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Pea Gravel Calculator

Measure each area in feet, set your depth (the cited range is below), and get pea gravel in cubic yards, an estimated tonnage range, and bag counts. The volume is exact geometry; the tonnage is honestly a range — and the page shows you why.

Areas to cover (measure in feet; add one entry per section)
Depth (cited range below the calculator)

Enter at least one area and a depth to see how much pea gravel to order.

How this is calculated

Formula v1.0 · Data v2026.3, verified 2026-07-31

  1. Shape areas are summed and multiplied by depth:volume = total area × depth (at depth d inches,cubic yards = square feet × d ÷ 324).
  2. Tonnage = volume × conversion factor, shown as a range at1.5–1.7 tons per cubic yard — the Wisconsin DOT statewide factor for the coarse sand / sand-and-gravel aggregate class, compacted in place. We could not find a pea-gravel-specific producer figure worth citing, so we show the class range and say so, rather than inventing precision.
  3. Bags = ⌈volume ÷ bag size⌉, using the size printed on the bag.

Data used, with sources

ValueUsed asSource
Tonnage conversion 1.5–1.7 tons/cu yd (compacted)tonnage shown as a range — WisDOT statewide conversion factor for the coarse sand / sand-and-gravel aggregate class, compacted in place — not a pea-gravel-specific producer figure. Quarry conversions vary; your supplier’s scale ticket governs.Wisconsin Department of Transportation / Wisconsin Highway Research Program
Depth: landscape bed / rock mulch cover2–4 in, preset 3 inUtah State University Extension; Colorado State University Extension

Why the tonnage is a range

Pea gravel is sold both by the cubic yard and by the ton, and every quarry converts between the two with its own factor — stone type, moisture, and gradation all move the number. Calculators that print a single tons-per-yard figure are hiding that spread, not resolving it. If your supplier sells by the ton, ask for their conversion; if you can order by volume, do — the cubic-yard figure above involves no conversion at all.

Choosing a depth

For beds and ground cover, extension guidance runs2–4 inches: Utah State Extension puts inorganic mulch at 2–3 inches; Colorado State Extension uses 4 inches where weed suppression is the goal and notes a 3-inch gravel layer sharply improves water infiltration — with the explicit warning that more is not better. For stones to function as mulch at all, Colorado State advises keeping them under half an inch in diameter — which is what pea gravel is.

Frequently asked questions

How much does a cubic yard of pea gravel weigh?
There is no single honest number — quarry conversions vary with stone type and moisture. The cited engineering figure for the sand-and-gravel aggregate class is 1.5–1.7 tons (3,000–3,400 lb) per cubic yard, compacted in place; loose delivered material runs lighter. Your supplier's scale ticket governs.
How deep should pea gravel be?
For landscape beds and rock mulch, university extension guidance runs 2 to 4 inches: Utah State Extension recommends 2–3 inches for inorganic mulch, and Colorado State Extension calls for 4 inches where weed suppression is the goal — while warning that more is not better. Stones should be under half an inch in diameter to work as mulch.
How many square feet does a ton of pea gravel cover?
At a 3-inch depth, one cubic yard covers 108 square feet, so a ton covers roughly 64–72 square feet using the 1.5–1.7 tons-per-cubic-yard class conversion. Order by volume when you can — it skips the conversion entirely.
Is pea gravel a good mulch?
In dry climates, yes — Colorado State Extension reports that gravel smaller than one centimeter suppresses weeds and reduces evaporation comparably to wood chips, improves water infiltration (pea gravel especially, in short intense storms), and is the best mulch option for fire-resistant landscaping.

Sources

Quantities on this page are planning estimates, not engineering advice or a purchase guarantee — product sizes vary by producer, so confirm coverage with your supplier before ordering.