Fill & Backfill Calculator — ft to yd³, tons, trucks, cost
How to use this calculator
Enter the in-place area you must fill and the compacted depth. The calculator returns the compacted (in-place) volume, the larger loose volume you actually order, hauled weight in tons, and dump-truck loads. Pick the shape that matches the job: a rectangle for grading and pads, a trench for pipe and utility backfill, or the gap around a foundation (outer excavation minus footing footprint).
Compaction / shrinkage factor — Loose delivered fill loses 15–25% of its volume once placed and compacted to ASTM D698 / D1557 density, so you must order the loose volume, not the in-place volume. Tons and truck loads are based on the loose quantity you actually buy and haul. Material densities (delivered loose): clean fill 2,400 lb/yd³, structural / bank-run fill 2,700, gravel / crushed stone 2,800, sand 2,600, clay 2,500, topsoil 2,100.
Saved Calculations
| Time | Shape | Material | Compact yd³ | Loose yd³ | Tons | Trucks | Cost |
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How to Calculate Fill and Backfill
Backfill is sold and hauled loose but specified compacted, so the order quantity is always larger than the hole. Measure the in-place area and the required compacted lift depth, choose the delivered material, then set the shrinkage factor for that soil and compaction effort. For utility trenches and footing backfill, allow over-dig for the OSHA-required side slope when you size the area — net cut/fill quantities can be checked against the cut and fill balance calculator, and the excavated hole itself with the excavation volume calculator.
Formulas
Compacted volume = L × W × depth ÷ 27 (ft³→yd³). Loose volume to order = compacted volume × (1 + shrinkage%). Hauled weight = loose volume × density (lb/yd³), tons = lbs ÷ 2,000. Truck loads = ⌈loose volume ÷ 14 yd³⌉. Foundation backfill area = outer L × W − foundation L × W, then × depth.
FAQ
Why order more than the hole? Loose fill loses 15–25% of its volume when compacted to a standard (ASTM D698) or modified (ASTM D1557) Proctor density. You buy and haul the loose volume, so weight and truck counts here are based on it.
How many yards per truck? A standard dump truck carries about 14 yd³; a tri-axle holds ~16–18 yd³ and a transfer truck up to 24 yd³. Heavy gravel may hit the legal weight limit before the box is full.
What about graded aggregate or topsoil specifically? For priced crushed-stone bases use the gravel & aggregate calculator; for planting depths and bagged amounts use the topsoil & mulch calculator. If the void is being filled with concrete instead of soil, size it with the concrete slab calculator.
Ordering tips
Delivered loose fill in the 2025 US runs roughly $15–28/ton for clean structural fill, $22–40/ton for #57 / 21A gravel, and $30–55/yd³ for screened topsoil — short-haul delivery often costs more than the dirt itself, so always price by the truckload (about $300–500 per 14 yd³ tandem in most markets). The single biggest estimator mistake on backfill is using the in-place volume instead of the loose-delivered volume: a 25% shrinkage means a 100 yd³ hole needs 125 yd³ on the ticket. For trench backfill, also remember OSHA 1926 Subpart P side-slope batter (1H:1V in Type C soil): the trench at grade is wider than the pipe zone, so cross-check with the excavation volume calculator before you order trucks.
