The following calculator helps estimate the amount of gravel needed to cover an area based on the density and desired depth of the gravel. It also estimates the cost of purchasing a given amount of gravel.
A gravel calculator answers the question that stops most driveway, patio, and landscaping projects before they start: how much material do I actually order? Gravel is sold by volume in some places and by weight in others, quoted per cubic yard, per ton, per cubic meter, or by the bag depending on the supplier. Meanwhile the area you want to cover is measured in feet or meters and the depth in inches or centimeters. This calculator reconciles all of it. Enter the area you are covering, how deep you want the gravel, and what kind of gravel it is, and it returns the volume in cubic feet, cubic yards, cubic meters, and liters, the weight in pounds, tons, kilograms, and metric tons, and - if you enter a price - the total material cost in whatever unit your supplier quotes.
Getting the quantity right matters more than it might seem. Order too little and you face a second delivery charge that can rival the cost of the material itself, plus a visible seam where the new gravel meets the old. Order too much and you are left with a pile you have to store, spread somewhere it is not wanted, or pay to remove. Because gravel is heavy and delivery is priced by the load, the cost of guessing is real.
The calculator offers three ways to describe the area you are covering, selected with the radio buttons at the top:
Then set the remaining fields:
Every length, area, and depth field has its own unit dropdown, so you can mix and match freely - a driveway measured in feet with a depth specified in centimeters works exactly as you would expect.
The calculation itself is straightforward volume geometry followed by a density conversion.
Step 1 - Find the area. For a rectangle, area = length × width. For a circle, area = π × (diameter ÷ 2)². If you entered a total area directly, this step is already done.
Step 2 - Multiply by depth to get volume. Volume = area × depth, with both converted to consistent units first. This is the step where most manual estimates go wrong, because depth is almost always given in inches while area is in square feet. Three inches is a quarter of a foot, not three feet - so 200 square feet at 3 inches deep is 50 cubic feet, not 600.
Step 3 - Multiply by density to get weight. Weight = volume × density. Gravel is typically around 1,680 kg/m³ (about 105 lbs/ft³), so a cubic meter of gravel weighs roughly 1.7 metric tons. This step is what lets you convert a volume-based measurement into the tonnage most bulk suppliers actually sell by.
A worked example: a driveway 20 meters long and 15 meters wide, covered 3 cm deep. The area is 300 m², the depth is 0.03 m, so the volume is 9 m³ - equivalent to 9,000 liters, 11.77 cubic yards, or 317.8 cubic feet. At a gravel density of 1,680 kg/m³, that is 15,120 kg, or about 15.12 metric tons.
Density is the bridge between volume and weight, and it is the input people most often get wrong. The calculator offers four presets:
Real density varies with the stone type, how loosely the material is packed, moisture content, and the grading of the particle sizes. Crushed granite, limestone, and river rock all differ. If your supplier gives you a specific figure, use the "Use your own density" option - it will always be more accurate than a generic preset.
One important distinction: the presets describe loose density, the state gravel is in when delivered and spread. Once compacted, the same mass occupies noticeably less volume, which is why a compacted base layer needs more material than an uncompacted depth calculation suggests.
Depth is the input with the largest effect on cost, because it scales the volume linearly - doubling the depth doubles the material and doubles the bill. Typical depths:
For layered driveways, run the calculator once per layer with that layer's depth and gravel type, since the base course and the decorative top course are usually different materials at different prices.
Bulk delivery is dramatically cheaper per unit and is the standard choice for anything beyond a small garden feature. Suppliers quote by the cubic yard or by the ton and deliver by truck. The break-even point is usually somewhere around half a cubic yard - beyond that, bags stop making economic sense. Bear in mind that delivery is often charged per load and that trucks have both minimum and maximum capacities, so ordering slightly more to fill a load can cost less than ordering slightly less and paying for a second trip.
Bagged gravel costs considerably more per unit but makes sense for small jobs, for projects with no truck access, or when you need to carry material by hand to an awkward location. Bags typically come in 0.5 cubic foot volumes or 50 lb weights. Set the price unit to "per bag" and enter your bag size, and the calculator will tell you how many bags to buy - always rounding up, since suppliers do not sell fractions of a bag.
When comparing quotes, watch the units carefully. A price per ton and a price per cubic yard are not directly comparable without knowing the density, and this is a common source of confusion when shopping between suppliers. The calculator makes the comparison easy: enter each supplier's price in their own unit and compare the resulting totals.
The calculator returns the exact volume required to fill the space you described. In practice you should order somewhat more, for several reasons:
A practical approach is to add 5% to 10% for decorative applications and 10% to 20% for compacted structural layers. Rounding up to the nearest half or full cubic yard is usually sensible, since that is how bulk material is sold anyway.
Good preparation determines whether gravel stays where you put it. Excavate to the full planned depth rather than piling gravel on top of existing soil or turf, or the material will sink and disappear within a season. Grade the base so water drains away from buildings, and compact the sub-base before adding any gravel.
Landscape fabric between the soil and the gravel is worth the modest cost. It suppresses weeds and, more importantly, stops the gravel from being pushed down into soft soil over time, which is the most common reason a gravel surface needs topping up every year.
Edging - metal, plastic, timber, or stone - keeps gravel contained and gives a clean line. Without it, gravel gradually spreads outward into lawns and beds, and you lose depth where you need it most. For driveways, build the surface up in layers, compacting each one before adding the next; a single thick layer never compacts properly all the way through.
Crushed stone has angular, freshly fractured faces that lock together when compacted, making it the best choice for driveways, bases, and anywhere that needs to bear load and stay put.
Pea gravel is small, rounded, and smooth. It is comfortable underfoot and attractive, but because the stones are round they roll rather than lock, so it migrates easily and needs firm edging. It suits paths and play areas better than driveways.
River rock is larger, rounded, and decorative. It is generally used as ground cover and in drainage features rather than as a walking surface.
Crusher run (also called quarry process or hardcore) is a mixture of crushed stone and stone dust. The fines fill the voids and it compacts into a nearly solid surface, which makes it excellent as a base layer but less attractive as a finish.
Drainage stone is clean, angular, and washed free of fines so water passes through freely. Use it in French drains and around foundations, where fines would clog the void space and defeat the purpose.
Roughly 2,800 lbs, or about 1.4 short tons, at a typical gravel density of 105 lbs/ft³. A cubic meter weighs about 1,680 kg, or 1.68 metric tons. The exact figure depends on the stone type and moisture content - wet material can be noticeably heavier.
At 2 inches deep, one short ton of gravel covers roughly 100 square feet. At 3 inches, about 65 square feet; at 4 inches, about 50. Rather than relying on these rules of thumb, enter your actual area and depth above - the answer accounts for your specific density and units.
A cubic yard is 27 cubic feet, so it takes 54 bags of the common 0.5 cubic foot size. By weight, a cubic yard weighs around 2,800 lbs, which is about 56 of the standard 50 lb bags. This is why bulk delivery is so much cheaper for anything larger than a small project.
Yes. Add 5% to 10% for decorative ground cover and 10% to 20% for driveways and compacted base layers, to allow for settling, uneven ground, and spillage. Running short mid-project usually means paying a second delivery fee, which typically costs far more than the extra material would have.
Four to six inches total for a normal residential driveway, ideally built in two or three compacted layers with a coarse base beneath a finer top course. Driveways that carry heavy vehicles need 8 to 12 inches. Calculate each layer separately, since the base and surface materials usually differ in type and price.
No - it returns the exact volume needed to fill the space at the depth you specify. Because gravel settles under compaction and traffic, add a margin on top of the calculated figure, typically 10% to 20% for compacted layers.
Yes. The volume calculation is identical for any loose material - only the density changes. Dry sand and wet sand are included as presets, and you can enter any density for other materials. Topsoil runs roughly 1,200 to 1,400 kg/m³ and mulch is far lighter, around 250 to 400 kg/m³.
Bulk material is weighed on a truck scale, which is faster and more precise than measuring volume. The two are connected by density, which is exactly the conversion this calculator performs - enter your area and depth and it reports both the volume and the weight, so you can order in whichever unit your supplier uses.
This Gravel Calculator is provided for educational and general informational purposes only and produces estimates rather than exact quantities. Actual requirements vary with the type of gravel, how loosely or tightly it is packed, moisture content, ground conditions, and compaction. Always confirm quantities and densities with your supplier before ordering, and consult a qualified professional for structural applications such as driveways, foundations, and drainage systems.