Fill Dirt Calculator
Estimate how much fill dirt you need to raise grade, backfill, or level a low spot — in cubic yards, tons, and bags, with the density and formula shown.
You need · incl. +10% extra
- Cubic feet
- 55 ft³
- Cubic meters
- 1.56 m³
- Pounds
- 5,093 lb
- Kilograms
- 2,310 kg
- Area
- 100 ft²
- Exact volume
- 1.85 yd³
- Density
- 1.25 t/yd³
- Bag size
- 0.5 ft³ bag
Order about 10–15% extra — fill compacts substantially, so the loose cubic yards you buy shrink once the dirt is placed and tamped. Settlement is larger over soft ground.
Raising grade or backfilling: place and compact in 6–8 in lifts. For load-bearing areas use structural fill compacted in thin lifts.
The formula & constants
Volume = Area × Depth. Convert to cubic yards (1 yd³ = 27 ft³), then Tons = Cubic yards × Density (fill dirt ≈ 1.25 tons/yd³).
| Fill Dirt density (working value) | 1.25 tons/yd³ |
| Typical range | 1.1–1.4 tons/yd³ |
| Cubic-yard conversion | 1 yd³ = 27 ft³ |
| Recommended overage | +10% |
Fill Dirt subtypes & their densities
| Subtype | Density |
|---|---|
| Fill dirt (subsoil) | 1.25 tons/yd³ |
| Structural / engineered fill | 1.4 tons/yd³ |
| Clean fill | 1.2 tons/yd³ |
| Sandy fill | 1.3 tons/yd³ |
Source: Typical fill dirt bulk density (~1.1–1.4 tons/yd³), per Omni Calculator. Densities vary with moisture and compaction — the weight figure is an estimate.
How much fill dirt do you need?
Fill dirt is the subsoil from below the topsoil layer — screened of organic matter so it does not decompose and settle later. That stability is the point: you use fill to raise grade, backfill against foundations and walls, level a low yard, or build up a pad. Because it holds its shape, it goes in compacted in lifts, not dumped loose.
Keep fill and topsoil in their lanes. Fill dirt is cheap structural material with no nutrients — wrong for growing anything. Build the area up with fill, compact it, then cap it with a 4–6 inch layer of topsoil if you plan to plant. For anything load-bearing (a slab pad, under a driveway), use structural or engineered fill and compact it in thin lifts so it does not settle under the load.
Fill is sold by the cubic yard and is one of the cheapest materials by volume, but it compacts a lot — expect the loose delivered yardage to shrink noticeably once tamped. Order 10–15% over the calculated volume, more over soft or wet ground where the fill works into the subgrade.
Frequently asked questions
How much fill dirt do I need?+
Multiply your area (length × width in feet) by your depth in feet for cubic feet, then divide by 27 for cubic yards. Enter your dimensions and depth above and the calculator shows cubic yards, tons, and bags live.
How much does a yard of fill dirt weigh?+
About 2,200–2,800 lb (roughly 1.1–1.4 US tons) per cubic yard, depending on its makeup and moisture. Wet or clay-heavy fill weighs more; sandy fill less.
What is the difference between fill dirt and topsoil?+
Fill dirt is the subsoil used to raise grade or backfill — stable, cheap, and inert. Topsoil is the nutrient-rich upper layer used for growing. Build up with fill, then cap with topsoil where you want to plant.
How deep can I place fill dirt at once?+
Place and compact fill in 6–8 inch lifts rather than one thick layer — a deep loose lift never compacts properly and settles unevenly later. Load-bearing areas need thinner lifts and more thorough compaction.
How much fill dirt to raise my yard?+
Measure the area in square feet and decide how many inches you want to raise it, then read the cubic yards. Raising a 500 sq ft area by 6 inches takes about 9–10 cubic yards before allowing for compaction.
Does fill dirt compact a lot?+
Yes — significantly. The loose cubic yards delivered shrink once the fill is placed and tamped, which is why you order 10–15% extra and build up in compacted lifts rather than expecting the loose volume to hold.
What is structural fill?+
Structural (engineered) fill is select material — often sandy or gravelly soil — placed and compacted in thin lifts to a specified density so it can safely carry loads, such as under a slab or driveway. Ordinary fill dirt is not rated for that.
How many bags of dirt are in a cubic yard?+
A cubic yard is 27 cubic feet, so it equals 54 of the common 0.5 ft³ bags. For anything beyond a tiny job, bulk delivery is far cheaper than bagged dirt.
Should I order extra fill dirt?+
Yes — add 10–15% because fill compacts and some works into the subgrade. Soft or wet ground needs the higher end.
Is this fill dirt calculator free?+
Yes — free, no sign-up, and it runs entirely in your browser, so nothing you enter is stored or sent anywhere.