Dirt Calculator - How Much Soil Do You Need?

Calculate exactly how much dirt or soil you need in cubic yards, cubic feet, or bags. Free calculator with weight estimates for landscaping and garden projects.

Nothing derails a weekend project faster than running out of dirt halfway through. You're covered in soil, the truck's gone, and now you're making an emergency run to the garden center for overpriced bags.

This calculator prevents that. Enter your measurements—length and width for rectangular areas, or total square footage for irregular spaces—and you'll know exactly how much soil to order. Results come in cubic yards (what suppliers quote), cubic feet, bag counts, and even weight estimates for both dry and wet conditions.

Whether you're filling raised beds, leveling a bumpy lawn, or hauling material in your truck, you'll have the numbers you need to order right the first time.

Quick Reference: How Much Does Dirt Cover?

Before diving into measurements, here's what a cubic yard actually gets you:

Cubic Yards

At 2" Deep

At 4" Deep

At 6" Deep

At 12" Deep

1

162 sq ft

81 sq ft

54 sq ft

27 sq ft

2

324 sq ft

162 sq ft

108 sq ft

54 sq ft

3

486 sq ft

243 sq ft

162 sq ft

81 sq ft

5

810 sq ft

405 sq ft

270 sq ft

135 sq ft

One cubic yard looks like a lot when it's piled in your driveway. It looks like almost nothing once you start spreading it.

How to Use This Calculator

Choose Your Measurement Style

The calculator offers two input options:

Option 1: Length, Width & Depth Best for rectangular spaces. Measure each dimension and enter them separately—you can mix units (feet for length, inches for depth) and the calculator converts automatically.

Option 2: Area & Depth Better for irregular shapes or when you've already calculated square footage. Just enter the total area and your fill depth.

Read Your Results

You'll get five outputs:

  • Cubic yards — The number to give your supplier
  • Cubic feet — Useful for comparing bag quantities
  • Bags needed — Based on standard 0.75 cu ft bags
  • Dry weight — For planning truck loads or trailer capacity
  • Wet weight — Because soil after rain weighs 30-40% more

The Math Behind It (So You Know It's Right)

The formula is straightforward:

Cubic Yards = (Length × Width × Depth in feet) ÷ 27

That "27" comes from there being 27 cubic feet in a cubic yard (3 × 3 × 3).

Worked Example:

You're building a 12 ft × 4 ft raised bed and want 10 inches of soil.

  1. Convert depth: 10 inches ÷ 12 = 0.833 feet
  2. Calculate volume: 12 × 4 × 0.833 = 40 cubic feet
  3. Convert to yards: 40 ÷ 27 = 1.48 cubic yards

Round up to 1.5 cubic yards—you'll use every bit.

How Deep Should You Go?

This is where most people get it wrong. They guess, order too little, and end up with thin coverage that doesn't perform.

Lawn Projects

Project

Depth

Why

Top dressing

1"

Just enough to fill low spots and add nutrients

Overseeding prep

2"

Creates seedbed without burying existing grass

New lawn from seed

4-6"

Roots need room; thin soil = thin lawn

Sod installation

4-5"

Sod roots need loose soil to establish

Garden Projects

Project

Depth

Why

Annual flower beds

4-6"

Adequate for shallow-rooted annuals

Perennial gardens

6-8"

Deeper roots need more room

Vegetable beds

10-12"

Root vegetables especially need depth

Raised beds on concrete/hardscape

12-18"

No existing soil beneath

The Settling Factor

Fresh soil compacts by about one-third as it settles. If you need 9 inches of finished depth, order enough for 12 inches. Skip this step and you'll be buying more in three months.

Soil Weight: Why It Matters More Than You Think

A pickup truck has a payload limit. A trailer has a weight rating. Your back has limits too. Soil is heavy—often heavier than people expect.

Weight Per Cubic Yard:

Soil Condition

Weight

Tons

Dry, screened topsoil

1,800-2,200 lbs

0.9-1.1

Average garden soil

2,000-2,600 lbs

1.0-1.3

Moist soil

2,400-2,900 lbs

1.2-1.45

Wet/saturated

2,800-3,400 lbs

1.4-1.7

Real-World Translation:

That 3 cubic yards you ordered for your raised beds? If it rained yesterday at the supply yard, you're looking at 8,400-10,200 pounds in your driveway. Most half-ton pickups max out around 1,500 pounds payload. Do the math before you try hauling it yourself.

The calculator shows both dry and wet weight ranges because what shows up depends on recent weather, how long it's been in the pile, and how it was stored.

Bags vs. Bulk: The Real Cost Comparison

Everyone asks this. Here's how to decide:

Bagged Soil

  • Typically $4-8 per 0.75-1 cubic foot bag
  • At $5 per bag, one cubic yard (27 cubic feet) costs $135-180
  • Advantages: No minimum order, easy to transport, store leftovers
  • Best for: Under 1 cubic yard, tight access areas, precise amounts

Bulk Delivery

  • Typically $25-50 per cubic yard plus delivery ($50-100)
  • Three cubic yards delivered might cost $125-250 total
  • Advantages: Much cheaper per yard, less packaging waste
  • Best for: Over 2 cubic yards, accessible delivery spot

The Breakeven Point

Around 1.5-2 cubic yards, bulk starts winning on price. But factor in convenience: if you can't get a dump truck to your backyard, bags might be worth the premium.

Pro Tips: What the Calculators Don't Tell You

Order on Monday or Tuesday

Landscape suppliers get slammed on weekends. Mid-week orders often get faster delivery and better service. Some offer weekday discounts.

Check the Source Material

Not all topsoil is equal. Ask what it's screened to (½" is standard for garden use) and whether it contains any compost. "Triple mix" (topsoil, compost, peat) costs more but performs better in gardens.

Measure Twice, Then Add 10%

Your measurements aren't perfect. The pile won't spread perfectly. Order 10% extra for regular projects, 15% for anything with compaction.

Mind the Weather

Wet soil is miserable to work with—heavy, sticky, and clumpy. If possible, schedule delivery during a dry spell and spread it before the next rain.

Know Your Truck's Limits

  • Half-ton pickup: ~0.5-0.75 cubic yards max (safely)
  • Three-quarter ton: ~1 cubic yard
  • Full-size with trailer: ~2-3 cubic yards

Overloading destroys suspensions and brakes. When in doubt, make two trips.

Project Examples: Real Numbers for Common Jobs

Example 1: Two 4×8 Raised Beds

Dimensions: 4 ft × 8 ft × 10" deep, quantity 2

Calculation:

  • Each bed: 4 × 8 × 0.833 = 26.7 cu ft
  • Both beds: 53.4 cu ft ÷ 27 = 1.98 cubic yards
  • With settling buffer: Order 2.5 cubic yards
  • Or approximately 71 bags (0.75 cu ft each)

Verdict: Borderline. Bulk delivery makes sense if available; otherwise, 36 two-cubic-foot bags works.

Example 2: Leveling a 20×30 Backyard

Area: 600 sq ft at 2" average depth

Calculation:

  • 600 × 0.167 = 100 cu ft
  • 100 ÷ 27 = 3.7 cubic yards
  • With overage: Order 4 cubic yards

Verdict: Definitely bulk delivery. That's 133+ bags otherwise.

Example 3: Top Dressing Front Lawn

Area: 2,000 sq ft at 0.5" depth

Calculation:

  • 2,000 × 0.042 = 84 cu ft
  • 84 ÷ 27 = 3.1 cubic yards

Verdict: Bulk delivery. At half-inch depth, coverage goes far but you're still moving over 3 tons of material.

Frequently Asked Questions

How do I measure an irregularly shaped area?

Break it into rough rectangles, calculate each, and add them up. For circles, measure the diameter and use: Area = π × radius². Or just measure at the widest and longest points and accept you'll have a bit extra—better than coming up short.

What's the difference between topsoil, fill dirt, and garden soil?

Topsoil is screened native soil—whatever was in the ground, minus rocks and debris. Fill dirt comes from deeper excavation—it's cheaper but has little organic matter and won't support plant growth well. Garden soil is topsoil mixed with compost, peat, or other amendments. Garden soil costs more but you won't need to amend it yourself. For filling large areas where plants aren't the priority, straight topsoil works fine.

The calculator says I need 2.3 cubic yards. What do I order?

Round up to 2.5 or even 3 yards. Suppliers can't deliver 0.3 of a yard, and you'll use the extra. Running short is always worse than having a small pile left over.

How accurate are the weight estimates?

Within about 15-20%. Soil composition varies—sandy soil is lighter, clay is heavier. Moisture makes the biggest difference. The ranges account for these variations so you can plan for worst-case scenarios.

Can I use this calculator for mulch, gravel, or sand?

Volume calculations work for any material. Weight estimates don't—they're calibrated for soil. Mulch weighs much less (400-800 lbs/yard), gravel weighs more (2,400-2,900 lbs/yard), sand sits around 2,500-3,000 lbs/yard.

Why do I need more soil than the calculator shows for finished depth?

Settling. Loose soil compacts 25-35% over the first few months as it's watered and gravity does its work. The calculator shows raw volume; add 30-35% for final depth requirements.

Is fill dirt the same as topsoil?

No. Fill dirt comes from deeper excavation—it's basically subsoil with minimal organic content. It's cheap and fine for filling holes or raising grade, but plants won't thrive in it. Use fill dirt for the bottom of deep projects, then cap with topsoil.

How many wheelbarrow trips per cubic yard?

About 9-14 trips with a standard wheelbarrow (2-3 cubic feet capacity). A full wheelbarrow of wet soil weighs 300-400 pounds, so pace yourself.

Should I till the soil into existing ground?

For gardens, yes—tilling the top 4-6 inches helps new soil integrate with existing soil and prevents a hard layer boundary that roots can't penetrate. For fill or leveling projects, tilling isn't necessary.

When's the best time to add soil?

Spring or fall when temperatures are moderate and rain is likely (but not excessive). Avoid adding soil during heat waves—it dries out fast and is brutal to spread. Avoid soggy conditions that create muddy, compacted messes.