Pea Gravel Calculator
Find how many tons, cubic yards, or bags of pea gravel a patio, path, or drainage bed needs - for rectangular, round, or triangular areas.
Your Pea Gravel Estimate
- Pick a shape - rectangle, round (enter diameter for a circular bed), or triangle.
- Enter area - dimensions, a known square footage, or a known volume - plus quantity for several same-size areas.
- Set depth - 2" for decorative cover, 3" for paths, 4" for patios, 6" for drainage.
- Check density - 96 lb/ft³ is standard - pea gravel is lighter than crushed stone.
- Add price (optional) - enter price per ton for an estimated cost, and see the bag count for bagged purchases.
- Install edging first - pea gravel migrates without borders - set edging before filling.
Pea gravel sells two ways - bagged at the home center or in bulk by the ton - so it helps to know your number in both. The math: area in square feet × (depth ÷ 12) gives cubic feet; divide by 27 for cubic yards, multiply by 96 lb/ft³ for pounds, or divide by 0.5 for the number of standard bags. A ton covers about 100 sq ft at 2 inches; a single 0.5-cubic-foot bag covers roughly 3 sq ft at that depth. So a 10 × 10 ft patio at 2 inches comes to about 0.9 tons, or 37 bags - which is exactly why bulk wins past a small area.
Planning a Pea Gravel Project
Pea gravel consists of small, naturally rounded stones - typically about 3/8 inch (the #8/#9 size range) - that are smooth and comfortable underfoot. That makes it popular for patios, paths, dog runs, playgrounds, and decorative ground cover, and it drains better than most crushed stone.
One thing separates a pea gravel project that lasts from one that scatters across the lawn by summer: containment. The rounded stones don't lock together, so they wander without a hard edge. Set steel, plastic, or stone borders before you fill, expect to rake now and then, and you're most of the way there. Buy it bagged (0.5 ft³ bags) for a small bed or in bulk by the ton for a patio - the calculator gives you both numbers.
How Pea Gravel Is Installed
Three Pea Gravel Projects, Measured
These three cover the shapes people actually lay pea gravel in - a square patio, a round fire-pit ring, a triangular bed. Each shows the bag count too, since that's how most pea gravel gets bought.
1. 10 × 10 patio (rectangle). 100 sq ft at 2 in deep, 10% waste. Volume = 100 × (2 ÷ 12) = 16.7 cu ft, plus 10% = 18.3 cu ft. That is about 0.68 cubic yards, roughly 0.9 tons, or about 37 of the 0.5 cu ft bags. A 12 × 12 patio at 2 in works out to about 1.3 tons (around 53 bags).
2. Round fire-pit border (circle). 12 ft diameter, 3 in deep, 10% waste. Area = π × (12 ÷ 2)² = 113 sq ft. Volume = 113 × (3 ÷ 12) = 28.3 cu ft, plus 10% = 31.1 cu ft - about 1.15 cubic yards or 1.5 tons. Pick the round shape and enter the diameter.
3. Triangular garden bed (triangle). 14 ft base, 18 ft height, 2 in deep, 10% waste. Area = (14 × 18) ÷ 2 = 126 sq ft. Volume = 126 × (2 ÷ 12) = 21 cu ft, plus 10% = 23.1 cu ft - about 0.86 cubic yards or 1.1 tons. Use the triangle shape and enter base and height.
After You Estimate Pea Gravel
A pea gravel surface is only as good as what's under it. Before or alongside ordering the stone:
How Deep Should Pea Gravel Be?
Pea Gravel Coverage by Area and Depth
| Area | Depth 2" | Depth 3" | Depth 4" |
|---|---|---|---|
| 50 ft² | 0.31 yd³ (0.4 tons) | 0.46 yd³ (0.6 tons) | 0.62 yd³ (0.8 tons) |
| 100 ft² (10×10) | 0.62 yd³ (0.8 tons) | 0.93 yd³ (1.2 tons) | 1.23 yd³ (1.6 tons) |
| 144 ft² (12×12) | 0.89 yd³ (1.2 tons) | 1.33 yd³ (1.7 tons) | 1.78 yd³ (2.3 tons) |
| 200 ft² | 1.23 yd³ (1.6 tons) | 1.85 yd³ (2.4 tons) | 2.47 yd³ (3.2 tons) |
| 500 ft² | 3.09 yd³ (4.0 tons) | 4.63 yd³ (6.0 tons) | 6.17 yd³ (7.9 tons) |
Based on 96 lb/ft³ density. These are base quantities before waste - add about 10% when ordering. One ton of pea gravel covers about 100 sq ft at 2 inches deep.
Bags vs. Bulk, and the 3/8" Size
Pea gravel is sold two ways. Home centers like Home Depot and Lowe's stock it in bags - usually 0.5 cubic feet, which weigh around 40-50 lb and cover about 3 sq ft at 2 inches deep. Landscape supply yards sell it in bulk by the ton or cubic yard, which is far cheaper per unit once you need more than about a ton. As a rule of thumb, bags make sense for small touch-ups and tight access; bulk wins for any real patio or path. The calculator shows both the bulk tonnage and the bag count so you can compare.
Most pea gravel sold in the US is the 3/8-inch size - small, rounded stones in the #8 to #9 gradation range under ASTM D448. Some suppliers also carry a slightly larger 1/2-inch decorative grade. The 3/8-inch size is the comfortable, walkable one used for patios and paths; confirm the size with your supplier, since color and stone shape vary by region.
Formulas
Volume-to-weight with pea gravel density:
Area - circle = π × (Diameter ÷ 2)²
Area - triangle = (Base × Height) ÷ 2
Volume (ft³) = Area × (Depth ÷ 12)
Cubic yards = Volume ÷ 27
Weight (tons) = Volume × 96 ÷ 2,000
Bags (0.5 ft³) = Volume ÷ 0.5
With waste = Results × (1 + Waste %)
Pea gravel is lighter than crushed stone - one cubic yard weighs about 1.30 tons versus 1.89 tons for crushed #57 limestone.
Sizing & Material Standards
- Pea gravel size falls in the #8 to #9 range of ASTM D448, the standard that defines aggregate size numbers by sieve gradation. The common "3/8 inch" label corresponds to these small, rounded gradations.ASTM D448 - Standard Sizes of Aggregate
- Where pea gravel is used as fine aggregate in concrete or mortar, the cleanliness and grading requirements are set by ASTM C33.ASTM C33 - Concrete Aggregates
Pea gravel cost by quantity (2026 US)
| Quantity | Cost bulk delivered | Coverage at 3 in deep | Notes |
|---|---|---|---|
| 1 ton | $35-$70 | ~70 sq ft | Small walkway or bed |
| 5 tons | $150-$300 | ~350 sq ft | Mid-size project |
| 10 tons | $280-$550 | ~700 sq ft | Large patio or driveway |
| Bag (0.5 cu ft) | $4-$8 per bag | ~2 sq ft at 3 in | Touch-ups, small fills |
| Northeast region | $45-$90 per ton | - | Highest - transport costs |
| Southeast and Midwest | $30-$55 per ton | - | Near national average |
Delivery ($50-$200) is usually charged separately for small orders. Colored pea gravel adds $20-$50/ton. Bags from home centers cost 3-5x more per cubic yard than bulk.
Related Calculators
Pea gravel works great over a compacted base. See the full landscaping calculator collection for all material tools.