Pea Gravel Calculator
Cubic yards, tons & bags of pea gravel
Spreading pea gravel for a patio, path or play area? Enter the area and depth to get the cubic yards, tons and 50 lb bags you need. Below: how deep to go for each use, a coverage chart, a worked patio, what it costs delivered versus bagged, and the jobs pea gravel is wrong for.
How deep should pea gravel be?
Depth is decided by what walks or sits on it, and going deeper is not always better — pea gravel is round, so a deep layer behaves like ball bearings underfoot.
| Use | Depth | Base underneath |
|---|---|---|
| Garden path, light foot traffic | 2 in | Fabric on firm soil |
| Patio or fire-pit area | 2 to 3 in | 2 to 4 in compacted crusher run |
| Play area under equipment | 3 to 4 in | Fabric, no hard base |
| Dog run | 3 in | Fabric on drained soil |
| Drainage trench or French drain | Fill depth | Fabric-wrapped trench |
| Driveway | Not recommended — see below | |
Past about 3 inches the stones simply roll under your feet, and a chair or table will sink. If you want a patio that feels solid, the answer is a compacted crusher-run base with 2 inches of pea gravel on top, not 5 inches of pea gravel.
Pea gravel coverage chart
Per 100 ft², including the 10% the calculator adds for settling into the base.
| Depth | Cubic yards | Tons | 50 lb bags |
|---|---|---|---|
| 1 in | 0.34 yd³ | 0.46 | 19 |
| 2 in | 0.68 yd³ | 0.92 | 37 |
| 3 in | 1.02 yd³ | 1.38 | 55 |
| 4 in | 1.36 yd³ | 1.83 | 74 |
| 6 in | 2.04 yd³ | 2.75 | 110 |
Turned the other way round, one ton of pea gravel covers about 120 ft² at 2 inches or 80 ft² at 3 inches, and one cubic yard covers 162 ft² at 2 inches. Used as a pea gravel calculator tons is the figure most bulk yards will quote you, since stone is sold by weight.
Worked example: a 12 × 16 ft gravel patio
A 12 by 16 ft patio is 192 ft² at a 3-inch finished depth, with the calculator's 10% overage:
| Item | Working | Order |
|---|---|---|
| Volume plus 10% | 192 × 0.25 ft × 1.1 | 1.96 yd³ |
| As weight | 1.96 × 1.35 | 2.64 tons |
| If bagged instead | 52.8 ft³ ÷ 0.5 | 106 × 50 lb bags |
| Landscape fabric | 192 ft² plus overlap | about 220 ft² |
| Edging | perimeter 56 ft | 60 ft plus spikes |
106 bags settles the bulk-versus-bagged question on its own. That is five or six trips in a car, roughly 5,300 lb of lifting, and it will cost two to three times what the same stone costs delivered loose.
Pea gravel cost
Enter your local price per ton in the price field to use this as a pea gravel cost calculator. For budgeting, these are the usual US ranges:
| How you buy it | Typical price | 192 ft² patio at 3 in |
|---|---|---|
| Bulk, per ton delivered | $35 to $75 | $92 to $198 |
| Bulk, per cubic yard | $45 to $95 | $88 to $186 |
| Bagged, 50 lb | $5 to $8 | $530 to $848 |
| Delivery fee | $50 to $150 | flat, per load |
Bags only make sense below about half a yard, roughly 25 bags. Above that the delivery fee is cheaper than your time, and coloured or washed decorative gravel sits at the top of these ranges or beyond.
Fabric, edging and what stops it spreading
Two things keep a pea gravel area looking deliberate rather than scattered:
- Landscape fabric underneath. It blocks weeds and, more importantly, stops the round stones migrating down into soft soil. Without it you lose visible depth every year and end up topping up.
- A hard edge all the way round. Steel, aluminium, paver or timber, set proud of the gravel. Rounded stone has no interlock at all, so any unrestrained edge migrates onto the lawn and into the mower.
Excavate to the full depth rather than mounding gravel on top of existing grade, so the finished surface sits flush with the lawn and stones are not constantly kicked out.
When to use crushed stone instead
Pea gravel is smooth, rounded and free-draining, which makes it comfortable underfoot and excellent around fire pits, along paths and in drainage trenches. Those same properties make it the wrong choice in three places:
- Driveways. Round stone will not lock together, so tyres rut it and push it aside within a season. Angular crushed stone is the correct material.
- Slopes. Anything past a gentle grade and it migrates downhill with every rainfall.
- Under pavers. A bedding layer must compact and hold; pea gravel never does. Use the paver base calculator for that job.
Pea gravel also does not compact, so it will not carry load. Anything that needs to bear weight wants a compacted base beneath it and pea gravel only as the visible surface.
How this pea gravel calculator works out its numbers
Volume is area × depth at 27 ft³ per cubic yard, with 10% added by default because rounded gravel settles into whatever is beneath it. Bag counts use a 50 lb bag yielding 0.5 ft³.
- Density is 100 lb/ft³, giving 1.35 tons per cubic yard. Real pea gravel runs 95 to 110 lb/ft³ depending on stone size, washing and moisture, so tonnage can vary about 10% either way.
- Depth guidance reflects common landscaping practice: shallow because rounded stone becomes unstable underfoot with depth, not because of cost.
- Coverage figures in the chart include the 10% overage, so they match what the calculator returns rather than the bare geometric volume.
- Cost ranges are US planning figures gathered September 2026 and vary widely by region, stone colour and haul distance.
Reviewed September 2026.
Figures reviewed . Every worked example on this page is checked against the calculator above.
Pea Gravel Calculator: frequently asked questions
How much area does a ton of pea gravel cover?
About 120 ft² at 2 inches deep, 80 ft² at 3 inches, or 60 ft² at 4 inches. One ton is roughly 0.74 cubic yards at pea gravel's typical 100 lb per cubic foot.
How much pea gravel do I need for a patio?
For a 12 × 16 ft patio at 3 inches deep, about 1.96 cubic yards or 2.64 tons including 10% for settling. In bags that would be 106 fifty-pound bags, which is firmly bulk-delivery territory.
How deep should pea gravel be?
2 inches for paths, 2 to 3 inches for patios over a compacted base, and 3 to 4 inches for play areas. Deeper than 3 inches feels unstable underfoot because the rounded stones roll rather than lock.
Do I need fabric under pea gravel?
Yes for almost every application. Landscape fabric blocks weeds and stops the stones sinking into soft soil, which is what causes an area to lose depth and need topping up every year.
Does pea gravel need edging?
Yes. The stones are rounded and have no interlock, so without a steel, paver or timber edge they migrate onto lawns and walkways continuously. Set the edge slightly proud of the finished gravel level.
Is pea gravel good for a driveway?
No. Round stone will not lock together under vehicle weight, so it ruts, scatters and needs constant raking. Use angular crushed stone or crusher run for driveways instead.
How much does pea gravel cost?
Roughly $35 to $75 a ton delivered in bulk, or $45 to $95 per cubic yard, plus a delivery fee of $50 to $150. Bagged at $5 to $8 per 50 lb bag it works out several times more expensive per yard.