Excavation Cost Calculator

How much does excavation cost?

An excavation cost calculator prices a dig in two parts: removing the soil and running the machine. Cubic yards = length × width × (depth in inches ÷ 12) ÷ 27. Total cost = cubic yards × haul-off price per yard + footprint area × machine labor per square foot. A 30 × 20 ft dig 18 inches deep removes 33.33 cubic yards and costs about $2,033 at $25 per yard and $2 per square foot.

Use it for garage and shed pads, patio sub-bases, pond and pool holes, and basement dig-outs. It is a budget check, not a bid. Soil type, access, and what lies underground change real prices a lot.

How the estimate works

1. Footprint = length × width, in square feet.
2. Cubic yards = footprint × (depth ÷ 12) ÷ 27. This is the hole’s in-place (bank) volume.
3. Haul-off cost = cubic yards × price per yard.
4. Machine cost = footprint × labor rate.
5. Total = haul-off + machine.

Worked examples

Garage pad prep: 30 × 20 ft, 18 in deep, $25/yd³, $2/sq ft

• Footprint: 600 sq ft
• Volume: 600 × 1.5 ÷ 27 = 33.33 yd³
• Haul-off: 33.33 × $25 = $833.33
• Machine: 600 × $2 = $1,200.00
• Total: $2,033.33

In-ground pool hole: 32 × 16 ft, 60 in average depth, same rates

• Footprint: 512 sq ft
• Volume: 512 × 5 ÷ 27 = 94.81 yd³
• Haul-off: $2,370.37. Machine: $1,024.00.
• Total: $3,394.37

The pool hole moves almost three times the soil of the garage pad, but machine labor is lower because it is charged by footprint. For deep digs, raise the labor rate. A basement or pool takes far more machine hours per square foot than a shallow pad.

Cost by dig size (defaults: $25/yd³, $2/sq ft)

Dig	Depth	Cubic yards (bank)	Loose yards at +25%	Total
15 × 10 ft	18 in	8.33	about 10.4	$508.33
24 × 24 ft	12 in	21.33	about 26.7	$1,685.33
100 ft trench, 2 ft wide	36 in	22.22	about 27.8	$955.56
30 × 20 ft	18 in	33.33	about 41.7	$2,033.33
60 × 40 ft	18 in	133.33	about 166.7	$8,133.33
40 × 30 ft basement	8 ft	355.56	about 444.4	$11,288.89

Loose yards are shown at a 25% swell for planning only. The calculator itself uses bank volume.

Swell: why you need more trucks than the hole suggests

Soil	Typical swell when dug
Sand and gravel	about 10–15%
Common earth / loam	about 20–30%
Clay	about 30–40%
Blasted rock	50% or more

These are rough ranges from earthwork practice. Ask your hauler how they charge: by bank yard, by loose yard, or by truckload.

How to measure the dig

• Measure the footprint at the bottom of the hole and add working room. Foundations usually need extra width for forms and drainage.
• For sloped sides, average the top and bottom widths.
• Use the full depth to the bottom of the cut, including the gravel base layer if it goes in the same hole.
• Long narrow cuts are easier with the trench volume calculator.

Common mistakes

• Booking trucks for bank volume. Use loose volume for truck or dumpster space.
• Hauling soil you will need back. Keep good fill for backfill around walls; size it with the backfill calculator.
• Skipping the locate. Hitting a gas or power line is dangerous and expensive. Call 811 every time.
• Forgetting grading. Spreading and shaping the leftover soil is a separate step; see the land grading cost calculator.

For foundation projects, pair this with the concrete foundation cost calculator. Deep excavations near footings or over about 5 ft need shoring or sloping under safety rules, so hire a licensed excavation contractor for anything beyond a shallow dig.