How the gravel calculator works
The unit tower, climbed
Area × depth = cubic feet; ÷ 27 = cubic yards; × stone weight (1.3–1.6 tons/yd) = tons. Quarries sell by the ton, landscapers quote by the yard, trucks deliver by the bucket — the calculator speaks all three because quotes arrive in all three. The compaction factor (+15–20%) is the conversion everyone forgets until the finished layer reads half-depth.
Stone types beyond color
Pea gravel (rounded, ~1.3 t/yd) walks comfortably and rolls underfoot — bad for driveways. Crushed 3/4" (~1.4) locks into itself — the universal driveway and drainage stone. Crusher run / dense grade (~1.5) includes fines that compact hard — the base-layer champion. Sand and screenings (~1.6) level pavers but never build structure. Weight varies because density does — the tonnage math tracks the type.
Delivery logistics
A ton is roughly one front-loader scoop; dump trucks carry 10–20 tons. Delivery minimums (often 2–3 tons) and per-load fees dominate small orders — which is why bagged stone from the box store wins under ~half a ton and loses beyond it. Order a pile with margins: spreading always finds another spot that "could use a little more."