Introduction
Figuring out how much pea gravel you need for a project can be tricky. Buy too little and you'll make extra trips to the supply yard. Buy too much and you'll waste money on material you don't need. This pea gravel calculator takes the guesswork out of your project by giving you exact amounts in cubic yards, tons, and even the number of bags required.
Simply enter the shape and size of your area — rectangular, circular, or triangular — along with your desired depth. The calculator handles the rest, including adjustments for compaction and waste that many people forget to account for. It also provides a full cost breakdown with material prices, delivery fees, and tax so you can budget your project from start to finish. Whether you're covering a garden path, filling a patio, building a drainage bed, or laying a driveway base, this tool helps you order the right amount of pea gravel the first time.
How to Use Our Pea Gravel Calculator
Enter the shape and size of your area, the gravel depth you need, and your pricing details. The calculator will tell you how much pea gravel to buy in cubic yards, tons, and bags, along with the total cost.
Shape: Pick the shape of your area — rectangular, circular, or triangular. This tells the calculator how to figure out your coverage area. If you need help determining your area dimensions, our square footage calculator can assist with that step.
Length and Width (Rectangular): Enter the length and width of your space. You can choose feet, inches, yards, meters, or centimeters for each measurement.
Diameter or Radius (Circular): Enter the diameter of your round area. You can also type in the radius instead. The calculator will sync the other value for you.
Base and Height (Triangular): Enter the base and height of your triangle-shaped area. Pick the unit that matches your measurements.
Depth: Choose how deep you want your pea gravel. Use the quick-select buttons for common depths or type in a custom number. A good rule of thumb is 1–2 inches for decorative use, 2–3 inches for walkways, 3–4 inches for driveways, and 4–6 inches for heavy traffic areas.
Pea Gravel Size: Select the size of pea gravel you plan to use, from 1/8 inch up to 3/4 inch. The standard size is 3/8 inch.
Material Type: Choose from standard pea gravel, river rock, crushed stone, or decorative stone to match your project. If you're considering river rock instead, try our dedicated river rock calculator for more precise estimates on that material.
Compaction Factor: Check this box to add 15% extra material. Gravel settles and compacts over time, so this helps make sure you order enough.
Waste Allowance: Select a waste percentage to account for spills and uneven spreading. A 10% allowance is the default and works well for most projects.
Density: Enter the weight of your pea gravel in pounds per cubic foot. The default of 90 lb/ft³ is typical for most pea gravel, but you can adjust it if your supplier provides a different number.
Price per Ton: Enter how much your supplier charges per ton of pea gravel. The calculator compares this with the per-yard price and uses whichever saves you more money.
Price per Cubic Yard: Enter the cost per cubic yard if your supplier prices gravel that way. This gives you a second pricing option.
Delivery Fee: Enter the flat delivery charge from your supplier. This gets added to your material cost before tax.
Tax Rate: Enter your local sales tax percentage. The calculator applies this to the subtotal to give you an accurate final cost.
Pea Gravel Calculator: How Much Pea Gravel Do You Need?
Pea gravel is a small, rounded stone typically between 1/8 inch and 3/4 inch in size. It gets its name because the stones are about the size of a pea. Unlike crushed stone, which has sharp edges, pea gravel has smooth, rounded surfaces because it has been naturally worn down by water over time. It comes in a mix of earthy colors including tan, brown, white, and gray, making it a popular choice for many outdoor projects.
Common Uses for Pea Gravel
Pea gravel is one of the most versatile landscaping and construction materials available. Homeowners and builders use it for walkways, patios, driveways, garden beds, drainage solutions, and as a decorative ground cover. It drains water well, which makes it a great option for areas that tend to collect standing water. Many people also use it around fire pits, between stepping stones, and as a base layer under pavers. For larger aggregate projects like erosion control, a rip rap calculator can help you estimate heavier stone needs.
How to Figure Out How Much You Need
To calculate the right amount of pea gravel, you need three measurements: the length and width (or diameter for circular areas) of your space, plus the depth you want to fill. Multiply these together to get the volume. The formula for a rectangular area is simple: Length × Width × Depth = Volume. For a circle, use π × radius² × depth. Volume is usually measured in cubic feet or cubic yards, and since there are 27 cubic feet in one cubic yard, you divide your cubic feet total by 27 to get cubic yards.
Recommended Depth by Project Type
The depth of pea gravel you need depends on how the area will be used. For decorative purposes like garden borders, 1 to 2 inches is enough. Walkways work best with 2 to 3 inches of gravel. Driveways need 3 to 4 inches to hold up under the weight of vehicles. Areas with heavy foot or vehicle traffic should have 4 to 6 inches. Going too thin means the gravel will shift and expose the ground underneath. Going too thick wastes money without adding real benefit.
Weight and Density
Pea gravel weighs about 90 pounds per cubic foot, or roughly 1.35 tons per cubic yard. This weight can vary slightly depending on how wet the gravel is and the exact type of stone. Knowing the weight matters when you are figuring out delivery costs, choosing a vehicle to haul it, or deciding how many trips you will need to make. A standard half-ton pickup truck can safely carry about half a ton (1,000 pounds), which is less than one cubic yard of pea gravel.
Why You Should Add Extra for Compaction and Waste
Loose pea gravel settles and compacts over time, especially after rain or foot traffic. Most professionals recommend adding 10 to 15 percent extra material to account for compaction. You should also plan for some waste during spreading and transport. A 10 percent waste allowance is standard for most projects. Without these adjustments, you may end up with thin spots that need to be filled later, costing you more in the long run.
Buying Pea Gravel: Bags vs. Bulk
For small projects, pea gravel is sold in bags, usually 0.5 cubic feet each. Bagged gravel is convenient but costs more per cubic foot. For larger areas, buying in bulk by the cubic yard or by the ton is much cheaper. Most landscape supply yards sell bulk pea gravel for around $30 to $60 per ton or $40 to $80 per cubic yard, depending on your location and the type of stone. Delivery fees typically range from $50 to $150 based on distance and load size.
Tips for a Successful Pea Gravel Project
- Use edging: Pea gravel spreads easily, so install metal, plastic, or stone edging to keep it in place. If you're building a border with blocks, our retaining wall calculator can help you estimate materials.
- Lay landscape fabric: Place weed barrier fabric under the gravel to prevent weeds from growing through.
- Compact the base: If you are building a walkway or patio, compact the soil underneath before adding gravel for a more stable surface. For projects that require a sand or dirt base layer, calculate those materials separately.
- Order a little extra: It is always better to have a small amount left over than to run short and pay for a second delivery.
- Consider adjacent materials: If your project also involves concrete footings, mulch borders, or topsoil for surrounding garden beds, plan those quantities at the same time to coordinate a single delivery when possible.