How Much Topsoil Do I Need? (2026 Guide)

How is topsoil sold?

Topsoil is sold loose by the cubic yard for bulk deliveries and bagged by the cubic foot for small jobs. A cubic yard is 27 cubic feet, and bulk loads are billed per whole yard — your order rounds up to the next full yard.

The topsoil math, step by step

We'll use a 500 sq ft garden bed at 4 in deep as the example.

1. Measure the bed in square feet

For a rectangle, multiply length by width: a 25×20 ft bed is 500 sq ft. For L-shapes, split the area into rectangles and triangles and add the pieces.

2. Convert the depth to feet

Volume math works in feet, so turn inches into feet: 4 in ÷ 12 = 0.333 ft.

3. Multiply for cubic feet, then divide by 27

Cubic feet = area × depth: 500 × 0.333 ≈ 167 cu ft. Cubic yards = cu ft ÷ 27: 167 ÷ 27 ≈ 6.2 cu yd.

Because delivery is billed per whole yard and loose soil settles as it compacts, round up: order 7 cu yd. Run the topsoil calculator to check any other size.

What a cubic yard covers

Each row is 27 cu ft spread at that depth:

Cross-check: 500 sq ft ÷ 81 sq ft per yard at 4 in ≈ 6.2 cu yd — same result as the step-by-step math.

Topsoil for common bed sizes

Estimates are rounded to the nearest tenth of a yard; bulk deliveries bill per whole yard, so round up when ordering:

Under about a yard, buy bagged topsoil instead: 1 cu yd = 27 cu ft, so bags = cu ft needed ÷ bag size. Above that, bulk delivery plus a settling allowance is cheaper.

Loose vs. settled — buy a little extra

Freshly delivered topsoil is loose and fluffy. After you spread it, water it, and it rains a few times, it settles 10–15% — a freshly graded 6 in bed can end up near 5 in. Order about 10% extra: the 6.2 cu yd job above becomes roughly 6.8 cu yd, which the 7 yd order already covers.

• Whole-yard billing — the step from 6.2 to 7 yd already builds in most of the settling allowance.
• Deep fills (6 in+) — more soil means more total compaction; use the full 10–15% cushion.
• Odd shapes — curved beds and slopes waste part of every load; round up to the next full yard.

How deep should topsoil be?

Match the depth to the job:

• New lawn or raised bed — 4–6 in of topsoil over the prepared subgrade gives grass and most vegetables room to grow.
• Refreshing an existing lawn — 1–2 in topdressing to level dips and add organic matter.
• Test your soil first — a simple test shows whether you need to adjust pH or add compost, so you don't buy topsoil for a problem it can't fix.

Final tips: spread it right

• Rake it level before you plant — spread in thin lifts and rake between each one so you don't bury the grade.
• Water it in stages — light watering between lifts settles each layer instead of leaving a void that collapses later.
• Measure twice, order once — double-check your square footage and depth before you commit to a delivery.

The same measure-then-estimate playbook works for mulch for a 10×10 garden and sod for a new lawn.

Calculate your exact topsoil →