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Soil Calculator

Topsoil, fill dirt, garden soil or compost — for lawns, garden beds and raised beds.

Updated 2026-10-20 · Based on: supplier bulk densities (gravel ≈ 1.4 tons per yd³).

How to use the Soil Calculator

  1. Pick an area (rectangle or circle) or Raised bed.
  2. Enter the size and depth — 4–6 in for lawns, 12 in for raised beds.
  3. Choose the soil type and bag size.
  4. Read yards (bulk) or bags.

Formula

Cubic yards = length × width × depth (ft) ÷ 27.

Bags = volume ÷ bag size (1, 1.5 or 2 ft³). Topsoil weighs about 1.1 tons per yd³.

Worked example

With the values preset in the calculator above: (Rectangle)

Length
20 ft
Width
10 ft
Depth
4 in
Material
Topsoil
Bag size
1.5 ft³ bags
Extra for waste
5 %
Soil needed
2.59 yd³ (70 ft³)
Bags
47
Weight
2.84 tons (5,681 lb)
Estimated cost
$90.74

How much soil for a raised bed?

An 8 × 4 ft bed 12 in deep holds 32 ft³ — 1.19 yd³ (32 ft³), or 22 bags of 1.5 ft³. Mix about 60 % topsoil, 30 % compost and 10 % perlite or grit.

Soil for raised beds

Bed length (ft)Bed width (ft)Bed height (in)Soil neededBags (1.5 ft³ bags)
44120.59 yd³11
84121.19 yd³22
84181.78 yd³32
104242.96 yd³54

Frequently asked questions

How much topsoil do I need for a lawn?

Spread 4–6 in for a new lawn. 1,000 ft² at 4 in needs about 12.3 yd³.

How many bags of soil in a yard?

27 bags of 1 ft³, 18 of 1.5 ft³ or 13.5 of 2 ft³.

What is fill dirt used for?

Filling holes and raising grade under slabs or lawns. It has little organic matter, so top it with 4 in of topsoil for plants.

More calculators

All construction calculators →

Estimates only — check quantities with your supplier and local building code before you order.