Pea Gravel Calculators

Which Pea Gravel Calculator Do You Need?

The right calculator depends on what question you're trying to answer. Most people start with one of two questions: how much pea gravel do I need, or how much will it cost. If your question is about quantity — cubic yards, cubic feet, tons, or bag count — use the coverage calculator. If your question is about budget, use the cost calculator after you have your volume figure.

For project-specific calculations, the driveway calculator and patio calculator go deeper than the general coverage calculator. The driveway version automatically adds the recommended 4-inch minimum depth and a 15% compaction factor — because pea gravel settles under vehicle weight and you need to order more than the bare volume to end up with the right depth. The patio version supports circular and irregular shapes, which the standard length × width formula can't handle accurately.

How All Pea Gravel Calculations Work

Every calculator on this site uses the same core formula:

From this base volume, the calculators derive everything else. Weight is calculated by multiplying cubic yards by the material density — 1.35 tons per cubic yard for pea gravel based on USGS aggregate data. Bag count divides the cubic yard figure by the volume per bag (0.5 cubic feet, or approximately 0.0185 cubic yards, per standard 50-lb bag). Cost multiplies the cubic yard figure by your entered price per unit.

All calculators include a 10% waste factor by default. This accounts for irregular edges, material lost during spreading, and the natural settling that occurs after installation. For driveways, an additional 15% compaction factor is applied on top of the waste factor — gravel under vehicle traffic compacts significantly more than gravel on a decorative patio.

Pea Gravel Calculator vs General Gravel Calculator

The calculators on this page are calibrated specifically for pea gravel — rounded, water-worn stone typically in the 3/8-inch size range. The weight calculations use pea gravel's specific density of approximately 100 lb per cubic foot (1.35 tons per cubic yard). If you're working with crushed stone, river rock, decomposed granite, or other materials, the volume formula is the same but the weight output will differ because material densities vary:

Bulk vs Bagged Pea Gravel — When Each Makes Sense

The bags calculator shows both the bag count and the crossover point where bulk delivery becomes the cheaper option. As a general rule, bulk delivery from a landscape supplier wins economically for any project above 1.5 cubic yards — approximately a 10×15 ft patio at 3 inches deep.

Below that threshold, bags from a home improvement store are competitive on price and far more convenient — no minimum delivery order, no scheduling a truck, and you can buy exactly what you need. The trade-off is physical labour: 1 cubic yard requires approximately 54 standard 50-lb bags. For a 2-cubic-yard project that's 108 bags to carry, open, and empty. Most people find the convenience advantage of bags disappears quickly above half a cubic yard.

For a detailed comparison including 2026 regional price ranges, see the pea gravel cost guide.

Recommended Depths by Application

The depth you enter into any of these calculators has the biggest impact on your final quantity. Use the wrong depth and you'll either run short within a season or over-order significantly. These are the verified recommended depths used as defaults across all calculators on this site:

Coming Soon — More Calculators

The following calculators are currently in development and will be added to this page as they are verified and published:

• General gravel calculator — covers crushed stone, river rock, decomposed granite, road base, and lava rock with material-specific density values
• Pea gravel path calculator — optimised for narrow walkway dimensions with edging loss factor
• Dog run calculator — includes drainage depth recommendations and area sizing
• Playground gravel calculator — ASTM F1292 compliant, 9–12 inch depth standard
• Cubic yards to tons converter — quick reference converter for all gravel types
• Mulch calculator — same formula, different density values for organic mulch materials
• Topsoil calculator — for raised beds and ground-level garden applications

These pages are listed in order of build priority. If you need a specific calculator that isn't listed, contact us and it will be moved up the build schedule.

How to Get an Accurate Result

Three things determine the accuracy of any pea gravel calculation: the area measurement, the depth choice, and the density figure used. The calculators handle density automatically using verified USGS data. Your job is to provide accurate dimensions and choose the right depth for your application.

For rectangular areas, measure the longest length and widest width at the actual ground level — not what you plan the final area to be after edging is installed. For irregular areas, divide the space into two or more rectangles, calculate each separately, and add the results. For circular areas, measure the diameter and use π × (diameter ÷ 2)² to calculate the area in square feet before entering it into the coverage calculator.

Always add a 10% buffer to your final order for waste and settling. The calculators include this automatically, but if you've already reduced the figure for some reason, add it back before placing your order. Running short on a bulk delivery and ordering a second load is significantly more expensive per unit than ordering the right quantity the first time.

For more detail on the formulas behind these calculators, see the methodology page. For installation depth guidance beyond the table above, the installation guide covers base preparation, edging, landscape fabric, and compaction for each project type.

Not sure which calculator to use?

Start with the coverage calculator — it handles most projects and gives you cubic yards, tons, and bag count in one step.

Open Coverage Calculator →