🪨 Gravel Calculator

Enter your area and depth to find out exactly how much gravel, stone, sand, or topsoil you need — in cubic yards, tons, bags, and total cost.

Area & depth
ft
ft
in
Material
Price (optional)
$
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How to calculate how much gravel you need

The math is simple: volume = area × depth. Measure the length and width of your area, pick a depth, and multiply. This calculator does it for you and converts the result into the units suppliers actually use — cubic yards, tons, and 0.5 cubic foot bags — plus an estimated cost so you don't overspend at the yard.

The formula, step by step

1. Area = length × width (in feet) for a rectangle, or π × radius² for a circle.
2. Volume in cubic feet = area × (depth in inches ÷ 12).
3. Cubic yards = cubic feet ÷ 27 (suppliers sell bulk gravel by the yard).
4. Tons = cubic yards × material density (gravel is roughly 1.4 tons per yard).

How deep should gravel be?

For a walkable path, 2 inches is usually enough. For a driveway, aim for 4 inches over a compacted base — more if heavy vehicles use it. Decorative ground cover and drainage beds typically use 2–3 inches. Going deeper than you need is the most common way people waste money on gravel.

Material density reference

Material Approx. weight Common use
🪨 Pea Gravel~1.3 tons/yd³Paths, patios
🧱 Crushed Stone~1.4 tons/yd³Driveways, base
⚪ River Rock~1.4 tons/yd³Drainage, decor
🏖️ Sand~1.35 tons/yd³Paver base, fill
🟤 Topsoil~1.1 tons/yd³Gardens, lawns
🍂 Mulch~0.5 tons/yd³Garden beds

Bagged vs. bulk gravel

Bagged gravel (sold in 0.5 cubic foot bags) is convenient for small jobs but costs much more per cubic yard. As a rough rule, once you need more than about 10–15 bags, ordering bulk delivery by the cubic yard or ton is cheaper. Always add about 5–10% extra to cover compaction and uneven ground.