendments, better for planting but pricier.
How deep should topsoil be for a new lawn?
3–4 in under sod or seed; 1–2 in is enough for top-dressing an existing lawn.
Bulk or bagged topsoil?
Bulk wins above about 1 cubic yard; bags make sense for small beds and trunk-sized loads.
How much does a yard of topsoil weigh?
Roughly 2,000 lbs (one ton) — confirm your trailer and truck ratings before hauling it yourself.
Related calculators
Planning estimates only. Prices are 2026 U.S. national averages and vary by region — confirm with your local supplier before buying.