Dirt vs. Fill Dirt vs. Topsoil — Which Do You Need?

Before you order, make sure you're buying the right product. The wrong choice costs money and causes problems.

TypeWhat It IsBest ForCost per Yard
Fill dirtSubsoil, no organic matter, clay-heavyGrading, raising elevation, backfill$5 – $25
Clean fillScreened fill, no debris or contaminantsBuilding pads, structural fill$10 – $30
TopsoilNutrient-rich, organic surface soilLawns, gardens, planting$20 – $55
Garden soilTopsoil + compost blendGarden beds, containers$30 – $60

Key distinction: Fill dirt doesn't settle as much as topsoil because it has no organic material to decompose. That's why builders use it for foundations, grading, and retaining walls. Use topsoil only where you want things to grow.

Need topsoil instead? Check our topsoil calculator guide.

The Dirt Formula

Length (ft) × Width (ft) × Depth (ft) ÷ 27 = Cubic Yards

Or if your depth is in inches:

Square Feet × Depth (inches) ÷ 324 = Cubic Yards

Example: Filling a low area, 30 × 20 ft, 8 inches deep

  1. Area: 600 sq ft
  2. 600 × 8 ÷ 324 = 14.81 cubic yards
  3. Add 20% compaction factor: 14.81 × 1.20 = 17.78 yards
  4. Order: 18 cubic yards
Key Takeaway

Always add 10-20% extra for fill dirt. Unlike mulch or gravel, fill dirt is meant to be compacted — it shrinks when you pack it down. Without the extra, you'll end up short.

The Compaction Factor (Don't Skip This)

This is where most people miscalculate. Loose fill dirt compacts by 10-20% when you tamp or roll it. If you need 10 cubic yards of compacted dirt, you should order 12 cubic yards of loose dirt.

Soil TypeCompaction RateOrder Extra
Sandy fill10 – 15%Order 10-15% extra
Clay fill15 – 25%Order 20% extra
Mixed fill (sand + clay)10 – 20%Order 15% extra
Topsoil (organic)15 – 20%Order 15-20% extra
⚠️ Don't compact topsoil

Compaction is for fill dirt only. If you're building garden beds, you want the soil to stay loose so roots can grow. Only compact dirt that's being used for grading, foundations, or backfill.

Calculate Fill Dirt Instantly

Enter your dimensions and depth. The calculator includes the compaction factor.

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How Many Cubic Yards in a Dump Truck?

When you order dirt, it arrives by dump truck. Knowing the standard truck sizes helps you plan deliveries and figure out if you need one load or two.

Truck TypeCapacity (Cubic Yards)Weight Capacity
Pickup truck0.5 – 1 yd³1,500 – 2,000 lbs
Small dump truck5 – 6 yd³10,000 – 13,000 lbs
Standard dump truck10 – 12 yd³20,000 – 26,000 lbs
Tandem axle dump truck12 – 16 yd³26,000 – 34,000 lbs
Tri-axle dump truck16 – 18 yd³40,000+ lbs
Transfer dump trailer24 – 30 yd³50,000+ lbs

So if you need 18 cubic yards, a standard dump truck (10-12 yd³) would need two trips. A tandem axle truck could handle it in one load. Ask your supplier what size truck they use — it affects the delivery fee.

How Much Does Dirt Weigh Per Yard?

Weight matters for two reasons: delivery costs and whether your vehicle can handle it.

Dirt TypeLbs per Cubic YardTons per Cubic Yard
Loose fill dirt (dry)2,000 – 2,4001.0 – 1.2
Compacted fill dirt2,400 – 2,8001.2 – 1.4
Fill dirt (wet)2,600 – 3,2001.3 – 1.6
Topsoil (dry)1,800 – 2,2000.9 – 1.1
Clay soil2,500 – 3,0001.25 – 1.50

A quick rule of thumb: 1 cubic yard of dirt ≈ 1 ton. Wet or clay-heavy dirt can be closer to 1.3-1.5 tons per yard.

For precise weight conversions, use our cubic yards to tons calculator.

💡 Free fill dirt

Construction sites often give away fill dirt for free — you just pay for hauling. Check local classifieds, construction company bulletin boards, or apps like "Fill Dirt Free" in your area. The quality varies, so ask what's in it before accepting.

Excavation: Calculating Dirt Removal

Working in reverse — digging out dirt instead of filling — uses the same formula. But there's a catch: excavated dirt expands by about 20-30% because it's no longer compacted.

If you dig out 10 cubic yards of compacted earth, you'll have 12-13 cubic yards of loose dirt to haul away. Keep this in mind when ordering dumpsters or dump truck pickups.

Get Your Exact Number

Free Dirt Calculator

Enter dimensions and depth. Get cubic yards with compaction factor built in.

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