Materials Calculators

Fill Dirt Calculator

Fill dirt is bulk subsoil for raising grade, backfilling, and leveling. Enter the area and depth for the cubic yards — and, using its density, the tons — to order.

How deep you're filling. For deep fills, build up and compact in lifts.

Fill dirt ≈ 1.0–1.4 ton/cu yd, but it swings widely with moisture and clay content — confirm with your supplier.

Fill dirt

3.7cu yd

Fill dirt
4.63 tons
Volume
100 cu ft

How it’s calculated

Volume = length × width × (depth ÷ 12) cubic feet, ÷ 27 for cubic yards. Tons = cubic yards × density. Fill dirt's density swings a lot with moisture and clay content (roughly 1.0–1.4 ton/cu yd), so it's an editable input — confirm your supplier's figure for an accurate ton order.

Worked example

A 20 × 10 ft area (200 sq ft) filled 6 in deep, at 1.25 ton/cu yd: 200 × 6 ÷ 12 = 100 cu ft = 3.70 cu yd × 1.25 ≈ 4.63 tons.

FAQs

What's the difference between fill dirt and topsoil?
Fill dirt is subsoil with little or no organic matter — used to raise grade, backfill, and build a stable base, because it compacts well and doesn't settle or decompose. Topsoil is the organic-rich top layer for growing. Don't plant in fill dirt, and don't use topsoil as structural fill.
Should I order extra for compaction?
Yes — fill is delivered loose but should be placed and compacted in lifts (a few inches at a time), and it loses volume as it's tamped and settles. Order extra (often ~20–30%, more for deep fills), and never dump a deep fill all at once or it will keep settling.
Why does the density vary so much?
Soil weight depends heavily on moisture and how much clay versus sand it contains — wet clay is far heavier than dry sandy fill. That's why we keep density as an input rather than guessing one number; use your supplier's figure if you're buying by the ton.

Sources

  • Volume = L × W × (depth ÷ 12) ÷ 27 (geometry). Tons = cu yd × density; density (~1.0–1.4 ton/cu yd, moisture/clay-dependent) is an editable, supplier-confirmed material property — not baked in.

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