Gravel Calculator — Cubic Yards, Tons and Cost 2026

Gravel Calculator Formula — How It Works

The gravel calculator above — also called a rock calculator, crushed stone calculator, aggregate calculator, or gravel estimator — handles all the maths automatically. For manual calculation or to check the result, here is the exact formula:

Worked example — how much gravel for a driveway: A 20 × 10 foot driveway at 4 inches deep with #57 crushed stone. Area = 200 sq ft. Cubic yards = 200 × 4 ÷ 324 = 2.47 yd³. Tons = 2.47 × 1.4 = 3.46 tons. With 15% overage = 2.84 yd³ and 3.98 tons. Order 3 cubic yards or 4 tons and confirm with your supplier.

For circular areas such as tree rings: Area = π × (diameter ÷ 2)² — enter this directly into the circle calculator above. For triangular corner beds: Area = 0.5 × base × height. For irregular L-shapes: split into two rectangles, calculate each, add the results. The irregular shape option in the calculator above handles this automatically.

Gravel Density by Material Type

The gravel calculator uses density to convert cubic yards to tons. Density varies significantly by material — using the wrong density leads to under-ordering. The table below uses data from USGS aggregate research cross-referenced with supplier specifications.

Lava rock is the significant outlier — at 0.75 tons per cubic yard it is roughly half the weight of other gravel types because it is volcanic and porous. You need substantially more cubic yards of lava rock per ton compared to any other material. Always confirm density with your specific supplier — moisture content and grade variation affect the actual weight delivered.

Coverage Table — How Much Area Does Gravel Cover?

Use this table to quickly estimate gravel coverage before opening the calculator. Figures use standard crushed stone at 1.4 tons per cubic yard and include no waste buffer.

Add 10 to 15 percent to all figures before ordering. Gravel compacts after installation — particularly crushed stone and crusher run which compact by 20 to 30 percent. Order a little extra rather than running short mid-project.

Depth Guide by Project Type

Pre-Calculated Quantities for Common Project Sizes

These figures use standard crushed stone at 1.4 tons per cubic yard and include a 10 percent waste buffer.

Gravel Size Guide — Which Type for Which Project

Gravel is classified by size using ASTM D448 standard designations. The number refers to a sieve size classification — smaller numbers are larger stones. Understanding the size designations prevents ordering the wrong material for your project.

The most important distinction for driveway projects: angular stone (crushed) versus rounded stone (pea gravel, river rock). Angular stones interlock when compacted and provide structural stability. Rounded stones cannot interlock regardless of compaction effort. Every driveway needs angular base material. The surface layer can be decorative pea gravel on top. Using pea gravel as the only driveway material creates ruts within weeks. See the driveway guide for the full layered specification.

French Drain Gravel Calculator

French drains use a different calculation method than surface gravel. The trench has specific dimensions and the gravel fills around a perforated pipe — not just covering a flat area.

Standard residential French drain specifications:

French drain gravel rule — always use #57 angular crushed stone. Pea gravel should not be used in load-bearing French drains. Rounded pea gravel migrates into the perforated pipe over time, blocking the holes and eventually defeating the entire drainage system. Angular #57 stone maintains the void structure under load and keeps the pipe clear. For a decorative surface drain with no structural pipe, pea gravel is acceptable. See the sizes guide for the full French drain specification.

Dump Truck Load Calculator

For large projects, gravel arrives by dump truck. Knowing truck capacities helps you estimate the number of loads and plan for deliveries.

To calculate the number of trucks needed: divide your required tons by the truck capacity. Always round up — never order a partial load for cost reasons. Full truckloads cost 15 to 25 percent less per ton than partial deliveries because the supplier charges the same delivery fee regardless of load size.

Most residential suppliers use tandem-axle trucks for standard delivery. Confirm truck type when ordering — tri-axle trucks are heavier and may damage soft or unpaved driveway surfaces. If your existing driveway is soft or has recently been graded, specify a tandem-axle truck to reduce ground pressure.

Bulk vs Bags — Break-Even Calculation

The break-even point is approximately 3 cubic yards. Below this, bags are often more practical — no minimum order, no delivery scheduling, available immediately at Home Depot or Lowe's. Above 3 cubic yards, bulk delivery almost always saves money even after the delivery fee. Above 5 cubic yards, the savings are substantial and bulk is the clear choice. Use the cost calculator to compare at your specific supplier prices.

Gravel Cost — 2026 Prices

Prices vary significantly by region and season. The Southeast and Midwest typically have the lowest crushed stone prices due to abundant local quarries. The Pacific Coast tends to run 15 to 25 percent higher. Spring and early summer are peak season — ordering in late autumn or winter can reduce material cost by 10 to 20 percent at many suppliers.

For exact project cost at your local supplier price, use the cost calculator. For pea gravel specifically, the 2026 cost guide covers regional prices, bulk vs bag break-even, and seasonal buying windows in detail.

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