Worked examples

Filling a low spot in the yard

An area 15 ft × 8 ft that is 6 inches low, with 15% extra for compaction.

2.56 yd³ · ≈ 3.32 US tons

Backfilling around a foundation

A trench 40 ft long, 2 ft wide and 3 ft deep, with 10% extra.

9.78 yd³ · ≈ 12.71 US tons

Dirt for a round fire pit mound

A circle 8 ft across and 1 ft high, no extra.

1.86 yd³ · ≈ 2.42 US tons

Good for

Backfilling after digging out roots, pools or old pads
Raising a low spot before you place topsoil or sod on top
Estimating how many yards a landscaper should deliver for rough grade
Comparing fill dirt vs sand when drainage is the real goal

Common mistakes

Using fill dirt as the only growing medium in a vegetable bed
Forgetting compaction — tamped fill needs more volume than loose piles suggest
Ordering topsoil prices for a job that only needs cheap fill below grade
Measuring the hole at the top only when sides slope inward

How to calculate how much dirt you need

Find the volume of the space. For a rectangle, multiply length × width × depth in feet. For a round hole, use π × (diameter ÷ 2)² × depth.
Convert depth to feet first (inches ÷ 12). Mixing inches and feet is the most common mistake.
Divide cubic feet by 27 to get cubic yards.
Add an allowance for compaction. Loose fill settles when tamped or rained on, so you need more than the hole’s measured volume.
To estimate tons, multiply by the dirt’s weight per cubic yard (fill dirt is typically around 1.2–1.5 tons).

Cubic yards for common raised bed sizes

Exact volume with no extra allowance.

Bed size	Fill depth	Cubic yards
4 ft × 4 ft	6 in	0.30
4 ft × 4 ft	12 in	0.59
4 ft × 8 ft	6 in	0.59
4 ft × 8 ft	12 in	1.19
4 ft × 12 ft	6 in	0.89
4 ft × 12 ft	12 in	1.78
3 ft × 6 ft	6 in	0.33
3 ft × 6 ft	12 in	0.67

Approximate weight per cubic yard

Typical values used by this calculator. Wet dirt weighs more.

Material	US tons per cubic yard (typical range)	Value used here
Topsoil	1.1 – 1.4	1.25
Fill dirt	1.2 – 1.5	1.3
Sand	1.2 – 1.5	1.35

Frequently asked questions

How many cubic yards of dirt do I need to fill a hole?

Measure length, width and depth in feet, multiply them, and divide by 27. Then add 10% or so for compaction. For a hole 5 ft × 4 ft × 3 ft that is 60 ÷ 27 = 2.2 cubic yards, or about 2.4 with 10% extra.

How much does a cubic yard of dirt weigh?

Often around 1.2 to 1.5 US tons, depending on moisture and how much clay, sand or rock is in it. This calculator uses a middle value for each type.

What is the difference between fill dirt and topsoil?

Fill dirt is subsoil used to raise or level ground and give a stable base. Topsoil is richer in organic matter and is meant for growing plants. Use fill for depth and finish with topsoil if you will plant.

How much dirt fits in a pickup truck?

It depends on the truck bed and the weight limit. Weight, not volume, is usually the limit for dirt, so check your truck’s payload rating against the tons shown above before loading.

Do I need extra dirt for compaction?

Usually yes. Loose fill packs down when it is tamped, watered or driven over. Contractors often add around 10% or more depending on the soil and how firmly it will be compacted. Ask your supplier or contractor for a figure that fits your job.

Sources and updates

Last reviewed 2026-10-14.

NIST – Unit conversion factors – Length definitions used for unit conversion.
Fill dirt density and compaction allowance – Typical supplier ranges. Replace with named sources before launch.

Estimates for planning. Compaction and weight vary by soil, so confirm with your supplier or contractor.

Dirt Calculator