Crushed Stone Calculator

How it's calculated

The calculator first finds the volume of the area in cubic feet: length (ft) × width (ft) × depth (in ÷ 12). That's converted to cubic yards by dividing by 27, since a cubic yard is 3 ft × 3 ft × 3 ft. A waste percentage is added on top to cover spillage and an uneven sub-base, and the adjusted cubic yardage is multiplied by crushed stone's density (tons per cubic yard) to get the weight in tons. Bag counts divide the adjusted cubic feet by each bag's yield; truckloads divide the adjusted cubic yards by the truck's capacity.

Worked example

A 10 ft × 10 ft driveway base at 4 inches deep: volume = 10 × 10 × (4 ÷ 12) = 33.33 cubic feet. In cubic yards, that's 33.33 ÷ 27 = 1.23 yd³. Adding a 10% waste factor: 1.23 × 1.10 = 1.36 yd³. At 1.40 tons per cubic yard, that's 1.36 × 1.40 = 1.90 tons — or 1.83–1.97 tons across the full 1.35–1.45 density range, and higher still if the material is wet or compacted. In 0.5 cu ft bags, the adjusted 36.67 cu ft (33.33 × 1.10) would need 74 bags — past the point where bagged material makes sense, so this is a bulk order.

How deep should it be?

Depth for crushed stone depends heavily on what job the layer is doing, and unlike gravel, the stone's angularity means it locks together and compacts differently. A 2" layer works for a drainage bed or a topping over an existing base, where the goal is permeability rather than load-bearing strength. 4" is the standard base under a driveway or heavy walkway — deep enough for the angular fragments to interlock and resist rutting once compacted. 6" or more suits a heavy-duty base under a driveway that will see truck traffic, or a freeze-thaw climate where frost heave is a concern; contractors often build a base that deep in two compacted lifts rather than one thick pour, since a single deep lift of crushed stone doesn't compact evenly all the way through. Whatever depth you use, measure it after compaction — loose crushed stone settles as the angular pieces shift and lock together, which the waste factor above is partly compensating for.

Common mistakes

• –Measuring depth as the loose pile height instead of the compacted depth — crushed stone settles as the angular pieces interlock under load.
• –Confusing crushed stone with gravel in density calculations. Crushed stone's angular shape packs tighter and typically weighs more per yard than rounded gravel.
• –Pouring a single thick lift instead of compacting in stages. A base deeper than about 4" compacts unevenly if it isn't built and compacted in layers.
• –Skipping the waste factor on irregular or sloped areas, where cutting and spillage run higher than a clean rectangle.
• –Ordering bagged crushed stone once a job runs past roughly a ton — bagged material typically costs 2-3x more per ton than a bulk delivery.

Where the density figure comes from

Select Sand & Gravel lists crushed stone specifically at 1.35–1.4 tons/yd³; North Bay Materials lists the broader gravel/sand category at 1.30–1.40 tons/yd³. Crushed stone's angular, fractured faces pack tighter than rounded gravel, so we anchor to the higher, stone-specific figure: 1.35–1.45 tons/yd³. Treat this as a floor rather than a ceiling — saturated or compacted material runs heavier than either published range. We use 1.4 tons/yd³ as the display figure, drawn from:

• Select Sand & Gravel — How Much Does a Yard of Crushed Stone Weigh?
• North Bay Materials — Landscape Material Density Calculator

Read more in our density methodology.

FAQ

How much crushed stone do I need for a driveway?

For a standard 4" compacted base, multiply the driveway's length and width in feet, divide by 3 (to get the volume in cubic feet at 4"), then divide by 27 for cubic yards. A 12 ft × 40 ft driveway at 4" needs about 5.9 cubic yards before waste — use the calculator above to add your waste factor and get a tonnage.

What's the difference between crushed stone and gravel?

Crushed stone is mechanically fractured rock with angular, jagged faces, while gravel is naturally weathered and rounded. That angularity lets crushed stone interlock and compact into a stable base, which is why it's preferred under driveways and structures, while gravel's rounded shape suits pathways and drainage where some shifting is fine.

Why does crushed stone weight per cubic yard vary so much?

Density depends on the stone's size, gradation, and how tightly it packs. A clean, single-size stone has more air gaps and weighs less; a dense-graded mix with fines fills those gaps and weighs more. That's why we show a range instead of one number — always confirm the exact figure with your supplier for a large order.

Should I measure loose or compacted depth?

Compacted. Crushed stone settles noticeably as its angular pieces shift and interlock under a plate compactor or vehicle traffic. Order based on the final, compacted depth you want, and let the waste factor cover the settling — that avoids running short partway through the job.

Is it cheaper to buy crushed stone in bags or bulk?

Bulk almost always wins past about a ton (roughly 27 bags at 0.5 cu ft each). Bagged crushed stone carries packaging and handling costs that can put it at 2-3x the price per ton of a bulk delivery. Bags make sense only for small repairs or projects without truck access.

How deep should a crushed stone base be?

A drainage layer or topping only needs about 2 inches. A driveway or heavy walkway needs a compacted base of 4 inches, and a driveway that will see regular vehicle or truck traffic — or sits in a freeze-thaw climate — often needs 6 inches or more, built and compacted in stages rather than as one deep lift.

How many truckloads of crushed stone will I need?

Divide your adjusted cubic yardage by the truck's capacity — most standard dump trucks carry about 10-14 cubic yards. The calculator above uses 12 cubic yards as a default and rounds up, since a partial truckload still requires a full trip.