Figuring out how much landscape rock to buy comes down to two numbers: the area you are covering and how deep you want the rock. Measure length times width for square footage, pick a depth, then convert that volume to tons or cubic yards. Plan on about 2 inches for decorative cover and 3 to 4 inches for paths and base work. This works for nearly any rock, which is why it is the starting point for sizing any job. Once you know the number, you can shop landscape rock by size and color and order the exact amount.
Step one: measure the area
Multiply length by width in feet to get square footage. A rectangle is straightforward. For an L shape or a curved bed, split it into rectangles, measure each, and add the pieces together. Round up rather than down so you are not short.
Step two: pick a depth for the job
Depth is where landscape rock projects differ, and it has the biggest effect on how much you order.
- Decorative cover (about 2 inches): beds, borders, and ground cover where you mainly want the look and to suppress weeds. Two inches hides the soil without burying plants.
- Paths and walkways (about 3 inches): a walking surface needs more material so it does not thin out and show dirt underfoot.
- Driveway base and heavy use (3 to 4 inches): anywhere vehicles drive or you need a stable base, go deeper so the rock holds up.
Step three: convert to tons or yards
Most landscape rock and gravel is sold by the ton; mulch and soil are usually sold by the cubic yard. The quick rule for rock is that one ton covers roughly 70 to 100 square feet at 2 inches, with bigger stone toward the low end and smaller, tighter-packing material toward the high end. If you would rather think in volume, one cubic yard covers about 150 square feet at 2 inches and about 100 at 3 inches. For the full breakdown of when to use each unit, see our guide on cubic yards vs tons.
Whichever unit you use, add about 5 to 10 percent for waste, settling, and topping off.
A worked example
Picture a backyard path, 20 feet long and 3 feet wide, that you want at 3 inches deep.
- Area: 20 times 3 equals 60 square feet.
- Depth: 3 inches for a walking surface.
- Coverage: at 3 inches, figure roughly 50 to 65 square feet per ton, so 60 divided by about 55 is a little over 1 ton.
- Waste: add 5 to 10 percent, so plan on about 1.2 tons.
Those are planning numbers. The coverage calculator takes your exact area and depth and returns the precise quantity in the right unit, so you do not have to estimate the per-ton coverage yourself.
Coverage by rock size
Stone size changes coverage more than most people expect. Large stone leaves big voids between pieces, so a ton does not go as far. Small, tight-packing material fills those voids and stretches further. Use this table to pick the coverage figure that matches the material you are actually buying.
| Material | Typical size | Coverage per ton at 2 inches |
|---|---|---|
| Landscape gravel | 3/8 inch to 3/4 inch | ~100 sq ft |
| Pea gravel | 3/8 inch, rounded | ~100 sq ft |
| Landscape rock | 3/4 inch to 1-1/2 inch | ~85 sq ft |
| River rock | 1 inch to 3 inch, rounded | ~75 sq ft |
| Rip rap and cobble | 3 inch to 12 inch | ~55 sq ft |
| Boulders | 12 inch and up | sized by the piece, not by area |
Boulders are the exception to the whole method. You do not cover an area with them, you place them individually, so you size a boulder order by count and weight rather than by square footage. Our guide on how to choose boulders for landscaping covers that separately.
Choosing the rock
The size and type of rock you pick affects coverage, so it is worth settling on a material before you finalize the amount. Each group below matches a row of the table above.
Landscape rock and gravel, about 85 to 100 sq ft per ton
California Gold Granite Gravel
Navajo Granite Gravel
Thunderstorm Grey Granite
Salt N Pepper Gravel
Ruby Red Granite Gravel
Del Rio Pea Gravel
River rock, about 75 sq ft per ton
Rip rap and cobble, about 55 sq ft per ton
Boulders, sized by the piece
If you are shopping by look rather than by size, white landscape rock, black landscape rock, and lava rock narrow the field fast. Decomposed granite is its own case with its own math; our guide on how much decomposed granite do I need covers it in detail.
If you are still deciding on a material rather than a quantity, start with our guide to landscape rock types or landscape rock sizes explained, then come back here to size the order.
Sizing other materials
Every material has its own coverage rate and its own selling unit. If your project uses more than rock, these guides run the same math for each one:
- How much river rock do I need
- How much decomposed granite do I need
- How much flagstone do I need
- How much sand do I need
- How much bark mulch do I need
- Cubic yards vs tons
Ordering the quantity you calculated
Once you have a tonnage, the next question is how it arrives. Small jobs work by the bag or the half yard; anything past a few tons is a bulk load and the delivery method changes. Our bulk landscape rock delivery guide covers load sizes and access requirements, and how landscape rock is delivered walks through what happens on the day. Order a little over your calculated figure rather than a little under. A second delivery for half a ton costs far more than the extra material would have.
Every material above ships as a 16oz or 32oz sample. Ordering one before a bulk load is the cheapest way to avoid the most expensive mistake, which is tons of the wrong colour.
Frequently asked questions
How do I calculate how much landscape rock I need?
Measure length times width for square footage, pick a depth, and convert to tons or cubic yards. As a rough guide, one ton covers about 70 to 100 square feet at 2 inches. Add 5 to 10 percent for waste.
How deep should landscape rock be?
About 2 inches for decorative beds and ground cover, around 3 inches for paths, and 3 to 4 inches for driveway base or heavy-use areas. Deeper layers hold up better under foot and vehicle traffic.
Is landscape rock sold by the ton or the cubic yard?
Most rock and gravel is sold by the ton because it is dense and heavy. Mulch and soil are usually sold by the cubic yard. For most rock, figure roughly 1.3 to 1.5 tons per cubic yard.
How much area does a ton of landscape rock cover?
Roughly 70 to 100 square feet at 2 inches deep, depending on stone size. Larger stone leaves more gaps and covers less area; smaller, tighter material covers more.
How many tons is a cubic yard of landscape rock?
A cubic yard of landscape rock weighs about 2,800 pounds, which is roughly 1.4 tons. River rock runs a little heavier at about 2,900 pounds per yard, and gravel and decomposed granite a little lighter at about 2,700. Bark mulch is the outlier at roughly 700 pounds per yard.
How much landscape rock do I need for 500 square feet?
At 2 inches deep, 500 square feet takes about 5 to 7 tons of typical landscape rock, or roughly 3 cubic yards. At 3 inches it is closer to 8 to 10 tons. Add 5 to 10 percent on top for waste and settling.
What size landscape rock covers the most area?
Smaller, tighter-packing material covers the most per ton. Pea gravel and 3/8 inch gravel get close to 100 square feet per ton at 2 inches, while 1 to 3 inch river rock covers about 75 and rip rap around 55, because larger stone leaves bigger voids.
How much extra should I order?
Add about 5 to 10 percent over your calculated amount to allow for waste, settling, and topping off. Running the numbers through the coverage calculator gives you an exact figure to start from.
Get the materials
Browse landscape rock and landscape gravel, then run your dimensions through the coverage calculator for an exact quantity. For bulk loads or long-distance delivery, request a quote and we will work out freight. We deliver nationwide from our California yards.