Aggregate Calculator
Work out the cubic yards and tons of crushed stone or aggregate for an area at a chosen depth, with cost.
How it works
cubic yards = length × width × (depth ÷ 12) ÷ 27 · tons = cubic yards × density (≈1.4 t/cu yd for stone)
Aggregate is priced by weight but installed by volume, so both matter. Compute the volume as length by width by depth (depth converted from inches to feet), divide by 27 for cubic yards, then multiply by the material density to get tons. Crushed stone runs around 1.4 tons per cubic yard; lighter pea gravel is nearer 1.25. Because a base layer compacts as it is rolled and some material scatters, ordering about 10% extra keeps you from a second delivery.
Worked example
A 30 × 12 ft driveway base at 4 in: 30 × 12 × (4 ÷ 12) = 120 cu ft ÷ 27 = 4.44 cu yd. At 1.4 t/cu yd that is 6.2 tons, or about 6.8 tons with a 10% allowance.
Frequently asked questions
How many tons of gravel in a cubic yard?
Crushed stone and gravel average about 1.4 tons per cubic yard, but it varies with the rock and moisture. Pea gravel is lighter at roughly 1.25, and dense crusher run a touch heavier — use your supplier’s figure when you can.
How deep should a gravel base be?
Two to three inches suffices for a decorative or walkway layer, while a driveway base wants four inches or more of compacted crushed stone, often over a separately calculated sub-base. Deeper, well-compacted stone spreads vehicle loads and drains better.
Why order extra?
Crushed stone compacts noticeably when rolled, so a loose 4 in layer finishes thinner, and some always scatters off the edges. Ten percent extra covers compaction and spillage on most jobs.
Related calculators
Estimates only — add for waste and confirm against local building codes and supplier specs.