Excavation Calculator

Estimate dig volume for a trench or foundation in cubic yards (both in-place (bank) and loose after swell) with the number of truck loads to haul it. Calculates in your browser.

25% is a starting value; swell depends on the soil type and moisture. Use your contractor’s or hauler’s figure if you have one.

Soil to haul (loose)

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In-place (bank) volume-
Truck loads-

Show the math

Bank volume is the dig; loose volume adds the swell:

bank = length × width × depth ÷ 27

loose = bank × (1 + swell%); loads = ⌈loose ÷ truck⌉

Excavated soil takes up more room once it is loosened; how much depends on the soil, so the 25% default is only a starting value. Add extra width for working room and shoring as the job requires. All math runs locally in your browser.

What this does

An excavation calculator estimates dig volume for a trench or foundation in cubic yards (both in-place (bank) and loose after swell) with truck loads to haul it.

How to use it

  1. Enter the length, width, and depth.
  2. Set the soil swell.
  3. Set the truck capacity.
  4. Read bank volume, loose volume, and loads.

How it works

Excavated soil takes up more room once loosened; the swell depends on the soil, so the 25% default is a starting value to replace with your contractor’s figure. Loose volume is what you haul; divide by truck capacity for loads.

loose volume = bank volume × (1 + swell)

Understanding your result

Two volumes matter for different reasons: the bank figure is what you dig, while the larger loose figure, swollen as soil is broken up, is what you actually haul away. Add room for working space and over-dig beyond the bare dimensions, and always have utilities located before you break ground, since hitting a line is dangerous and costly.

Example

A 20×3×4 ft trench is about 8.9 bank cubic yards.

Last updated .

Frequently asked questions

What is soil swell?

Excavated soil expands as it is loosened, by an amount that depends on the soil type and moisture. Bank volume is in-place; loose volume is what you actually haul away. The tool starts at 25%; use your contractor’s figure if you have one.

How many truck loads will I need?

Divide the loose volume by the truck capacity and round up. Ask your hauler for their truck’s capacity; the tool starts at 10 cubic yards.

Does it account for over-dig?

No, it uses your entered dimensions. Add extra width for working room and shoring as the job requires.

Do you store my numbers?

No. Everything is calculated locally in your browser.