Stone Calculator
Multiply the area by the depth to get cubic yards, then multiply by the stone's tons per cubic yard. A 200 square foot bed of river rock, 3 inches deep, needs about 2.70 tons with 10 percent extra.
This tool is part of our project calculators. Building a patio? Pair it with the paver calculator.
- Updated November 2026
- Sources Cited
- No Login Required
- Free to Use
Your stone order
Stone to order
2.7 tons
About 2.04 cubic yards for 200 sq ft.
- Cubic feet (before extra)
- 50
- Cubic yards (before extra)
- 1.852
- Cubic yards to order
- 2.04
- Pounds
- 5,398
- One ton covers
- 81.5 sq ft
- Tons per cubic yard
- 1.325
Planning numbers. Density varies by quarry and moisture. Mortar, sand and delivery are not counted.
Tons by stone type
Eight stone types, each with its own tons per cubic yard.
Flagstone and veneer
Flagstone by thickness and veneer by wall area, not just loose stone.
Coverage per ton
See how many square feet one ton covers at your depth.
Planning numbers, not a quote. Need gravel or crushed stone for a base? Use the gravel calculator.
How to Read the Result
The big number is the stone to order in tons. For loose stone and flagstone it is the volume of your bed, plus the extra you chose, times the weight of the stone. For full veneer it is a range, because the source gives a range of coverage per ton.
- Cubic yards to order is the volume your supplier may quote by instead of by weight.
- Pounds is the tons figure times 2,000. It helps when you check a delivery ticket.
- One ton covers shows how far a ton spreads at your depth, before the extra.
- Thin veneer shows a single figure, because you enter the supplier's coverage per ton.
Not sure of the area? Use the square footage calculator to measure an odd shape first.
How the Stone Calculator Works
The calculator finds a volume, then turns it into weight with a density for the stone you picked. Veneer is different: it is sold by the area it covers, so the tool divides your wall area by the coverage per ton. Each rule below names its source.
Volume from area and depth
Cubic feet = area in square feet x depth in inches / 12. Cubic yards = cubic feet / 27. The cubic yards to order equal that volume times one plus your extra. If you only need volume, the cubic yards calculator does the same first step.
Tons from stone density
Tons = cubic yards to order x tons per cubic yard. River rock and granite are 1.325 tons per cubic yard, marble is 1.35 and lava rock is 0.5. ProGreen Services publishes these supplier values. They are not exact, because density changes with the quarry and with moisture.
Flagstone by thickness
Flagstone and building stone weigh about 133 pounds per cubic foot, or 15 cubic feet per ton, per ProGreen Services. The calculator uses your thickness: tons = area x thickness in inches / 12 x 133 / 2,000. A thinner stone spreads farther per ton than a thick one.
Veneer by wall area
Veneer tons = (wall area minus openings) x (1 + extra) / coverage per ton. Halquist Stone says full veneer averages 35 to 40 square feet per ton, so the tool shows a range. For masonry units sold by count, use the brick calculator.
Stone Calculator Example with Real Numbers
A garden bed measures 20 by 10 feet and gets 3 inches of river rock. With 10 percent extra it needs 2.04 cubic yards, or 2.70 tons. One ton covers about 81.5 square feet at that depth.
| Output | Value | How it is found |
|---|---|---|
| Area | 200 sq ft | 20 ft x 10 ft |
| Cubic feet | 50.0 | 200 x 3 / 12 |
| Cubic yards | 1.852 | 50 / 27 |
| Cubic yards to order | 2.04 | 1.852 plus 10 percent |
| Tons to order | 2.70 | 2.037 x 1.325 tons per cubic yard |
| One ton covers | 81.5 sq ft | 200 / (1.852 x 1.325) |
Two more cases. A 100 square foot flagstone patio at 2 inches thick weighs 1.11 tons, and one ton covers 90.2 square feet. A 120 square foot wall of full veneer with 10 percent extra needs 3.30 to 3.77 tons.
ProGreen Services lists 110 to 130 square feet per ton for Buff Patio flagstone and states no depth. That figure has no stated depth, so it cannot be compared with the 2 inch case directly. Use the thickness your supplier quotes.
Stone Weight by Material
Stone weight swings a lot by type. Lava rock is 0.5 tons per cubic yard and marble is 1.35, which is nearly three times as heavy. The table shows each type and how far a ton spreads at 3 inches deep.
| Stone | Tons per cubic yard | Pounds per cubic yard | Sq ft per ton at 3 in |
|---|---|---|---|
| River rock | 1.325 | 2,650 | 81.5 |
| Granite | 1.325 | 2,650 | 81.5 |
| Marble | 1.35 | 2,700 | 80.0 |
| Lime rock (919) | 1.25 | 2,500 | 86.4 |
| 57 and 89 stone | 1.2 | 2,400 | 90.0 |
| Crimson | 1.1 | 2,200 | 98.2 |
| Eastern Sunrise | 0.9 | 1,800 | 120.0 |
| Lava rock | 0.5 | 1,000 | 216.0 |
| Building stone and flagstone | 1.80 | 3,591 | 60.2 |
Source: ProGreen Services, read November 2026. Building stone and flagstone are listed there as 15 cubic feet per ton, which is 133 pounds per cubic foot. The coverage column is 108 square feet per cubic yard at 3 inches, divided by the tons per cubic yard.
Veneer or Full-Depth Stone
Full veneer is the thick type, typically 3 to 5 inches deep, and it averages 35 to 40 square feet per ton. Thin veneer is typically 3/4 to 1 1/2 inches deep. Halquist Stone does not give a per-ton figure for thin veneer, so the calculator asks for yours.
| Type | Typical depth | Coverage per ton |
|---|---|---|
| Full veneer | 3 to 5 in | 35 to 40 sq ft |
| Thin veneer | 3/4 to 1 1/2 in | Not stated. Ask your supplier. |
Halquist Stone gives thin veneer as an average of 3,000 square feet per truck, which is a load figure and not a per-ton figure. Stone for a retaining wall is a different job. Use the retaining wall calculator for wall units and base.
Common Stone Ordering Mistakes
The usual errors are using one density for every stone, mixing up inches and feet, and forgetting the extra. Each one moves the order by a full load, so check them before you call the supplier.
- Using one weight for all stone. Lava rock and marble differ by nearly three times.
- Entering depth in feet. The depth field is in inches, so 3 inches is 3, not 0.25.
- Ordering gravel by the stone figure. Gravel and crushed stone for a base belong in the gravel calculator.
- Skipping the extra. Curved edges and cuts leave offcuts.
- Forgetting openings on a veneer wall. Subtract windows and doors.
- Trusting a coverage number with no depth. Coverage per ton only means something at a stated depth.
Contractor's Note
Ask the supplier for the weight per cubic yard of the exact stone before you order. A delivery ticket shows tons, so compare your number with it. Then add the extra you chose for edges and cuts. Pair the stone with the polymeric sand calculator if you are setting it in joints.
Frequently Asked Questions
Sources and Review
Published November 2026. Last updated November 2026. Next review May 2027. This tool gives planning numbers, not a quote.
Reviews: project calculators · 31 calculators reviewed
Marcus Johnson is a Certified Construction Manager (CCM) with 20 years of experience in residential and commercial site work. He holds CCM certification from CMAA (member #2019-1247). He has managed NALP-member landscape installation projects covering more than 2 million square feet of site work. At CalcSummit, he writes all landscape volume and bulk-material calculators, applying field-tested coverage rates for mulch, gravel, sand, topsoil, and fill dirt.
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