How the pea gravel calculator works
The math is the same as for any loose stone. The calculator:
- Works out the area in square feet (length × width, or 3.14 × radius² for a circle).
- Multiplies by depth in feet (inches ÷ 12) to get cubic feet.
- Divides by 27 to get cubic yards.
- Multiplies cubic yards by the weight of pea gravel, about 2,900 lb per cubic yard (1.45 tons), to get tons.
- Adds the waste allowance you set (10% by default).
Worked example. A 16 × 12 ft patio is 192 square feet. At 3 inches deep that is 192 × 0.25 = 48 cubic feet, or 1.78 cubic yards. With 10% extra you would order about 1.95 cubic yards, which is roughly 2.8 tons.
How deep to lay pea gravel
| Use | Pea gravel depth | Underneath |
|---|---|---|
| Decorative bed | 2 in | Landscape fabric |
| Garden path | 2–3 in | Fabric, plus 3–4 in of compacted crushed stone on soft ground |
| Patio or seating area | 3–4 in | 4 in of compacted crusher run or crushed stone |
| Dog run | 3–4 in | Compacted base so urine drains rather than pools |
| Play area | Far deeper than landscaping (see below) | Follow playground safety guidance |
Pea gravel rolls underfoot because the stones are round. On paths and patios, keep the top layer to 3 or 4 inches and use edging (steel, aluminum, stone or timber) so it stays put. Plastic honeycomb stabilizer grids also help on paths and parking areas.
Play areas. If pea gravel is the safety surface under a swing set or climber, use the depth given in the U.S. Consumer Product Safety Commission’s Public Playground Safety Handbook for your equipment’s fall height. Loose fill compacts over time, so the handbook asks for more at installation than the minimum depth it needs to keep.
Pea gravel coverage
At about 1.45 tons per cubic yard:
| Depth | Sq ft per cubic yard | Sq ft per ton |
|---|---|---|
| 1 inch | 324 | about 225 |
| 2 inches | 162 | about 112 |
| 3 inches | 108 | about 75 |
| 4 inches | 81 | about 56 |
Bags or bulk?
Pea gravel is sold in 0.5 cubic foot bags at most garden centers, and loose by the cubic yard or ton at landscape supply yards.
- Small jobs (under about 1 cubic yard): bags are easy to carry and you avoid a delivery fee. One cubic yard is 54 half-cubic-foot bags.
- Bigger jobs: bulk is almost always cheaper per cubic yard, even with delivery. A pickup truck can usually carry about half a cubic yard to one cubic yard safely; check your truck’s payload rating, because a cubic yard of pea gravel weighs close to 1.5 tons.
The bags of gravel calculator compares bag sizes, and the yards to tons converter helps when one supplier quotes by the yard and another by the ton.
Pea gravel sizes and colors
Most pea gravel is 1/4 to 3/8 inch. Some yards also sell a larger 1/2 inch grade, which shifts less underfoot. Color depends on the local stone: tan, white, grey, rose and mixed “river” tones are common. Washed pea gravel has had dust and fines rinsed off, so it drains better and stays cleaner on top.
Weights here are averages for dry, loose stone. Ask your supplier for their own weight per cubic yard if you are ordering by the ton.
Questions people ask
- How much pea gravel do I need?
- Multiply length × width × depth (in feet) to get cubic feet, divide by 27 for cubic yards, then multiply by about 1.45 for tons. A 16 × 12 ft patio at 3 inches needs about 1.8 cubic yards, or roughly 2.6 tons.
- How deep should pea gravel be?
- About 2 to 3 inches for paths and decorative areas, 3 to 4 inches for patios, and much deeper for play areas, where you should follow playground safety guidance rather than landscaping depths.
- How much does a cubic yard of pea gravel weigh?
- Roughly 2,800 to 3,000 pounds, or about 1.4 to 1.5 tons. Wet pea gravel is heavier.
- How many bags of pea gravel are in a cubic yard?
- 54 bags of 0.5 cubic feet. Most 0.5 cu ft bags weigh around 45 to 50 pounds.
- Does pea gravel need a base?
- For paths and patios, yes. A compacted layer of crushed stone or crusher run under the pea gravel stops it sinking into soil, and edging keeps it from spreading.