How Much Topsoil Do I Need?
Quick answer: length × width × depth (in feet) ÷ 27 = cubic yards. A 2-inch top-dress over 1,000 sq ft of lawn needs about 6.2 cubic yards, or roughly 112 bags of 1.5 cu ft topsoil. Here's the full method.
- Topsoil volume formula
- Depth by use
- Cubic yards to bags
- Quick lookup: common areas
- Worked example
- Ordering tips
- FAQ
Topsoil volume formula
Topsoil is sold by the cubic yard (bulk) or by the bag (usually 1.5 cu ft). Work in feet: Length (ft) × Width (ft) × Depth (ft) ÷ 27 = cubic yards. Convert depth from inches first: 2 in = 0.167 ft, 3 in = 0.25 ft, 4 in = 0.333 ft.
Depth by use
| Use | Recommended depth |
|---|---|
| Lawn top-dress / leveling | 1/2–2 in |
| New grass over existing soil | 2–3 in |
| Garden / flower beds | 3–6 in |
| Deep raised beds | 6–12 in |
Cubic yards to bags
One cubic yard = 27 cubic feet. Topsoil bags are typically 1.5 cu ft, so you need about 18 bags per cubic yard. Bulk by the yard is usually cheaper for anything more than a few bags and is delivered by truck.
Quick lookup: common areas
| Area | Depth | Cubic yards | 1.5 cu ft bags |
|---|---|---|---|
| 10×10 garden bed | 4 in | 1.2 | ~22 |
| 500 sq ft lawn | 2 in | 3.1 | ~56 |
| 1,000 sq ft lawn | 2 in | 6.2 | ~112 |
| 2,000 sq ft lawn | 3 in | 18.5 | ~333 (order bulk) |
Worked example
- Lawn area = 40 × 25 = 1,000 sq ft
- Depth = 2 in = 0.167 ft
- Volume = 1,000 × 0.167 = 167 cu ft
- Cubic yards = 167 ÷ 27 = 6.2 cu yd
- 1.5 cu ft bags = 167 ÷ 1.5 = ~111 bags (or ~6 yards bulk)
Ordering tips
For anything over a couple of bags, order bulk topsoil by the yard — it's far cheaper per cubic foot and one delivery beats dozens of bags. Topsoil settles, so order a little extra to level off after watering. For a new lawn, put the soil down, rake it level, and water before seeding. Bulk topsoil is screened and free of large debris; it usually costs $15–$35 per yard delivered in 2026.
FAQ
Measure length × width × depth in feet and divide by 27 for cubic yards. A typical lawn topping of 2 inches over 1,000 sq ft needs about 6.2 cubic yards of topsoil.
About 2 inches for a lawn top-dress, 3–4 inches to establish new grass over poor soil, and 6+ inches for deep garden beds. Most plants root in the top 6–12 inches.
Topsoil bags are typically 1.5 cubic feet. There are 27 cu ft in a yard, so you need about 18 bags of 1.5 cu ft per cubic yard. Bulk by the yard is usually cheaper for big areas.
A thin top-dress of 1/2–1 inch over an existing lawn can level and improve it, but a thick layer smothers the grass. For a fresh lawn, remove old sod or till first before adding new topsoil.