Pea Gravel Calculator
Work out how much pea gravel to order for a path, patio, fire-pit circle, dog run or play area. Enter the shape and size, pick a depth, and get cubic yards, tons and bags. The example is a round fire-pit patio 16 ft across, 3 in deep.
Safety: Surfacing under play equipment should follow the CPSC Public Playground Safety Handbook and the equipment maker's fall-height guidance; this calculator only estimates volume.
How to use the pea gravel calculator
- Choose the shape: Circle for a fire-pit area or tree ring (enter the full diameter), Rectangle for paths and patios, Triangle for corners. Use Add another area for each extra piece.
- Set the depth from the table below: about 2 in for paths, 3 in for patios, 4 in for a dog run, 12 in under play equipment.
- Leave Pea gravel selected under Material; its density (1.4 tons per yd³) is filled in. Change it if your supplier gives a different weight.
- Read cubic yards (for bulk by volume), tons (for bulk by weight) and 0.5 ft³ bags. Enter prices under Cost estimate to compare.
How much pea gravel do I need?
Pea gravel is worked out like any loose material: area × depth gives volume, and density turns volume into weight.
- Area: length × width for a rectangle, π × (diameter ÷ 2)² for a circle
- Volume (ft³) = area × depth (in) ÷ 12 × (1 + waste)
- Cubic yards = ft³ ÷ 27
- Tons = yd³ × 1.4 (typical for pea gravel)
- Bags = ft³ ÷ 0.5, rounded up
Stone Center lists pea gravel at 1.4–1.6 tons per cubic yard. Pea gravel isn't compacted, so the compaction allowance stays at 0%.
Worked example: a 16 ft round fire-pit patio, 3 in deep
This is the circle loaded above.
- Area: π × 8² = 201.06 ft².
- Volume: 201.06 × 3 ÷ 12 = 50.3 ft³. Add 10%: 55.29 ft³.
- Cubic yards: 55.29 ÷ 27 = 2.05 yd³.
- Weight: 2.05 × 1.4 = 2.87 tons.
- Bags: 55.29 ÷ 0.5 = 110.6, rounded up to 111 bags of 0.5 ft³.
Over a hundred 50 lb bags is nearly 3 tons of lifting, so a bulk delivery is the obvious choice here. Most landscape yards sell pea gravel by the ton or by the cubic yard; the calculator gives both so you can compare quotes.
Pea gravel depth by use
Pea gravel is small (about ⅜ in), smooth and rounded, which makes it comfortable underfoot and good-looking, but it doesn't lock together like crushed stone. That decides how deep to lay it:
- Paths and stepping-stone infill: about 2 in. Deeper than that and it feels like walking on a beach.
- Patios and seating areas: about 3 in, over a compacted base and landscape fabric.
- Dog runs: 3–4 in, so it drains and can be raked clean.
- Under play equipment: the U.S. CPSC lists pea gravel as a non-impact-tested loose fill that needs 12 in installed (compressing to 9 in) to protect against falls of up to 5 ft. It also notes that loose fill compresses by at least 25% with use.
Pea gravel depth by use: yards, tons and bags per 100 ft²
| Use | Depth | yd³ per 100 ft² | Tons per 100 ft² | 0.5 ft³ bags per 100 ft² | Area 1 ton covers |
|---|---|---|---|---|---|
| Garden path, stepping-stone infill | 2 in | 0.62 | 0.86 | 34 | 116 ft² |
| Patio, fire-pit or seating area | 3 in | 0.93 | 1.3 | 50 | 77 ft² |
| Dog run | 4 in | 1.23 | 1.73 | 67 | 58 ft² |
| Under play equipment (CPSC, protects to 5 ft) | 12 in | 3.7 | 5.19 | 200 | 19 ft² |
Pea gravel at 1.4 tons per yd³, no waste. The play-area depth is the CPSC's initial fill for non-impact-tested pea gravel (12 in, compressing to 9 in). Path and patio depths are common practice, not a code figure.
Pea gravel tips
- Use solid edging. Rounded stones roll and migrate into the lawn. Steel, aluminum, stone or paver edging set slightly above the gravel keeps it in place.
- Put a base under patios. A few inches of compacted crushed stone (see the gravel calculator) under the pea gravel stops it sinking into the soil and makes the surface firmer.
- Landscape fabric helps. Fabric between soil and gravel slows weeds and keeps the stones from mixing into the dirt.
- Not for driveways or slopes. Pea gravel rolls under tires and washes down slopes. Use angular crushed stone there: see the driveway gravel calculator.
- Rake it level after delivery. A delivered pile is never spread evenly; rake to the depth you planned and top up the low spots.
Frequently asked questions
How much does a yard of pea gravel weigh?
About 1.4 tons (2,800 lb) per cubic yard, and up to about 1.6 tons depending on the stone and moisture (Stone Center). Ask your supplier for their figure and enter it under Density.
How much area does a ton of pea gravel cover?
At 1.4 tons per yd³, one ton covers about 116 ft² at 2 in deep or 77 ft² at 3 in.
How deep should pea gravel be?
About 2 in for paths, 3 in for patios and 3–4 in for dog runs. Under play equipment, the CPSC table calls for 12 in installed (9 in compressed) to protect falls of up to 5 ft.
How many bags of pea gravel make a yard?
A cubic yard is 27 ft³, so it takes 54 bags of 0.5 ft³ (about 50 lb each).
Is pea gravel safe for playgrounds?
It can be used, but the CPSC classes it as a non-impact-tested material: you need 12 in installed (9 in once compressed) for falls up to 5 ft, kept topped up. For higher equipment, use a tested surfacing material.
More gravel calculators
Related calculators
- Paver CalculatorPavers for a patio or path, plus gravel base, bedding sand and edging length.
- Mulch CalculatorCubic yards and bags of mulch for one or several beds, at the depth you choose.
- Topsoil CalculatorCubic yards, tons and 40 lb bags of topsoil for lawns, beds and low spots.
- Paver Base CalculatorGravel base and bedding sand for a patio, walk or driveway, by use.