Gravel Calculator

How to use the gravel calculator

Measure the area in feet at its longest and widest points. For paths and curved runs, treat each straight-ish stretch as its own rectangle, run the calculator per section, and add the results — a 40 ft winding path that averages 3 ft wide is just 40 × 3. Round up to the nearest half foot; gravel is forgiving and the truck doesn’t deliver in teaspoons.

Depth depends on the job. Two to three inches suits decorative ground cover and weed-suppression layers over fabric. Three inches is the standard for walkways. Driveways and parking pads need more total stone — typically four to six inches or deeper, built in two-to-three-inch compacted lifts, so calculate each lift separately or set the depth to the full build-up and accept a single-pour estimate.

The coverage-type select matters more than it looks. "Loose fill" is gravel that stays roughly the volume you pour: decorative rock, French-drain fill, mulch-style top layers. "Compacted base" adds 15% because stone packed with a plate compactor consolidates — the same hole swallows more material than its open volume suggests. Any layer that will carry weight (paver base, driveway base, shed pad) should be calculated as compacted.

The Advanced density setting converts volume to weight, because bulk suppliers quote and sell by the ton as often as by the yard. The 1.4 tons-per-cubic-yard default fits common pea gravel and mixed crushed stone; crushed limestone and granite run 1.4–1.5, and damp coarse sand pushes 1.5. When the quarry’s site lists a density for your specific product, use theirs.

Order the cubic-yard number for delivery, and have a plan for the pile: a yard of gravel weighs around 2,800 lb, so the driveway spot you choose is where it stays until you move it a wheelbarrow at a time. For weed-prone areas, lay landscape fabric first — it keeps the stone from migrating into the soil and roughly doubles the life of the layer.

The formula

Volume math with a compaction factor, then a density conversion to tons — the same takeoff a quarry dispatcher runs over the phone:

cubic feet = length × width × (depth ÷ 12) × compaction factor   [1.0 loose, 1.15 compacted]
cubic yards = cubic feet ÷ 27
tons = cubic yards × density   [1.4 tons/yd³ default]

Worked example with the defaults: a 10 × 10 ft area at 3 inches, loose fill, is 10 × 10 × 0.25 = 25 cubic feet — 0.93 cubic yards. At 1.4 tons per cubic yard that’s about 1.3 tons. Switch to compacted base and the same hole takes 28.75 cubic feet ≈ 1.06 yards ≈ 1.5 tons.

Suppliers sell in half-yard or half-ton increments; round up to the next increment they offer. Slightly long beats a second delivery fee every time.

Frequently asked questions