Excavation Calculator — Dirt Volume & Truck Loads
Estimate a dig or a fill. Enter the dimensions and this calculator gives you the in-ground cubic yards, the loose volume after swell (what you actually haul), the weight in tons, and the number of dump-truck loads.
How to use this calculator
- Enter the length, width, and depth of the area to excavate.
- Read the in-ground cubic yards for fill ordering, and the loose volume for hauling — dug soil expands about 25%.
- Choose your truck size to get the number of loads to haul away.
- Call 811 (US) to locate buried utilities before any digging.
The formula
Excavated soil swells once dug, so we report both in-ground and loose volumes.
In-ground (cubic yards) = length × width × depth (in) ÷ 12 ÷ 27.
Loose volume = in-ground × 1.25 (≈25% swell). Weight ≈ in-ground × 1.35 tons. Truck loads = loose volume ÷ truck capacity, rounded up.
Worked example
A 20 ft × 10 ft area dug 12 in deep, hauled by a 12 cu yd truck.
In-ground = 20 × 10 × (12 ÷ 12) ÷ 27 = 7.4 cu ydLoose = 7.4 × 1.25 = 9.3 cu ydLoads = 9.3 ÷ 12 = 0.77 → 1 load
This dig is about 7.4 cubic yards in ground, ~9.3 loose — one dump-truck load.
Frequently asked questions
Why is loose volume more than the hole?
Soil expands when excavated because digging breaks up its compacted structure and adds air. This "swell" is typically 15–30% for soil, so you haul more volume than the hole measures.
How much does a cubic yard of dirt weigh?
Roughly 1.3–1.5 tons per cubic yard for typical soil, heavier when wet or full of clay, lighter for loose topsoil. We use about 1.35 tons per cubic yard.
How many cubic yards does a dump truck hold?
A tandem-axle dump truck carries about 10–14 cubic yards; a single-axle truck around 8. Weight limits often matter more than volume for heavy, wet soil.