Gravel Calculator
Gravel for a driveway, path or base: cubic yards, tons and bags for rectangles, circles, triangles, rings or a list of areas, with stone-type densities, compaction allowance, bulk vs bag cost and truckloads.
How it works
area: rectangle L × W · circle π × d² ÷ 4 · triangle b × h ÷ 2 · ring π × (D² − d²) ÷ 4 · cubic yards = area × depth(in) ÷ 12 ÷ 27 · order = cubic yards × (1 + extra%) · tons = cubic yards × density (t/yd³) · bags = weight ÷ bag weight, rounded up
Work out the area of each shape, multiply by the depth in feet (inches ÷ 12) to get cubic feet, and divide by 27 for cubic yards. List mode adds up several areas, and each rectangle can have its own depth. The extra percentage covers compaction and spreading losses. Quarries sell by the ton, so the volume is multiplied by the loose density of the stone you pick: 1.4 tons per cubic yard for ordinary gravel, up to about 1.85 for riprap and as little as 0.5 for lava rock. Bag counts divide that weight by the bag weight. The cost section prices the same order delivered in bulk and in bags, so you can see which is cheaper. Truckloads come from the truck capacity.
Worked example
A 20 × 10 ft parking pad 3 in deep: 200 sq ft × 0.25 ft = 50 cu ft, ÷ 27 = 1.85 cu yd. With 10% extra you order 2.04 cu yd. At 1.4 tons per cubic yard that weighs 2.85 tons. At $45 a ton plus $75 delivery the bulk order is $203.33. The same stone in 50-lb bags is 115 bags, or $575 at $5 a bag.
Sources: Inch Calculator — gravel weight per cubic yard by type · Omni Calculator — gravel density 1,680 kg/m³
Frequently asked questions
How deep should a gravel driveway be?
Plan on 4–6 in of compacted stone, usually in two layers: a coarse base such as crusher run under 2 in of finer top stone. Use List mode with a depth on each line to price both layers in one go. Paths and drainage beds can be 2–3 in deep. Go deeper on soft or clay soils.
Should I buy by the yard or the ton?
Most quarries price by the ton and most landscape yards by the cubic yard. The density list converts between them. Ordinary gravel is about 1.4 tons per cubic yard, so a $45 ton is about $63 a yard. Stone type and moisture change the density, so treat tonnage as an estimate and confirm with the supplier.
How much area does a ton of gravel cover?
At 1.4 tons per cubic yard, one ton is about 19 cu ft of stone. That covers about 77 sq ft at 3 in deep, 116 sq ft at 2 in, or 58 sq ft at 4 in. The calculator shows the figure for your depth and stone.
Are bags or bulk cheaper?
Bags win only for small jobs. A 50-lb bag holds about half a cubic foot, so a cubic yard is about 56 bags. At typical prices bulk is cheaper from about half a yard, even with a delivery fee. Enter both prices to see the break-even for your job.
Do I need landscape fabric under gravel?
For driveways and paths, yes. A woven geotextile stops the stone sinking into the soil and blocks weeds. That is what makes a gravel surface last instead of disappearing into mud.
Related calculators
Estimates only — add for waste and confirm against local building codes and supplier specs.