Gravel & Aggregate Calculator

A 10 by 20 foot area at 4 inches deep equals 10 x 20 x (4/12) = 66.7 cubic feet. Dividing by 27 gives approximately 2.5 cubic yards. Adding a 10 percent waste allowance brings the order to about 2.7 cubic yards. At roughly 1.4 tons per cubic yard, that is around 3.8 tons of material.

It depends on the material. Standard crushed gravel weighs approximately 1.4 tons per cubic yard. Pea gravel is lighter at about 1.3 tons per cubic yard. Sand is similar to gravel at roughly 1.35 tons. Wet or very dense angular crushed stone can reach 1.5 tons per cubic yard. Ask your supplier for the actual weight per yard if precision matters for your order.

A new gravel driveway should have a compacted base layer of 4 to 6 inches of larger crushed stone for drainage and stability, topped with 2 to 3 inches of smaller gravel as the driving surface. When topping up an existing gravel driveway, 2 to 3 inches of fresh material is typically sufficient. Using multiple compacted layers produces a much more stable surface than a single deep layer.

For the surface layer, 3/4-inch to 1-inch crushed stone or washed river gravel is popular because it compacts well and drains effectively. Pea gravel looks attractive but rolls and disperses underfoot and under tires. A base layer of 1.5 to 2-inch crusher run, which includes fines, compacts tightly and creates a stable foundation that prevents the surface gravel from sinking into soft soil.

Natural gravel has rounded edges worn smooth by water. Crushed stone is angular because it's broken up at a quarry. Angular material locks together better and forms a more stable base, ideal for driveways and paths. Rounded gravel looks better for decorative use.

Compaction, spreading over uneven edges, and actual depth running deeper than planned in low spots all eat into your order. Ordering 10-15% extra avoids paying for a second delivery, which usually costs more than the extra material itself.