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Estimate cubic yards and tons of gravel for driveways, paths and landscaping from length, width and depth.
Enter the length and width of your area in feet and the desired depth in inches. The calculator finds the volume in cubic feet, converts it to cubic yards, and converts yards to tons.
Formula: Volume = length × width × (depth ÷ 12). Cubic yards = cubic feet ÷ 27. Tons = cubic yards × 1.35. Example: 10 × 10 ft at 3 in deep = 25 ft³ = 0.93 yd³ ≈ 1.25 tons.
Gravel is the backbone of driveways, patios, walkways, drainage systems, and countless landscaping projects, yet it is also one of the most frequently miscalculated materials in home improvement. Order too little and your project stalls while you wait for another delivery; order too much and you are left with an expensive pile of stone sitting in your yard for months. The difference between a smooth project and a costly headache usually comes down to one thing: knowing exactly how much gravel you need before you pick up the phone or visit the quarry. That is precisely what the Gravel Calculator above is designed to do. In a few seconds it converts the length, width, and depth of your project area into cubic yards and tons, giving you the numbers suppliers actually use when they quote prices and schedule deliveries. This in-depth guide explains how to use the calculator, the math behind it, and the practical details that separate an accurate estimate from a rough guess.
Using the Gravel Calculator is straightforward, but getting an accurate result depends on measuring carefully and understanding what each input means. Follow these steps for the most reliable estimate:
Gravel volume is the amount of three-dimensional space a layer of gravel occupies, and understanding it is the key to ordering the right quantity. Suppliers in the United States sell gravel by the cubic yard, which is a cube measuring 3 feet on each side and containing 27 cubic feet. Some suppliers, especially quarries, sell by the ton instead, which is a measure of weight rather than volume. Because different types of stone have different densities, the conversion between cubic yards and tons is not fixed: crushed limestone weighs roughly 1.4 tons per cubic yard, while pea gravel weighs about 1.3 tons per cubic yard and river rock can reach 1.5 tons per cubic yard.
Several physical factors affect how gravel behaves once it leaves the truck. Compaction is the settling of stone particles under their own weight, foot traffic, or vehicle traffic; a freshly dumped pile can lose 10 to 20 percent of its volume after compaction. The angle of repose describes how steeply a pile of gravel can sit before it slides, which matters when you estimate how a delivered pile will spread. Bulk density is the weight of gravel including the air voids between stones, and it is the figure suppliers use when converting your cubic-yard order into tons for the truck scale.
Gravel types also behave differently. Crushed stone has angular edges that lock together, making it ideal for driveways and load-bearing bases. Pea gravel consists of small, rounded stones that shift underfoot, which makes it comfortable for walkways but poor for driveways. River rock is larger and decorative, often used in beds and drainage features. Crusher run, also called dense graded aggregate, contains a mix of stone sizes plus stone dust that compacts into a nearly concrete-like surface, which is why road builders love it for bases. Knowing which type you are ordering matters because density differences of even 10 percent can change your tonnage by hundreds of pounds on a large project.
Finally, remember that sub-base preparation changes everything. Gravel spread over soft, uncompacted soil will sink, effectively increasing the depth you need. Professionals compact the soil first, sometimes adding a woven geotextile fabric to prevent the stone from migrating downward. A well-prepared base can reduce the gravel you need by 15 percent or more compared with dumping stone directly onto loose dirt.
The math behind the Gravel Calculator is simple geometry. First convert the depth from inches to feet by dividing by 12, then multiply length by width by depth to get cubic feet, and finally divide by 27 to convert cubic feet into cubic yards:
Volume (cubic yards) = (Length in feet × Width in feet × (Depth in inches ÷ 12)) ÷ 27
To convert cubic yards to tons, multiply by the material density. A widely used average for crushed gravel is 1.35 tons per cubic yard:
Weight (tons) = Volume in cubic yards × 1.35
Here are two worked examples showing every step:
Worked Example 1: A garden path measures 10 feet long, 10 feet wide, and you want 3 inches of gravel. Convert depth: 3 ÷ 12 = 0.25 feet. Multiply: 10 × 10 × 0.25 = 25 cubic feet. Convert to cubic yards: 25 ÷ 27 = 0.93 cubic yards. Convert to tons: 0.93 × 1.35 = 1.25 tons. Add a 10 percent allowance: 1.25 × 1.10 = 1.38 tons. You would order about 1.4 tons, or roughly 1 cubic yard.
Worked Example 2: A parking pad measures 30 feet long, 8 feet wide, with a 4-inch gravel layer. Convert depth: 4 ÷ 12 = 0.333 feet. Multiply: 30 × 8 × 0.333 = 80 cubic feet. Convert to cubic yards: 80 ÷ 27 = 2.96 cubic yards. Convert to tons: 2.96 × 1.35 = 4.0 tons. Add a 10 percent allowance: 4.0 × 1.10 = 4.4 tons. You would order about 4.5 tons, or 3 cubic yards.
Notice how a single inch of extra depth changes the result dramatically. In Example 2, increasing the depth from 4 inches to 5 inches would raise the volume from 80 to 100 cubic feet, which is a 25 percent increase in material and cost. That is why measuring depth carefully, rather than guessing, saves real money.
Let us walk through a complete, realistic driveway project. Suppose you are resurfacing a straight driveway that is 40 feet long and 12 feet wide, and you want a fresh 4-inch layer of crushed stone over the existing compacted base.
Step one: convert the depth to feet. Four inches divided by 12 equals 0.333 feet. Step two: multiply the dimensions. Forty times 12 times 0.333 equals 160 cubic feet. Step three: convert to cubic yards by dividing by 27. One hundred sixty divided by 27 equals 5.93 cubic yards. Step four: convert to tons using 1.35 tons per cubic yard. Five point nine three times 1.35 equals 8.0 tons. Step five: add the standard 10 percent allowance for compaction and spillage. Eight times 1.10 equals 8.8 tons, so you would order 9 tons to be safe.
Now translate that into money. If your local quarry charges 52 dollars per ton for delivered crushed stone, 8.8 tons costs about 458 dollars. If the supplier instead prices by the cubic yard at 65 dollars per yard, 5.93 cubic yards costs about 385 dollars before delivery fees. Always ask whether the quoted price includes delivery, because a 60-dollar delivery fee can erase the apparent savings of a cheaper per-ton price. Also confirm the minimum order: many quarries will not deliver less than 3 to 5 tons, and some charge a small-load fee below 10 tons.
One more driveway tip: if your driveway has ruts, potholes, or soft spots, fill and compact those areas first rather than burying them under extra gravel. A 2-inch-deep rut running the length of a 40-foot driveway quietly adds about 1 cubic yard to your order if you simply cover it, which is material you would never have needed with proper base preparation.
Now consider a backyard patio project. You are building a 14-foot by 12-foot patio and need a 3-inch bed of compacted gravel beneath the pavers to ensure drainage and a level surface.
Convert the depth: 3 divided by 12 equals 0.25 feet. Multiply: 14 times 12 times 0.25 equals 42 cubic feet. Convert to cubic yards: 42 divided by 27 equals 1.56 cubic yards. Convert to tons: 1.56 times 1.35 equals 2.1 tons. Add the 10 percent allowance: 2.1 times 1.10 equals 2.3 tons. For a project this size, you have a genuine choice between bulk delivery and bags.
Compare the two options with real numbers. Bulk delivery of 2.3 tons at 55 dollars per ton costs about 127 dollars, but you must check the supplier minimum; a 3-ton minimum at the same rate would cost 165 dollars. Bagged gravel from a home center typically comes in 0.5-cubic-foot bags costing around 4.75 dollars each. You need 42 cubic feet, which is 84 bags, for a total of 399 dollars. Bulk wins by a wide margin even with a minimum-order surcharge, but bags make sense if a dump truck cannot reach your backyard and you would otherwise pay for wheelbarrow labor anyway.
For patios, also remember the edge restraint. Gravel migrates outward under the pressure of pavers and foot traffic, so install metal or plastic paver edging before you spread the stone. Without edging, you can lose half an inch of effective depth at the perimeter within a single season, which is exactly the kind of slow material loss that makes patios develop dips and puddles.
1. Mixing up inches and feet. The single most common error is entering the depth in feet instead of inches, or forgetting to divide by 12. A 4-inch depth entered as 4 feet overstates your order by a factor of 12, turning a 400-dollar delivery into a 4,800-dollar disaster. Always double-check your units before you calculate.
2. Ignoring compaction. Freshly dumped gravel looks like far more material than it really is because it is full of air voids. After a few rainstorms and some vehicle traffic, a 4-inch layer can settle to barely 3 inches. Failing to add a 10 to 15 percent compaction allowance means coming up short, which is why so many driveways look thin just months after installation.
3. Measuring only the visible rectangle. Driveways flare at the street, patios have curved edges, and walkways widen at gates. If you measure only the neat central rectangle, you can easily miss 10 to 20 percent of the actual area. Walk the full perimeter with your tape measure and include every flare, curve, and apron in your measurements.
4. Using one density for every stone type. Pea gravel, crushed limestone, river rock, and crusher run all have different bulk densities, ranging from about 1.25 to 1.55 tons per cubic yard. Using a generic 1.5 tons per yard for lightweight pea gravel can overstate your order by 200 pounds per cubic yard, which adds up to real money on a 20-ton driveway.
5. Forgetting the base and the edges. Gravel spread on soft soil sinks, and gravel without edging spreads. Skipping soil compaction or edge restraints does not just waste material; it guarantees you will be topping up the surface every year. Spend the time on the base once, and your initial calculation stays accurate for years.
Gravel is rarely the only material on a project. Use our Concrete Calculator to estimate ready-mix or bagged concrete for footings, slabs, and paver bases, try the Mulch Calculator when you are finishing beds and borders around your new hardscape, or browse the full Construction Calculators collection for tools covering sand, topsoil, and more.
This page provides a Gravel Calculator that converts project dimensions (length in feet, width in feet, depth in inches) into gravel volume in cubic feet and cubic yards, plus estimated weight in tons using a bulk density of approximately 1.35 tons per cubic yard for crushed gravel. Core formulas: Volume (cu yd) = (L × W × (D/12)) / 27; Weight (tons) = Volume (cu yd) × 1.35. A 10% allowance for compaction and waste is standard. Page topic: calculating gravel quantity for driveways, patios, walkways, and landscaping. Last reviewed October 2026.
At 3 inches deep: 10 × 10 × 0.25 = 25 cubic feet = 0.93 cubic yards, about 1.25 tons. Enter your dimensions in the gravel calculator above.
About 1.35 tons per cubic yard for typical crushed gravel. Denser stone runs heavier — check with your supplier.
3–4 inches for paths and patios; 4–6 inches for driveways that carry cars. Deeper bases compact better and rut less.
Yes — order 5–10% more than calculated for settling, compaction and uneven ground. A short load costs more than a little extra.
Crushed stone has angular edges that lock together and compact firmly; rounded pea gravel shifts more. Both are estimated the same way by volume.
In most U.S. markets, gravel costs between $30 and $60 per cubic yard for the material itself, plus a delivery fee of roughly $50 to $100 per truckload. Crushed limestone and crusher run sit at the cheaper end, while decorative pea gravel and river rock cost more. Ordering 10 tons or more often unlocks a lower per-ton rate, so combining projects can reduce the unit price.
One cubic yard equals 27 cubic feet. With standard
0.5-cubic-foot bags you need 54 bags, and with 0.75-cubic-foot bags you need 36 bags. Beyond about one cubic yard, bulk delivery from a quarry is far cheaper per unit than buying bags.
On bare soil, yes. A woven geotextile fabric keeps the stone from sinking into mud, blocks weeds, and can cut the gravel you need by up to 15 percent. On an already compacted driveway base it is optional, but it still extends the life of the surface.
Sources and methodology: volume uses the standard cubic-yard formula (length × width × depth ÷ 27); weight uses a bulk density of about 1.35 tons per cubic yard for crushed gravel, consistent with U.S. aggregate supplier data. Content last reviewed October 2026.
Also try our Concrete Calculator and Mulch Calculator.