How Much Topsoil Do I Need?

The amount of topsoil you need depends on your area and intended depth. Lawn top-dressing needs just 1–2 inches; raised beds from scratch need 8–12 inches.

The quick formula

Volume (cu yd) = Length (ft) × Width (ft) × Depth (in) ÷ 324

40 lb bags = Volume (cu ft) ÷ 0.75, rounded up

Depth guide by project type

Project	Recommended depth
Lawn top-dressing	1–2 inches
Overseeding prep	2–3 inches
New lawn / sod base	4–6 inches
Garden beds (existing)	3–4 inches
New garden beds	6–8 inches
Raised beds (from scratch)	8–12 inches

Coverage table — cubic yards needed per 100 sq ft

Depth	Cu yd needed	40 lb bags
1”	0.31	11
2”	0.62	22
4”	1.23	45
6”	1.85	67
8”	2.47	89
12”	3.70	133

Quick examples

Project	Size	Depth	Cu Yd	40 lb bags
Lawn patch	10 × 20 ft	2”	1.23	45
Garden bed	4 × 8 ft	6”	0.59	22
Raised bed	4 × 8 ft	12”	1.19	43

How to measure

Measure length and width of your bed or lawn area in feet.
Decide on depth using the table above for your project type.
Subtract obstacles — tree trunks, existing large plants, pathways.
Add 5% overage to account for settling and uneven ground.

For irregular shapes or multiple beds, use the Topsoil Calculator with the Irregular shape option.

Frequently Asked Questions

How many cubic yards of topsoil do I need for a 10×10 garden bed at 6 inches deep?

A 10×10 ft bed (100 sq ft) at 6 inches deep needs 1.85 cubic yards. That is about 67 bags of 40 lb topsoil, or roughly 2 tons of bulk topsoil.

How many 40-lb bags of topsoil equal a cubic yard?

It takes 36 bags of 40 lb topsoil to fill one cubic yard, since each bag yields about 0.75 cubic feet and there are 27 cubic feet in a cubic yard (27 ÷ 0.75 = 36).

How much does a yard of topsoil weigh?

Topsoil typically weighs around 2,200 lbs (1.1 tons) per cubic yard. Weight varies with moisture content — wet topsoil can weigh significantly more.

How deep should I add topsoil for a lawn?

For lawn top-dressing, 1–2 inches is enough. For new sod or seeding, 4–6 inches of good topsoil promotes strong root development. For raised beds, 8–12 inches.

When should I order bulk topsoil vs. bags?

Order bulk delivery for projects over 1.5–2 cubic yards — it is much cheaper per yard. Use bags for small patches, tight-access areas, or when you only need a fraction of a yard.