Methodology
Every material calculator on the site works in the same three steps. Volume first, then weight, then the units a supplier actually sells. Here are the formulas, the allowances added on top, and the material weights those calculators use.
Step one: area and depth into cubic yards
Square feet × depth in inches ÷ 12 gives cubic feet. Divide that by 27, the cubic feet in a cubic yard, and you have cubic yards.
Take a bed 10 ft by 10 ft, filled 3 inches deep. That is 100 sq ft, so 100 × 3 ÷ 12 = 25 cubic feet, and 25 ÷ 27 = 0.93 cubic yards.
A circle uses π × radius² for the area, measured straight across and halved. An odd shape is best split into rectangles and added up. Depth is always in inches, because that is how a bed, a path or a base course gets specified.
Step two: cubic yards into tons
Cubic yards × the material’s weight per cubic yard ÷ 2,000 gives US tons. The weight is the part that changes from page to page, and it is why there is no single answer to “how many tons in a yard”.
The same 0.93 cubic yards of 1–3 inch river rock, at 2,700 lb a yard, comes to 1.25 tons. In play sand it would be lighter, in fill sand heavier, though the hole is identical.
Step three: volume into bags and loads
Bagged material is sold by volume, so the bag count is cubic feet ÷ the volume printed on the bag. Stone usually comes in 0.5 cu ft bags, which is 54 to the cubic yard. Bagged topsoil is often 0.75 cu ft, or 36 to the yard.
Bag counts and truck trips always round up to a whole bag or a whole trip, since nobody sells two-thirds of one.
Allowances on top of the raw volume
The raw volume is rarely what you should order. These calculators add an allowance, and each lets you see or change the one it applies.
- Overage on river rock: 10% by default, for settling and uneven ground.
- Compaction on fill dirt: 15% for sandy or gravelly fill, 20% for general fill / loam, 30% for clay-heavy fill. Loose dirt loses that much volume once it settles, so the order is the hole × (1 + the percentage).
- Compaction on decomposed granite: 20% for loose DG, 25% for stabilized DG, 25% for resin-coated DG, the volume it loses under a plate compactor.
- Compaction on paver base and crushed concrete: 20% and 20%, for the same reason.
- Cutting waste on flagstone: 8% for cut / dimensional, 20% for irregular, tight joints, 12% for irregular, open joints, 5% for stepping stones.
Boulders and flagstone: solid stone by the cubic foot
Boulders and flagstone are solid stone, so they are weighed by the cubic foot of rock rather than the cubic yard of a loose pile.
Boulders: length × width × height in feet gives the box the stone would fit in. A boulder never fills its box, so that volume is multiplied by a shape factor (0.8 for blocky / quarried, 0.65 for irregular (typical), 0.52 for rounded / egg, 0.7 for flat / sitting stone), then by the stone’s weight per cubic foot.
Flagstone: thickness in inches ÷ 12 × the stone’s weight per cubic foot gives pounds per square foot. Multiply by the patio area, add the cutting waste above, and divide by 2,000 for tons.
| Stone | Weight per cubic foot |
|---|---|
| Granite | 165 lb |
| Limestone | 160 lb |
| Sandstone | 145 lb |
| Moss rock | 160 lb |
| Fieldstone / glacial | 165 lb |
| Basalt / trap rock | 180 lb |
| Quartzite | 165 lb |
| Stone | Weight per cubic foot |
|---|---|
| Sandstone (Arizona, Oklahoma) | 145 lb |
| Pennsylvania bluestone | 165 lb |
| Limestone | 160 lb |
| Quartzite | 165 lb |
| Slate | 175 lb |
| Granite | 165 lb |
The weights we use
These are typical dry weights per cubic yard, except where a moisture state is named. Real loads vary by quarry and by weather, often by a couple of hundred pounds a yard, so check with your supplier before ordering anything close to a truck’s limit.
| Material | Weight per cubic yard |
|---|---|
| #57 stone (3/4") | 2,800 lb |
| 3/4" clean (3/4") | 2,800 lb |
| #8 stone (3/8") | 2,750 lb |
| #4 stone (1–1.5") | 2,750 lb |
| Crusher run (3/4" minus) | 3,000 lb |
| Pea gravel (3/8") | 2,700 lb |
| River rock (1–3") | 2,700 lb |
| Decomposed granite (Fines) | 3,000 lb |
| Material | Weight per cubic yard |
|---|---|
| 3/4"–1" (pea-size) | 2,800 lb |
| 1"–3" (most common) | 2,700 lb |
| 2" | 2,700 lb |
| 3"–5" | 2,500 lb |
| Material | Weight per cubic yard |
|---|---|
| 21AA (1" to fines) | 2,400 lb |
| 6A (1/4" to 1") | 2,300 lb |
| 1" minus (1" to fines) | 2,400 lb |
| Road base (2" to fines) | 2,500 lb |
| Fines / screenings (Under 1/4") | 2,600 lb |
| Material | Weight per cubic yard |
|---|---|
| Masonry / mason sand | 2,700 lb |
| Concrete / sharp sand | 2,600 lb |
| Paver bedding sand | 2,700 lb |
| Play sand | 2,400 lb |
| Fill sand | 2,900 lb |
| Leveling / topdressing sand | 2,600 lb |
| Material | Weight per cubic yard |
|---|---|
| Dry / screened | 2,000 lb |
| Moist (typical delivery) | 2,200 lb |
| Wet, after rain | 2,700 lb |
| Material | Weight per cubic yard |
|---|---|
| Fill dirt, typical | 2,000 lb |
| Material | Weight per cubic yard |
|---|---|
| Garden / yard waste compost | 1,000 lb |
| Mushroom compost | 1,200 lb |
| Composted manure | 1,400 lb |
| Compost and topsoil blend | 1,800 lb |
| Mulch | Dry | Wet |
|---|---|---|
| Shredded hardwood | 600 lb | 900 lb |
| Dyed black or brown | 600 lb | 900 lb |
| Cedar | 550 lb | 825 lb |
| Cypress | 400 lb | 600 lb |
| Pine bark nuggets | 450 lb | 630 lb |
| Rubber mulch | 1,150 lb | 1,150 lb |
Water is the biggest variable. Topsoil gains several hundred pounds a yard after rain, which can decide whether a load is legal in a given truck. Stone gains less: river rock picks up about 12% when it has been rained on.
Prices
Price ranges on the site are typical 2026 US figures. They move with region, with haul distance from the quarry or yard, and with the season, so read them as a way to sanity-check a quote rather than as the quote itself. The cost pages list delivery apart from the material where they can, since a blended figure hides which of the two is high.
What this page does not cover
The lawn calculators (lawn area, grass seed, mowing time, acres per hour, mowing cost and calories burned) work from rates, such as seed per 1,000 square feet or acres an hour, rather than from volume and weight, so the formulas above do not apply to them. Each one shows its working on its own page.
Published standards we follow
Where a published standard covers a figure, the calculators use it rather than an estimate.
- Minimum depths for loose-fill surfacing under play equipment follow the US Consumer Product Safety Commission’s Public Playground Safety Handbook. The depth for a specific piece of equipment depends on its fall height, tested under ASTM F1292.
- Calories burned mowing use MET values from the Compendium of Physical Activities, lawn and garden category.
If a figure looks wrong
Email support@landscapingcalculators.com with the page, the figure and, if you have one, the supplier spec sheet that disagrees with it. Alex Tim checks every correction, and because every page reads from the same table, a fix made once applies everywhere. More about who runs the site is on the about page.