Gravel Calculator: How Much Gravel for a Patio Base

Updated 2026-07-28 · Yardly

For a typical patio, plan on 4 inches of compacted gravel under the sand and pavers — which works out to about 1.25 cubic yards per 100 square feet compacted, or roughly 1.5 cubic yards ordered once you account for compaction. Here’s the math, and the two details that decide whether your base lasts.

The gravel formula

Gravel is sold by the cubic yard (or the ton), but you measure your patio in feet and the base depth in inches. The conversion is the same volume math behind every Yardly calculator:

(Length × Width × Depth ÷ 12) ÷ 27 = cubic yards

For a 12×14 ft patio at 4 inches deep: 168 sq ft × 0.333 ft = 56 cubic feet, divided by 27 = about 2.1 cubic yards compacted. The gravel calculator does this instantly and switches between yards and tons.

Two adjustments turn that raw number into an order:

• Extend the footprint. The base should run about 6 inches past the paver edge on every open side, so add a foot to each dimension before you multiply.
• Add a compaction margin. Crushed stone loses roughly 15–20% of its loose volume under a plate compactor. Order 1.2× your compacted volume, or you’ll come up an inch short after tamping.

So that 12×14 patio really means a 13×15 footprint → 2.4 cubic yards compacted → about 3 cubic yards ordered (roughly 4.2 tons at 1.4 tons per yard).

Order the right stone, not just the right amount

The best base material is dense-graded crushed stone — commonly sold as road base, crusher run, or Class II base. It mixes angular chunks with fines, so it locks into a nearly solid layer when compacted.

What it is not: pea gravel, river rock, or decorative stone. Rounded gravel behaves like a box of marbles no matter how long you run the compactor — pavers set over it rock and settle within a season or two. Guidance from the Interlocking Concrete Pavement Institute specifies well-graded angular aggregate for exactly this reason.

Depth depends on the job

• Patios and walkways (foot traffic only): 4 inches compacted minimum; go to 6 inches over clay soil or in freeze-thaw climates.
• Driveways or anything a vehicle touches: 8–12 inches — a different project entirely.
• Soft or wet subgrade: add depth and consider a geotextile separation fabric under the stone so soil fines can’t migrate up into the base.

When in doubt, deeper is cheap insurance: the base is the one layer you can’t fix without pulling up the whole patio.

Compact in lifts, not all at once

A plate compactor only densifies the top few inches of stone per pass. Spread the gravel in 2–4 inch lifts and compact each one before adding the next. Dumping the full depth and compacting once leaves the bottom loose — and a loose bottom consolidates later, taking your paver surface down with it.

After the base, you’ll screed about 1 inch of bedding sand — the sand calculator covers that layer — and then set the pavers themselves, which the paver calculator counts from the same dimensions.

Keep reading

• Planning the whole slab-to-surface stack? The paver patio project estimator totals gravel, sand, and pavers from one set of dimensions.
• How to estimate pavers for a patio walks the surface-layer math step by step.
• Comparing loose-stone surfaces instead? Start with the gravel calculator and price both by the yard.

Frequently asked questions