The short version
Most decorative rock and gravel is sold by the ton. One ton covers about 100 square feet at 2 inches deep for 3/4" rock or smaller. For paths and beds, that's the number to start with. Bigger rock and deeper layers eat tonnage faster.
The math
The coverage shifts based on rock size and depth, but here's the working chart for DFW landscape rock:
| Material | Coverage at 2" deep | Coverage at 3" deep |
|---|---|---|
| Decomposed granite (DG, screened) | ~80 sq ft / ton | ~55 sq ft / ton |
| 3/8" pea gravel | ~100 sq ft / ton | ~67 sq ft / ton |
| 3/4" river rock | ~100 sq ft / ton | ~67 sq ft / ton |
| 1-2" river rock | ~70 sq ft / ton | ~47 sq ft / ton |
| 3-5" Texas river rock | ~50 sq ft / ton | ~33 sq ft / ton |
| Crushed limestone base | ~110 sq ft / ton | ~73 sq ft / ton |
Conversion if you'd rather think in cubic yards: 1 cu yd ≈ 1.4 tons for most landscape rock. A loose ton of 3/4" rock is about 0.7 cu yd.
Worked example. You're filling a 4 ft × 30 ft dry creek bed with 1-2" river rock at 3" deep. That's 120 sq ft. At 47 sq ft per ton:
120 ÷ 47 = 2.55 tons → order 3 tons
If you'd rather think in yards: 120 sq ft × 3" ÷ 324 = 1.11 cu yd × 1.4 = 1.56 tons. The difference between the two calcs is real — bigger river rock has more air gap than the table assumes, which is why we err toward the per-rock-size table above.
DG paths: 2 inches compacted is the sweet spot. For a 3 ft × 50 ft path = 150 sq ft × 2" = 300 cubic inches per sq ft. At ~80 sq ft per ton compacted, 2 tons. Wet, screed, and tamp it — DG that isn't compacted will rut the first time a wheelbarrow rolls across.
Common mistakes
- Using the cu-yd formula for big rock. The 324 divisor assumes a tight pack. For 3-5" Texas river rock there are basketball-sized air gaps. Use the tonnage table instead.
- Skipping landscape fabric under the rock. Bermuda will erupt through 4 inches of pea gravel in one growing season. Heavy woven fabric stapled down first, rock on top.
- Buying river rock for a path you'll walk barefoot. 1-2" river rock looks great around the AC unit; it's miserable to walk on barefoot. For paths, use DG or 3/8" pea gravel.
- Forgetting edging. Rock migrates. Steel edging, brick, or boulders to keep it contained or you'll be raking the driveway forever.
What to do next
The fastest math: rock & gravel calculator — pick the rock size, enter sq ft and depth, get tonnage. To see what's in the yard, shop rock & gravel or read the rock & gravel materials page for a walkthrough on size, color, and base requirements. If you're building a path specifically, the path/dry-creek wizard on that page sizes both the rock and the fabric for you.
Also useful
- How to size a French drain — uses 3/4" washed rock; same per-ton math
- How to size a gravel driveway — same materials, bigger scale, different base