Outdoor Material Calculators
Outdoor jobs fail on volume. Concrete is bought in cubic yards or 60/80 lb bags, gravel by the ton, mulch by the yard — and each has a different unit. These calculators convert your area and depth into the units your supplier actually sells.
Concrete: yards for slabs, bags for small jobs
A slab or footing is a volume: (length × width × depth) ÷ 27 gives cubic yards. For a pour that big you'll order ready-mix by the yard. For fence posts, sonotubes and small pads, bags are easier: a 50 lb bag ≈ 0.375 cu ft, a 60 lb ≈ 0.45, an 80 lb ≈ 0.60. The concrete calculator gives you both — yards for the truck, bags for the wheelbarrow — and rounds up so you never run short mid-pour.
Gravel & mulch: volume to tons or yards
Gravel is sold by the ton, so multiply your volume by density — crushed stone runs roughly 1.4–1.6 tons per cubic yard. Mulch is sold by the cubic yard (or 2 cu ft bag), so convert area × depth into yards. Both are "square feet × depth" problems in disguise; get the depth right and the quantity is trivial.
Pavers & sod: count or coverage
Pavers are counted: divide the patio area by one paver's area, add 5–10% for cuts. Sod is coverage: divide by a pallet's square footage (often ~450 sq ft). Both need a base layer — paver sand and a compacted gravel base — so pair these with the gravel calculator.
Fence & deck: spacing drives the count
Fences are built on spacing, not area: posts ~8 ft on center, pickets at a set width plus gap. Decks are area plus ~10% waste converted to boards. If you're setting posts in concrete or building a wood structure, chain the concrete and lumber calculators in — outdoor projects almost always need two or three of these tools together.