Pea Gravel Calculator
Pea gravel sells by the cubic yard or by the bag, but your project is measured in square feet and depth. This calculator bridges that gap -- converting your coverage area into cubic yards, tons, bags, and total cost for your walkway, patio, garden bed, or drainage project.
Quick Reference
Pea Gravel Compared
Pea gravel is a versatile, low-maintenance material. Here is how it compares to other landscaping options:
| Type | Weight (lbs/ft³) | Tons/Yard³ | Best For | Typical Price/yd³ |
|---|---|---|---|---|
| Pea Gravel | 100 | 1.35 | Walkways, gardens, drainage | $30-$55 |
| Lava Rock | 50 | 0.68 | Decorative, mulch replacement | $40-$70 |
| Crushed Gravel | 105 | 1.42 | Driveways, road base | $25-$45 |
| River Rock | 110 | 1.49 | Borders, water features | $35-$65 |
| Decomposed Granite | 105 | 1.42 | Paths, patios, ground cover | $40-$60 |
Pea Gravel Depth Guide
Depth depends on your project. Too thin and it will not provide adequate coverage. Too deep and you waste money.
| Depth | Best For | Sq Ft per Ton |
|---|---|---|
| 2 inches | Walkways, garden beds, ground cover | ~135 sq ft |
| 3 inches | Patios, decorative areas | ~90 sq ft |
| 4 inches | Drainage, French drains | ~68 sq ft |
| 6 inches | Playgrounds, deep drainage | ~45 sq ft |
How to Use This Calculator
Step 1: Choose your area shape - Rectangle for standard areas, Circle for tree wells or round features, or Total Area if you already know the square footage.
Step 2: Enter dimensions. For rectangle, enter length and width. For circle, enter diameter. For total area, enter square footage directly.
Step 3: Set depth using the preset buttons (2"-6") or enter a custom value.
Step 4: Enter pricing. The calculator shows bulk vs bag cost comparison.
Step 5: Results show instantly - tons, cubic yards, bag count, cost breakdown, and total.
Pea Gravel Formula
The calculator converts your project dimensions into pea gravel volume and cost:
- Rectangle: Area = Length x Width
- Circle: Area = Pi x (Diameter / 2)²
- Volume (ft³) = Area (ft²) x (Depth in inches / 12)
- Volume (yd³) = Volume (ft³) / 27
- Tons = Volume (ft³) x 100 lb/ft³ / 2,000
- Bags (0.5 cu ft) = Volume (ft³) / 0.5
- Bulk Cost = Volume (yd³) x Price per Cubic Yard
- Bag Cost = Bags x Price per Bag
Pea gravel has a consistent density of 100 lbs per cubic foot (2,700 lbs per cubic yard). Coverage per ton varies by depth: 135 sq ft at 2", 90 sq ft at 3", and 68 sq ft at 4".
Worked Example: 12x4 Walkway
Let us calculate pea gravel for a 12 ft x 4 ft walkway at 3 inches deep with 10% waste.
Step 1: Calculate volume:
Volume = 48 x (3 / 12) = 12 ft³
Cubic Yards = 12 / 27 = 0.44 yd³
Step 2: Calculate weight:
Tons = 1,200 / 2,000 = 0.60 tons
Step 3: Calculate cost at $42/yd³:
Bags = 12 / 0.5 = 24 bags x $5 = $120
Total: 0.44 cubic yards of pea gravel at $18.48 bulk vs $120 bagged. Use the calculator above to model your own project.
Tips and Common Mistakes
Best Practices
- Use landscape fabric - Prevents weeds and keeps gravel from mixing with soil.
- Order 10% extra - Gravel settles and shifts; extra covers uneven spots.
- Edging is essential - Use metal, plastic, or stone edging to contain gravel.
- Compact in layers - For deep fills, compact in 2-3 inch lifts.
- Compare bulk vs bags - Bulk is almost always cheaper for projects over 1 cubic yard.
Avoid This
- Skipping landscape fabric: Weeds will grow through and gravel will sink into soil.
- Too thin a layer: Less than 2 inches will not provide adequate coverage.
- No edging: Gravel will spread into lawn and garden areas over time.
- Ordering too little: Running out mid-project means a second delivery fee.
- Ignoring drainage: Pea gravel drains well, but ensure proper grading underneath.
Frequently Asked Questions
A 0.5 cubic foot bag of pea gravel covers about 3 square feet at 2 inches deep. For 1 cubic yard (27 cubic feet), you need about 54 bags. For smaller projects, calculate cubic feet needed and divide by 0.5.
Pea gravel costs $30-$55 per cubic yard in 2026 when bought in bulk. Bagged pea gravel costs $4-$6 per 0.5 cubic foot bag, which works out to $216-$324 per cubic yard.
Pea gravel weighs about 2,700 lbs per cubic yard (100 lbs per cubic foot). One ton of pea gravel covers approximately 135 sq ft at 2 inches deep, 90 sq ft at 3 inches, or 68 sq ft at 4 inches.
Walkways need 2-3 inches of pea gravel for comfortable walking. For high-traffic areas, use 3 inches. Place landscape fabric underneath to prevent weeds and keep gravel from sinking into the soil.
Yes, landscape fabric is strongly recommended. It prevents weeds from growing through, keeps gravel from mixing with soil, and maintains a clean appearance. Overlap seams by 6-12 inches for best results.
Pea gravel is excellent for drainage. Its round shape creates natural channels for water flow. Use 4 inches deep in French drains, around foundations, or in low spots that collect water.