Gravel Calculator

How to Calculate Gravel for a Project?

Multiply the length by the width by the depth (all in feet) to get cubic feet. Divide by 27 to convert to cubic yards. Multiply the cubic yards by the gravel density (in pounds per cubic yard) and divide by 2,000 to get US tons. A gravel driveway 50 feet long, 12 feet wide, and 4 inches deep needs 50 x 12 x 0.333 = 200 cubic feet = 7.41 cubic yards. At 2,700 pounds per cubic yard, that weighs roughly 10 tons. The calculator above handles these conversions automatically and adjusts the weight based on the gravel type you select.

What Types of Gravel Are Available?

Crushed stone is angular, interlocks when compacted, and makes the best base for driveways and foundations. It weighs about 2,800 pounds per cubic yard. Pea gravel consists of small, rounded stones (3/8-inch diameter) used for walkways, drainage beds, and decorative groundcover. It weighs about 2,500 pounds per cubic yard. River rock is larger rounded stone (1-3 inches) used for landscaping, dry creek beds, and erosion control at 2,600 pounds per cubic yard. Decomposed granite is finely crushed granite that packs firm and drains well, popular for pathways at 2,400 pounds per cubic yard. Lava rock is lightweight volcanic stone used as decorative mulch at 2,200 pounds per cubic yard.

How Deep Should Gravel Be for Different Uses?

Driveway base: 4-6 inches of crushed stone, compacted in two lifts. Patio or shed base: 4 inches of compacted crushed stone. Walkway or garden path: 2-3 inches of pea gravel or decomposed granite. Landscaping ground cover: 2-3 inches of decorative rock. French drain backfill: 8-12 inches of washed gravel surrounding the perforated pipe. Under concrete slabs: 4-6 inches of compacted gravel as a subbase. Each additional inch of depth across a large area adds significant volume and weight. Doubling the depth from 2 to 4 inches doubles the cubic yards and cost, so specifying the correct depth matters for your budget.

How Much Does Gravel Cost?

Crushed stone and standard gravel cost $30-$60 per cubic yard or $15-$30 per ton from a landscape supply yard. Pea gravel runs $35-$55 per ton. River rock costs $50-$100 per ton depending on size and color. Decomposed granite is $25-$50 per ton. Delivery charges add $50-$150 per truckload depending on distance. A standard dump truck holds 10-14 cubic yards. For small quantities under 1 cubic yard, bagged gravel from home centers is convenient but expensive (roughly $4-$6 per 50-pound bag, which works out to $160-$240 per ton). Bulk delivery is dramatically cheaper for any project over 2 cubic yards.

How to Calculate Gravel by Weight vs Volume?

Suppliers sell gravel by the ton in some regions and by the cubic yard in others. Converting between the two requires knowing the material density. Divide the weight per cubic yard by 2,000 to get tons per cubic yard: standard gravel at 2,700 lbs/yd3 equals 1.35 tons per cubic yard. Multiply your cubic yards by this factor. When a supplier quotes by the ton, divide your calculated tons by the tons-per-cubic-yard figure to verify the volume makes sense. The calculator shows both cubic yards and tons so you can order confidently regardless of how the supplier prices their material.

Do I Need to Compact Gravel?

Any gravel base supporting a structure, vehicle traffic, or another material layer must be compacted. A plate compactor handles areas up to 6 inches deep. A vibratory roller works for larger areas and thicker lifts. Compact in lifts no thicker than 4 inches at a time for best results. Wet the gravel slightly before compacting to help the angular particles lock together. Rounded materials like pea gravel and river rock do not compact as tightly as angular crushed stone because the smooth surfaces slide past each other. For base applications requiring maximum stability, always use angular crushed stone rather than rounded gravel.

Gravel for Drainage Applications

Washed gravel (free of fine particles) is essential for drainage applications because the open spaces between stones allow water to flow freely. Standard gravel with fines (dust and small particles) packs tightly and restricts water flow, defeating the purpose of a drainage bed. French drains use 3/4-inch washed stone surrounding a perforated pipe. Dry wells use larger 1-2 inch washed stone to maximize void space for water storage. Rain garden underdrains use a gravel layer beneath the planting soil to collect and filter stormwater. For any drainage application, specify "washed" or "clean" gravel when ordering to ensure the fines have been removed.

How Many Dump Truck Loads Do I Need?

A standard tandem-axle dump truck holds 10-14 cubic yards or 12-16 tons, depending on the truck size and material weight. A single-axle truck holds 5-8 cubic yards. A pickup truck with a standard bed holds about 0.5 cubic yards of gravel (roughly 1,400 pounds), which approaches the payload limit for most half-ton trucks. For a 10-cubic-yard order, one full tandem truck makes a single trip. For 25 cubic yards, expect two full loads and one partial. Coordinating multiple loads on the same day reduces delivery charges and ensures you can spread and compact each load while the material is freshly dumped and easy to work with.

Frequently asked questions