Stone Calculator

A stone calculator turns the length, width and depth of your project into cubic yards and tons of crushed stone. A 30 ft × 12 ft driveway at 4 inches deep needs 4.44 cubic yards, which is about 6.22 tons of #57 stone at 1.4 tons per cubic yard, or roughly 6.84 tons once you add 10% for spillage and uneven ground.

That is the whole job of this crushed stone tonnage calculator: give it a footprint and a finished depth, pick the grade you are buying, and read off the tons to order. Quarries sell crushed stone by the ton far more often than by the cubic yard, which is why tons lead the result; cubic yards, cubic feet and the bag count sit right underneath.

How the calculation works

Every stone estimate is two steps: a volume, then a conversion of that volume to weight. The volume step is:

Length and width are measured in feet, depth in inches (divided by 12 to become feet), and the cubic feet are divided by 27, because a cubic yard is a 3 ft × 3 ft × 3 ft cube. The weight step multiplies those cubic yards by the density of the stone:

Loose crushed stone such as #57 runs about 1.4 tons per cubic yard, which is 2,800 lb per cubic yard or about 104 lb per cubic foot, inside the 2,700 to 3,000 lb per loose cubic yard the U.S. Army's earthmoving manual (FM 5-434) gives for dry gravel. Compacted stone is heavier, because rolling squeezes out the air between the pieces: the Ohio Department of Transportation converts crushed stone in its Item 411 base at 3,800 lb (1.9 tons) per cubic yard compacted in place, and that is the calculator's crusher run preset. Because the exact number depends on the quarry, the moisture in the pile and how the load was measured, the density field is fully editable: type in whatever your supplier quotes and the tons update instantly.

Worked example: a 30 ft × 12 ft driveway at 4 inches

Say you are re-stoning a single-car driveway that measures 30 ft long by 12 ft wide, and you want a fresh 4-inch layer of #57 stone. Start with the area: 30 × 12 = 360 sq ft. Convert the depth: 4 ÷ 12 = 0.333 ft. Volume: 360 × 0.333 = 120 cubic feet, and 120 ÷ 27 = 4.44 cubic yards. At 1.4 tons per cubic yard that is 4.44 × 1.4 = 6.22 tons, or 12,444 lb. Add the 10% allowance and the order becomes 6.84 tons (4.89 cubic yards). If you were buying bags instead, the same job would take 249 bags of 50 lb exact, or 274 bags with the allowance, which is a clear signal that this is a bulk-delivery job.

A second example: a walkway in #8 stone

Smaller stone, smaller job. A garden walkway 40 ft long and 4 ft wide at 3 inches deep is 160 sq ft × 0.25 ft = 40 cubic feet, or 1.48 cubic yards. Loose #8 stone weighs about the same as #57, so at 1.4 tons per cubic yard that is 2.07 tons (4,148 lb), and 2.28 tons with the 10% allowance. In bags, that is 83 bags of 50 lb exact or 92 bags with the allowance. At that size it is worth pricing both: a ton is 40 bags, so multiply the bag price by 40 and compare it with the delivered price per ton.

Tons of crushed stone by area and depth

This table gives the tons of loose crushed stone for common footprints at the four most-used depths, computed with the formula above at 1.4 tons per cubic yard and before any allowance. Find your square footage, read across to your depth, then add about 10% when you order:

Notice that tonnage scales exactly with both area and depth: 500 sq ft at 4 inches (8.64 tons) needs the same stone as 1,000 sq ft at 2 inches. For compacted crusher run at 1.9 tons per cubic yard, multiply any cell by 1.9 ÷ 1.4 (about 1.36), or simply pick the crusher run preset in the calculator.

Common crushed stone sizes and what they are for

Crushed stone in the US is sold by size number. The numbers come from the standard sizes of coarse aggregate in AASHTO M 43 and ASTM D448, which state DOTs and quarries use; each one names the largest and smallest piece size. The size decides what the stone is good for; the density decides how many tons a given volume weighs:

Product names for the dense-graded mix are not standardized: #411 is also sold as crush and run, crusher run, aggregate base or road base depending on the region, and in Ohio the number matches the state DOT's Item 411, stabilized crushed aggregate. The presets set a typical density for each grade, but the right move is always to ask the yard what its material weighs per cubic yard and type that number in.

How to use this stone calculator

1. Length and width (feet): measure the footprint at its longest and widest points. For a rough or curved area, break it into rectangles and add them, or use the Square Footage Calculator first.
2. Depth (inches): enter the finished thickness you want. The 2", 3", 4" and 6" buttons cover most paths, patios and driveways.
3. Stone type: tap the grade you are buying. Each preset fills in a typical density: 1.4 tons per cubic yard for loose #57, #8 and #2/#3; 1.9 for crusher run compacted in place; 1.5 for loose stone dust.
4. Density: overwrite the preset with your supplier's number if they give one. The note under the field shows the same density in pounds per cubic yard and per cubic foot.
5. Waste allowance: leave it on +10% for a normal order, or switch to Exact if you only want the raw quantity, for example when comparing quotes.
6. Bag size: choose 50 lb bags (sold by weight) or 0.5 cubic foot bags (sold by volume) to see how many bags the job would take.

The result updates as you type: the tonnage to order on top, then exact weight and volume, bag count, a coverage check for one ton at your depth, and tons at other depths for the same footprint.

Who this calculator is for

• Homeowners topping up or building a crushed stone driveway, parking pad or fire-pit area.
• Landscapers quoting walkways, dry creek beds, French drains and drainage trenches by the ton.
• Paver and patio installers sizing the crusher run base and stone-dust setting bed as separate layers.
• Contractors ordering #2 or #3 stone for a construction entrance or a soft-ground first lift.
• Anyone comparing quotes who needs the same job in tons for one supplier and cubic yards for another.

Key terms explained

• Ton: in this calculator a US short ton of 2,000 lb, the unit quarries and landscape yards quote for bulk stone.
• Cubic yard (yd³): a 3 ft cube, equal to 27 cubic feet, the other common bulk unit.
• Density: the weight of a cubic yard of stone. It links the volume you measured to the tons you pay for, and it is the number most likely to differ from the default.
• Fines: the dust and very small particles in a crushed product. Clean stone (#57, #8) has almost none; crusher run and screenings are full of them, which is why they compact and weigh more.
• Loose vs. compacted: stone in a truck or pile is loose; after spreading and rolling it is compacted and weighs more per cubic yard. The crusher run preset already uses a compacted density.

How much area does a ton of stone cover?

Coverage is the tonnage question turned around, and it is handy when a supplier says "you will need about five tons" and you want to check. One cubic yard covers 27 cubic feet divided by the depth in feet, and one ton covers that area divided by the density:

Denser material covers less per ton: compacted crusher run at 1.9 tons per cubic yard covers about 26% less area per ton than loose #57, because each ton fills a smaller volume.

Density: tons, pounds and cubic yards side by side

Because the density field accepts any value, it helps to see what common figures mean in other units. Each row converts one density into pounds per cubic yard, pounds per cubic foot, and the cubic yards you get per ton:

On the 30 ft × 12 ft driveway from the worked example, the same 4.44 cubic yards is 5.78 tons at 1.3, 6.22 tons at 1.4, 6.67 tons at 1.5 and 8.44 tons at 1.9 tons per cubic yard. A density guess that is off by 0.1 moves a driveway-sized order by close to half a ton, which is why the field is editable.

Building a driveway in layers

A crushed stone driveway that lasts is rarely one layer. A common build is about 4 inches of compacted #411 crusher run as the base, then 2 to 3 inches of #57 on top; on soft or wet ground a first lift of #2 or #3 stone may go underneath. Each layer has its own depth and density, so run the calculator once per layer and add the results. For the 30 ft × 12 ft driveway: a 4-inch compacted crusher run base at 1.9 tons per cubic yard is 4.44 cubic yards or 8.44 tons, and a 2-inch top of loose #57 at 1.4 is 2.22 cubic yards or 3.11 tons, for 11.56 tons in total and about 12.71 tons with the 10% allowance. Compact each layer before the next goes down. If the finished surface will be poured rather than left as loose stone, size the base here and the slab with the Concrete Calculator.

Factors that change the result

• Depth: the most sensitive input, because it multiplies the volume directly. Going from 3 to 4 inches on the example driveway raises the stone from 4.67 to 6.22 tons; going to 6 inches takes it to 9.33 tons.
• Area: length and width set the footprint. A tape-measure error of one foot on a 12-foot width is an 8% error in the whole order.
• Density: changes the tons but never the cubic yards. It matters whenever you buy by weight, and it is the input that varies most between suppliers.
• Loose vs. compacted: a compacted base needs more tons per cubic yard of finished depth than loose stone; that is why crusher run uses 1.9.
• Sub-grade condition: soft, wet or rutted ground swallows stone before you reach the finished depth, sometimes more than the 10% allowance covers.

Practical tips

• Order in the supplier's unit. Most quarries sell by the ton; some landscape yards sell by the cubic yard. Quote the matching number and you avoid rounding disputes at delivery.
• Keep the 10% allowance on for any real order. Switch it off only to compare bare quantities between quotes.
• Ask for the density in writing. The scale ticket shows the delivered weight, so knowing the tons per cubic yard lets you check that the load matches the volume you need.
• Compare bulk and bags properly. A ton is 40 bags of 50 lb: multiply the bag price by 40 and compare it with the delivered price per ton, including the delivery fee.

Limitations and assumptions

• It assumes a level, rectangular area at one uniform depth. Slopes, dips and odd shapes need averaging or splitting into rectangles.
• Density is an estimate. The presets are typical values; the actual weight of a cubic yard depends on the quarry, gradation, moisture and compaction.
• It calculates one layer at a time. Multi-layer driveways and paver bases need a separate run for each material.
• The 10% allowance is a general figure for spillage and uneven ground; very soft sub-grade or a rough existing surface can need more.
• Delivery charges, edging, geotextile fabric, labor and equipment are not included.

Related calculators

Use this stone calculator when the material is crushed, angular stone sold by grade number and priced by the ton. Reach for the Gravel Calculator when you are buying rounded or washed gravel such as pea gravel and want cubic yards as the headline figure; the volume math is identical, but the density presets and the focus differ. For a patio, the Paver Calculator sizes the pavers, base gravel and sand together, and the Sand Calculator converts the same dimensions at sand's own density. The Cubic Yard Calculator handles any bulk material by volume alone, the Topsoil Calculator and Mulch Calculator cover the softer landscape fills, and the Asphalt Calculator takes over when the stone base gets a paved surface instead of staying exposed.

Sources

• U.S. Department of the Army: FM 5-434, Earthmoving Operations (June 2000, PDF copy), Table 1-2: dry gravel 2,700 to 3,000 lb per loose cubic yard.
• Ohio Department of Transportation: Construction and Material Specifications, Item 411 Stabilized Crushed Aggregate (3,800 lb per cubic yard for crushed stone, compacted in place).
• Federal Emergency Management Agency: Appeal decision on gravel road quantities (1.4 tons per cubic yard for uncompacted gravel at 104 lb per cubic foot, against 140 lb per cubic foot for compacted Class A crushed stone in the Iowa DOT Design Manual).
• AASHTO M 43 / ASTM D448, standard sizes of coarse aggregate (size 57: 1 in. to No. 4; size 8: 3/8 in. to No. 8; size 3: 2 in. to 1 in.; size 2: 2 1/2 in. to 1 1/2 in.), as adopted in state DOT specifications.
• National Institute of Standards and Technology: NIST Handbook 44 (2026), Appendix C (PDF) (27 cubic feet = 1 cubic yard, 2,000 pounds = 1 short ton).