Fill Dirt Calculator

How Do I Calculate How Much Fill Dirt I Need?

Multiply length × width × depth (in feet), divide by 27 for cubic yards, then multiply by density for tons. Common fill weighs about 1.35 tons per cubic yard. A 20×10-foot area at 6 inches deep needs roughly 3.5 cubic yards or 4.7 tons. Add 15% for compacted applications.

Fill dirt is sold by the cubic yard for bulk delivery or by the ton depending on the supplier. To estimate quantity, multiply your project dimensions (in feet) by the depth (converted from inches), divide by 27 to get cubic yards, then multiply by the density of your fill type to get tons. Always add a waste factor — 5% for loose grading work, 15% or more for compacted applications.

Formula:Length (ft) × Width (ft) × Depth (in) ÷ 12 ÷ 27 = Cubic Yards. Multiply by density (tons per cubic yard) to get tons.

What Are the Different Types of Fill Dirt?

Clean fill (1.50 tons/yd³) is the workhorse for general grading; structural fill (1.55 tons/yd³) is engineered for load-bearing applications; common fill (1.35 tons/yd³) is cheapest for cosmetic grading. Clay fill is best for water barriers and pond liners. Sandy fill drains well for utility trenches.

Not all fill dirt is the same. Composition and density affect both how much you need and how it performs under load:

• Clean Fill (1.50 tons/yd³): Screened soil with no rocks, roots, or organic debris. The workhorse for general site grading and rough backfill.
• Common Fill (1.35 tons/yd³): Unscreened yard dirt. Cheapest option, fine for landscape grading and fills where compaction and appearance don't matter.
• Structural Fill (1.55 tons/yd³): Engineered sand-gravel blend with controlled gradation. Used beneath load-bearing slabs, building pads, and utility trenches where settlement must be minimized.
• Clay Fill (1.60 tons/yd³): Dense, impermeable soil. Best for pond liners, berms, and areas where you want water to pool rather than drain through.
• Sandy Fill (1.40 tons/yd³): Free-draining fill for utility trenches, pipe bedding, and areas where drainage matters more than compaction.

How Much Does Fill Dirt Shrink When Compacted?

Fill dirt loses 10–15% of its loose volume when compacted; clay fill can lose up to 20%. For compacted applications (building pads, sub-slab bases), order 15% more than your loose-yardage calculation. The calculator’s default 5% covers delivery spillage only.

Fill dirt shrinks when compacted. Loose-delivered fill typically loses 10–15% of its volume under standard compaction (plate compactor or jumping jack), while clay-heavy fill can lose up to 20%. For any fill that will be compacted in lifts — building pads, sub-slab bases, retaining wall backfill — order 15% more than your loose-yardage calculation shows.

The calculator's default 5% waste factor covers delivery spillage, grading losses, and cleanup, not compaction shrinkage. Bump the waste slider to at least 15% for compacted applications.

How Much Fill Dirt Fits in a Dump Truck?

A tandem-axle dump truck carries 10–14 cubic yards (14–20 tons) of fill dirt per load. A tri-axle carries 16–20 cubic yards. For small jobs under 5 yards, suppliers offer pickup by the half-yard scoop or smaller delivery trucks.

When Should I Use Structural Fill vs. Common Fill?

Use structural fill under anything that bears a load — building pads, concrete slabs, retaining wall bases, and utility trenches. Use common fill for cosmetic grading, raising low spots in a yard, or bulking up berms where compaction and load-bearing capacity don't matter.

Use structural fill whenever the fill will bear a load: building pads, under concrete slabs, beneath retaining wall bases, or anywhere future settlement would cause cracking or failure. Structural fill is engineered for predictable compaction and should always be placed in controlled lifts, with density testing on larger projects.

Use common fill for cosmetic or low-stakes grading: raising a low spot in a yard, bulking up a berm, or backfilling a temporary trench. It costs significantly less but cannot support structural loads without extensive reworking.

Cost varies by region. The Estimated Material Cost card pulls from our indicative national-average pricing dataset(refreshed quarterly). Northeast and California metros run 15–40% above the national midpoint while Midwest and Southeast metros run 5–15% below — verify locally for binding quotes.

How Much Does Bulk Fill Dirt Cost?

Clean fill from a nearby excavation is often free or near-free; structural fill runs $20–40 per cubic yard delivered. Always ask what the fill is sourced from and avoid material with construction debris or contaminated soil.

Fill dirt prices vary enormously by source and distance. Clean fill from a nearby excavation site is often free or very cheap — contractors pay to dispose of it, so they'll sometimes deliver for diesel cost only. Structural fill, by contrast, is an engineered product that typically runs $20–40 per cubic yard delivered.

Always ask what the fill is sourced from. Avoid material that may contain construction debris, contaminated soil, or excessive organic matter. For any fill going under a house, slab, or bearing structure, request a sieve analysis or soil test from the supplier and confirm the material meets your project's specified gradation before ordering.

Can I Use Fill Dirt to Grade Near a Foundation?

Yes — proper grading uses clean fill or sandy fill sloped away from the foundation at a minimum 6-inch fall over the first 10 feet (about 5%). Avoid clay fill near foundations because it expands when wet and can push against walls. Compact in 4-inch lifts with a plate compactor.

How Much Fill Dirt for a Foundation Backfill?

A 30×40-foot foundation with 4-foot-deep walls and 2 feet of backfill on all sides needs roughly 30–40 cubic yards (45–60 tons) of clean or structural fill. Compact in 4-inch lifts and slope the final grade away from the wall at 5%. Don’t backfill until the foundation has cured at least 7 days.

What's the Difference Between Fill Dirt and Topsoil?

Fill dirt is subsoil — the layer beneath topsoil — used for grading and structural backfill. It contains few nutrients and won't grow plants well. Topsoil is the upper organic-rich layer suitable for lawns and gardens. Use fill dirt to bring grade up; cap with 4–6 inches of topsoil where you want grass or planting beds.

How Do I Check if Fill Dirt Is Contaminated?

Ask the supplier for the source — clean fill should come from residential excavation or virgin earth, not industrial sites. Visually inspect for construction debris, oil staining, or unusual smells. For fill going under a house or vegetable garden, pay for a soil test ($50–150) checking for lead, petroleum, and pH before placement.

How Much Does Bulk fill dirt Cost?

Bulk fill dirt averages about $9.50 per ton nationally as of our April 2026 research. Common fill $5-15/cu yd; clean fill $10-25/cu yd. Regional variation is significant — Northeast and California metros run 15–40% above the national midpoint while Midwest and Southeast metros run 5–15% below. See our pricing methodology for sources and confidence tiers.

How Many Cubic Yards Is 1 Ton of Fill Dirt?

1 ton of common fill dirt equals about 0.74 cubic yards; 1 cubic yard equals about 1.35 tons. Density varies by fill type — common (unscreened) fill runs around 1.35 tons/yd³, clean (screened) fill 1.45 tons/yd³, and engineered structural fill 1.55 tons/yd³ or higher. The denser the fill, the fewer cubic yards per ton.

Tonnage above is loose-volume. Compacted fill loses 10–15% of its loose volume — order 15% extra over your calculated figure if you're placing fill under a slab or building pad.

Related Calculators

• Gravel Calculator— Estimate gravel for sub-bases and driveways
• Drainage Rock Calculator— Size French drains and footing drains
• Concrete Calculator— Estimate cubic yards for slabs over fill

Written by Daniel McCarney — AceCalc