Excavation Calculator: Dirt to Remove & Haul
Find out how much soil you will dig and how much you will actually have to haul away once it swells. Works for rectangular pits, trenches and round holes.
A 10 × 12 ft excavation 3 feet deep removes 13.3 cubic yards of soil measured in the ground. Dug soil swells, so with a 25% swell you actually haul about 16.7 cubic yards, roughly two 10-yard truckloads. Formula: length × width × depth ÷ 27, then × (1 + swell).
Your numbers
Result
Bank volume and loose volume
Excavators and haulers talk about two volumes. Bank volume is the soil measured in the ground before digging. Loose volume is the same soil after it is dug and piled, which takes up more space because the soil is no longer compacted. You calculate the hole in bank volume and haul the loose volume.
loose cubic yards = bank cubic yards × (1 + swell)
Example: a 10 × 12 ft pit that is 3 ft deep is 360 cubic feet, or 13.3 cubic yards in the ground. At 25% swell you haul 16.7 cubic yards, which is two 10-yard truckloads.
Round holes
For a round excavation, volume is π × (diameter ÷ 2)² × depth. An 8 ft wide hole 3 ft deep is 150.8 cubic feet, about 5.6 cubic yards in the ground.
Bank volume for common excavations
| Size (L × W × D) | Bank yd³ | Loose yd³ at 25% swell |
|---|---|---|
| 10 × 10 × 2 ft | 7.4 | 9.3 |
| 10 × 12 × 3 ft | 13.3 | 16.7 |
| 12 × 12 × 4 ft | 21.3 | 26.7 |
| 20 × 10 × 3 ft | 22.2 | 27.8 |
| 30 × 15 × 4 ft | 66.7 | 83.3 |
Planning your haul
- If you keep the soil on site, you still need space to pile the loose volume.
- Backfill is the reverse problem: loose soil compacts back down, which is why fill needs a compaction allowance.
- Convert yards to weight with the yards to tons calculator. Wet clay can be too heavy to fill a truck by volume.
- For footings and trenches that will be filled with concrete, use the concrete calculator.
Before digging, call your local utility locating service so buried lines are marked, and check whether you need a permit for deep or large excavations.
Frequently asked questions
How do I calculate the cubic yards of an excavation?
Multiply length, width and depth in feet to get cubic feet, then divide by 27. A 10 × 12 ft pit 3 ft deep is 13.3 cubic yards in the ground.
What is swell in excavation?
Soil expands when it is dug because it is no longer compacted. A 25% swell means 1 cubic yard in the ground becomes about 1.25 cubic yards loose.
How many truckloads of dirt is that?
Divide the loose volume by the truck capacity and round up. 16.7 cubic yards in a 10-yard truck is two loads.
How deep is a typical footing trench?
It depends on frost depth and local code, so check with your building department rather than a generic number.
Do I need to call before I dig?
Yes. In the United States, 811 connects you to the utility locating service that marks buried lines before you dig.
Sources and further reading
- NIST Special Publication 811: conversion factors — National Institute of Standards and Technology
These references support the general guidance on this page. The calculator applies the standard formulas shown above to the numbers you enter.
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. Estimates only. Always confirm quantities with your supplier or a qualified contractor before ordering, and add extra for waste and site conditions.