Fill & Backfill Calculator — ft to yd³, tons, trucks, cost
How to use this calculator
Calculate volume, weight, and number of truck loads for fill and backfill operations. Choose from three area shapes: rectangle, trench, or around a foundation. Select material type (each has preset density) and apply a compaction/shrinkage factor to determine how much loose material you need to order.
Compaction factor — Loose fill shrinks 15–25% when compacted. Order 15–25% extra to reach the required compacted volume.
Materials — Clean fill (2,400 lb/yd³), structural fill (2,700), gravel (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
This calculator estimates the volume and weight of fill material needed for backfilling excavations, grading, or landscape fill. Choose from rectangular areas, trenches, or the gap around a foundation. Material density accounts for clean fill, structural fill, gravel, sand, clay, and topsoil.
Formulas
Compacted volume = L × W × depth. Loose volume = compacted volume × (1 + shrinkage%). Weight = loose volume × density (lb/yd³). Truck loads = ⌈loose volume / 14 yd³⌉. Foundation backfill = (outer L × W − foundation L × W) × depth.
FAQ
Why order extra? Loose fill compacts by 15–25% when properly compacted per ASTM D698 (standard Proctor) or D1557 (modified Proctor). You must order loose volume, not compacted.
How many yards per truck? A standard dump truck carries about 14 yd³. Tri-axle holds ~16–18 yd³. Transfer trucks up to 24 yd³.
