Excavation Volume Calculator
Enter your dig dimensions to get the excavation volume in cubic yards — and how many truck loads that means.
Runs entirely in your browser — your numbers never leave this page.
How it works
Excavation math is volume math — with one twist: soil swells when you dig it up:
Bank yd³ = L × W × D ÷ 27 → Loose yd³ ≈ Bank × 1.25
- Bank yards = the hole's volume in place. Loose yards = what the pile measures (air between clods).
- Sloped trench: safe 1:1 side slopes widen the top by the depth on each side — average width = bottom width + depth.
- Truck loads: always divide loose yards by truck capacity, and round up.
- Backfill: compacted fill takes ~90% of bank volume — the rest is the footing/pipe now occupying the hole.
- Safety: trenches 5+ ft deep need a protective system (shoring, shielding, or sloping) — cave-ins kill. Call 811 first.
Frequently asked questions
How many cubic yards is my trench?
Length × width × depth in feet, divided by 27. A 60×3×4 ft trench = 720 ft³ = 26.7 bank yards.
What is swell factor?
Dug soil takes up ~20–30% more volume than in the ground. Multiply bank yards by 1.25 for loose yards when planning haul-off.
How many truck loads?
Loose cubic yards ÷ truck capacity, rounded up. 33 loose yards ÷ 10-yd truck = 4 loads.
How deep can I dig without shoring?
OSHA requires a protective system at 5 ft+. Under 5 ft, a competent person must still inspect for cave-in risk.
How much backfill do I need?
Roughly 90% of bank volume, compacted in lifts — the footing or pipe displaces the rest.
What does 811 do?
Call 811 (US) before digging — utilities mark buried lines free within a few days. Hitting a gas line is catastrophic.
Bank vs loose vs compacted yards?
Bank = in-place volume; loose = after digging (swelled); compacted = after tamping (densest). Haul in loose, buy fill in compacted.
How do sloped sides change volume?
With 1:1 slopes, the top width = bottom width + 2× depth. Volume per foot = depth × (bottom width + depth).
What does excavation cost per yard?
Varies wildly by region and access — $50–150/yd³ is a rough range for machine digging with haul-off. Get local quotes.
Can I reuse the dug soil?
Often yes for backfill if it's clean and compacts well — saves haul-off and import costs. Test for contamination on old sites.