How Much Crushed Stone Do I Need? Tons, Yards, and Coverage

A 12-by-24-foot patio at 4 inches deep needs about 3.56 cubic yards of crushed stone, or roughly 4.6 tons of #57 stone. That number comes from three inputs: area, depth, and the density of the stone you pick. The crushed stone calculator runs this math for you, but understanding how the pieces fit together helps you order the right amount and avoid a short delivery.

How Crushed Stone Volume Works

Every crushed stone estimate starts with volume. You need the area of your project and the depth of stone you plan to lay.

Volume (cubic feet) = Area (sq ft) x Depth (ft)

Cubic yards = Volume (cubic feet) / 27

Depth must be in feet before you multiply. Four inches is 0.333 feet, not 4 feet. That conversion trips up more orders than any other step in the process.

One cubic yard equals 27 cubic feet. Most suppliers sell in cubic yards for bulk delivery and by the ton for smaller quantities. Either way, the volume calculation is the foundation.

Converting Cubic Yards to Tons

Crushed stone is sold by weight as often as by volume. Converting between the two requires the stone’s density, measured in tons per cubic yard.

Common crushed stone densities:

Stone Type	Density (tons per cubic yard)
#57 stone (3/4 inch)	1.3
#411 stone (3/4 inch with fines)	1.35
#2 stone (2-3 inch)	1.25
Crushed limestone	1.5
Crusher run (mixed fines)	1.6

To get tons from cubic yards:

Tons = Cubic yards x Density (tons per cubic yard)

If you need 3 cubic yards of #57 stone: 3 x 1.3 = 3.9 tons. The same 3 cubic yards of crusher run: 3 x 1.6 = 4.8 tons. Same volume, different weight, same area covered. The density only changes your invoice and your truck’s payload. It does not change how much ground the stone covers.

Calculating by Project Shape

Rectangle

Most driveways, patios, and walkways are rectangular. Multiply length by width for area, then multiply by depth in feet.

A driveway 18 feet wide by 36 feet long at 6 inches deep:

• Area: 18 x 36 = 648 sq ft
• Volume: 648 x 0.5 = 324 cubic feet
• Cubic yards: 324 / 27 = 12 cubic yards

Circle

Fire pit surrounds, tree rings, and round patio pads use the circle formula.

Area = pi x radius x radius

A 10-foot-diameter circle (5-foot radius) at 3 inches deep:

• Area: 3.14 x 5 x 5 = 78.5 sq ft
• Volume: 78.5 x 0.25 = 19.6 cubic feet
• Cubic yards: 19.6 / 27 = 0.73 cubic yards

Irregular Areas

Most yards are not perfectly shaped. An L-shaped patio or a curved garden border does not fit a single formula.

Break the area into rectangles and circles that approximate the shape. Calculate each section separately and add the results. A 10-by-20 rectangle joined to a 6-by-12 extension is just two rectangles: (200 + 72) = 272 square feet total. Multiply by your depth from there.

The crushed stone calculator handles rectangle, circle, and direct area entry, so you can run each section and combine them.

Choosing the Right Depth

Depth varies by what the stone needs to support. Using driveway depth for a garden bed wastes material. Using garden bed depth for a driveway leads to ruts and exposed subgrade within a season.

Decorative beds and tree rings: 2 to 3 inches. Light foot traffic only.

Walkways and garden paths: 3 to 4 inches. Enough to stay firm under regular walking.

Patio base layer: 4 to 6 inches of compactable stone under pavers or flagstone. This is structural, not decorative.

Driveway surface: 4 to 6 inches. For gravel driveways, this goes on top of the base.

Driveway base: 6 to 8 inches of crusher run or #2 stone, compacted in lifts. This is the layer that prevents sinking and rutting.

Getting the depth wrong is the most expensive mistake you can make. Doubling depth from 3 inches to 6 inches doubles your material order. A 500-square-foot area at 3 inches needs 4.63 cubic yards. The same area at 6 inches needs 9.26 cubic yards. At #57 stone density, that extra 4.63 yards adds about 6 tons to your order and a second delivery truck to your driveway.

Aggregate Size and When It Matters

Crushed stone comes in graded sizes. The size you pick affects how the stone performs, not how much you need volume-wise.

#57 stone (3/4 inch): The most common size for driveways, drainage, and general fill. Angular pieces lock together well after compaction.

#2 stone (2-3 inch): Used for drainage trenches, French drains, and base layers where water needs to flow freely through the stone.

#411 stone (3/4 inch with fines): Has dust mixed in that fills gaps and compacts into a harder surface. Good for paths and parking pads where you want a firmer finish.

Crusher run (variable): A blend of crushed stone and fine dust. Compacts into a dense, stable base. The go-to choice for driveway sub-base and under concrete slabs.

Size does not change the volume formula. A cubic yard of #57 stone covers the same area at the same depth as a cubic yard of #2 stone. But size affects density, so the tonnage changes. And size affects how much the material compacts after installation. If you are working with natural landscape stone rather than crushed aggregate, the stone calculator covers a wider range of stone types and densities.

Waste Factor and Compaction

Order exactly what the math says and you will come up short. Every crushed stone project loses material to three things:

Spillage and edge loss. Stone spreads beyond your borders during installation. Wheelbarrow runs drop material. Raking pushes stone past the edge. Budget 5% for this on contained areas (between edging or walls) and 10% on open areas.

Subgrade irregularity. No ground is perfectly flat. Low spots absorb more stone than your depth calculation assumes. If you measured depth in one spot and the grade dips two inches elsewhere, that section takes significantly more material. Measure depth at three or four points and average them.

Compaction. Loose crushed stone settles 10 to 15% after compaction. Crusher run compacts even more because the fines fill voids as you run a plate compactor over it. A 6-inch layer of crusher run may settle to 5 inches after compaction.

For most projects, add 10% to your calculated volume. For driveway bases that will be mechanically compacted, add 15%.

Adjusted volume = Calculated cubic yards x 1.10 (or 1.15 for compacted bases)

The calculator includes a waste factor input. Set it to 10% for standard jobs and 15% for compacted bases so the output reflects what you actually need to order.

Driveway Example: Full Calculation

You are building a gravel driveway 16 feet wide by 40 feet long. It needs a 6-inch crusher run base and a 3-inch #57 stone surface.

Base layer (crusher run at 6 inches):

• Area: 16 x 40 = 640 sq ft
• Volume: 640 x 0.5 = 320 cubic feet = 11.85 cubic yards
• Add 15% for compaction: 11.85 x 1.15 = 13.63 cubic yards
• Tons: 13.63 x 1.6 = 21.8 tons of crusher run

Surface layer (#57 stone at 3 inches):

• Area: 640 sq ft
• Volume: 640 x 0.25 = 160 cubic feet = 5.93 cubic yards
• Add 10% for waste: 5.93 x 1.10 = 6.52 cubic yards
• Tons: 6.52 x 1.3 = 8.5 tons of #57 stone

Total order: 13.63 yards of crusher run + 6.52 yards of #57 stone. That is 21.8 tons + 8.5 tons = 30.3 tons across two deliveries.

Run each layer through the calculator separately. Mixing them into one calculation blends the depths and densities, giving you an inaccurate number.

Patio Base Example

A 12-by-16 patio base under flagstone at 4 inches of #57 stone:

• Area: 192 sq ft
• Volume: 192 x 0.333 = 64 cubic feet = 2.37 cubic yards
• Add 10% waste: 2.37 x 1.10 = 2.61 cubic yards
• Tons: 2.61 x 1.3 = 3.4 tons

Most stone yards have a minimum delivery of 3 to 5 tons. At 3.4 tons you are just above the typical minimum, so a single delivery covers it.

When Volume and Weight Quotes Disagree

Suppliers sometimes quote by volume and sometimes by weight. If you get quotes in both units, the density is what reconciles them.

A supplier quoting 5 tons of #57 stone is selling you 5 / 1.3 = 3.85 cubic yards. If your calculation says you need 4 cubic yards, that 5-ton quote is slightly short. Always convert back to the unit your math uses before comparing.

For a deeper look at how this volume-to-weight relationship plays out across different stone types, Stone Coverage Explained breaks down the connection between density, tonnage, and square footage.

The Quick Version

Measure your area. Pick the right depth for your project type. Multiply area by depth in feet for cubic feet, divide by 27 for cubic yards, multiply by density for tons. Add 10% for standard waste or 15% for compacted bases.

If you want a full walkthrough of measuring your site and working through the math by hand first, How Much Stone Do I Need? covers the step-by-step process. Or plug your numbers directly into the crushed stone calculator, pick your stone type, and it returns cubic feet, cubic yards, and tons in one step.