Fill Dirt Calculator

Free fill dirt calculator. Instant cubic yards plus tons at 2,000 lb/yd³, with the right compaction factor built in for accurate ordering. Free, no sign-up.

Fill dirt is the subsoil used to build grade, fill holes, and raise low spots in a yard. Unlike topsoil, it has very little organic matter — which is exactly what you want when you're trying to build up ground rather than grow things in it. A cubic yard of fill dirt weighs about 2,000 lb (1 US ton).

The big difference from topsoil: fill dirt compacts hard. The 25% compaction factor in the calculator is the right starting point for any project that will see load (driveway sub-base, building pad, retaining wall backfill). For light landscaping, you can drop the compaction to ×1.10.

When to use fill dirt

• Building up grade before laying sod or topsoil. A 4–6 inch layer of fill dirt, compacted, then 4–6 inches of topsoil on top is the standard recipe for a yard that needs raising.
• Filling holes left by pool removals, old septic tanks, or stump grinding.
• Retaining wall backfill. Compacted fill dirt behind a wall provides the drainage and the mass that keeps the wall from bowing out.
• Driveway sub-base. Before gravel goes down, fill dirt can level out a wavy subgrade.

Where fill dirt is not the right choice

• Don't plant directly in fill dirt. It has no nutrients and the heavy compaction will suffocate roots. Topsoil or a topsoil/compost blend on top.
• Don't use fill dirt in a vegetable garden. Heavy metals and old building debris are common in cheap fill.

How is fill dirt sold?

Most fill dirt comes from excavation sites — it's the subsoil that's removed when a basement is dug or a foundation is poured. Reputable suppliers screen it to remove rocks, roots, and debris. Ask your supplier where the dirt is from and whether it's been screened; clean fill is worth a small premium over the cheapest option.

Frequently asked questions