Gravel Calculator

Volume = area × depth, then multiply by the density for tonnage. A 20 × 10 ft area (200 sq ft / 19 m²) at 2 in deep is about 1.2 yd³ (0.95 m³); at roughly 1.4 US tons per cubic yard (1.6 t/m³) for crushed stone that is about 1.7 US tons (1.5 t) — order around 1.9 US tons (1.7 t) with a 10% settling allowance. The calculator handles the unit conversions and the allowance.

Around 1.5–2 in (40–50 mm) for decorative ground cover and paths (deep enough to hide the ground, shallow enough to walk on), and 3–4 in (75–100 mm) for driveways — ideally in two compacted layers over a proper sub-base. Too shallow shows bald patches; too deep is hard to walk on and wastes stone.

About 1.3–1.4 US tons per cubic yard (1.5–1.7 t/m³) for most crushed stone and river pebbles — the calculator defaults to 1.4 US tons/yd³ (1.6 t/m³) and lets you adjust it. Lighter materials differ: decomposed granite runs about 1.2 US tons/yd³ (1.4 t/m³), and bark mulch only about 0.25 (0.3), which is why buying by volume or weight matters by material.

A weed barrier (geotextile) under decorative gravel keeps soil and stone separate and stops the gravel disappearing into the ground within a season — it typically saves a full re-top within a few years. Driveways need a compacted sub-base; the gravel is the wearing surface, not the structure.

Above roughly half a cubic yard (m³), bulk (loose or bulk-bag) delivery is much cheaper per ton than small bags. A standard bulk bag holds about 1 cubic yard (0.7–0.9 m³) depending on the stone. Small 50 lb (40 kg) bags suit top-ups and hard-to-reach spots.