Excavation & Spoil Calculator
Size the removed material first: compare bank volume to loose spoil, then decide how much can stay on site and how much still needs hauling.
Use this page for a fast bridge number or sanity check, then continue into the related calculators or guides below when the decision needs more than a raw conversion.
Choose finished footprint when you still need to add working room around the dig. Choose excavated footprint when the dimensions already describe the area being removed.
Related Tools
French Drain Calculator
Switch to the trench-material workflow when the excavation is really a drainage run.
Calculate →Catch Basin & Downspout Calculator
Move into basin, adapter, pipe, and outlet takeoff when the excavation is tied to roof or inlet capture.
Calculate →Fill Dirt Calculator
Estimate fill or grade-reset material if the site needs balancing after the cut.
Calculate →What This Utility Owns
This page is intentionally narrow. It owns the removed material only: the excavation footprint, the bank volume in place, the loose spoil after swell, and the basic reuse-vs-haul plan.
It does not estimate replacement base, gravel, topsoil, bedding sand, or concrete. Those remain in the dedicated material calculators so the numbers do not contradict each other.
Worked Example
Suppose a finished patio is 12 ft by 16 ft, the total dig depth is 7 inches, and you expect 25% swell. If you add 6 inches of working room around the dig, the excavated footprint becomes roughly 13 ft by 17 ft.
Bank volume = excavated footprint × depth
Loose spoil = bank volume × (1 + swell %)
That is why finished footprint and excavated footprint cannot be treated as the same thing. A compact patio or trench can turn into much more hauling once edge room and swell are added.
Frequently Asked Questions
What is the difference between bank volume and loose spoil?
Bank volume is the soil still in the ground before you dig. Loose spoil is the expanded volume after excavation. This tool shows both because hauling and disposal usually follow the loose volume, not the in-place bank volume.
When should I use finished footprint instead of excavated footprint?
Use finished footprint when you know the final patio, trench, or pad size but still need to add working room around the dig. Use excavated footprint when the measurements already describe the full area being removed.
Does this calculator estimate replacement gravel, base, soil, or concrete?
No. This page only owns removed material: excavation volume, loose spoil, keep-vs-haul framing, and simple hauling counts. Replacement layers still belong in the dedicated material calculators.