Stop Guessing at the Supply Yard
Order too little pea gravel and you pay for a second delivery — or stall your project for a weekend. Order too much and a leftover pile sits on your driveway for years. Gravel suppliers sell by the cubic yard or the ton, so the only way to order right is to convert your patio, path, or garden bed into those units first.
This free pea gravel calculator does exactly that. Enter your length, width, and depth, and it returns cubic yards, cubic feet, tons, and how many standard 0.5-cubic-foot bags you would need — plus an estimated cost if you enter your supplier’s price per ton. It handles rectangles and circles, and it adds a waste allowance (default 10%) so the number you order matches what actually gets spread.
Estimated cost
| Step | Volume | Weight |
|---|---|---|
| Base volume (exact fit) | – | – |
| Waste allowance (–) | – | – |
| Order quantity | – | – |
Weight uses the standard pea gravel density of about 1.4 tons per cubic yard (roughly 105 lb per cubic foot). Actual density varies by quarry and moisture, so confirm with your supplier before placing a large order. Bag counts round up to whole bags.
How to Use This Calculator
- Pick your shape. Choose Rectangle for most patios and paths, or Circle for round beds and fire-pit areas — the calculator switches the inputs for you.
- Enter your measurements. Type the length and width (or diameter) in feet and the depth in inches. Measure the actual area you will cover, not the whole yard.
- Set the waste allowance. It starts at 10%, the industry standard for compaction, spillage, and uneven ground. Raise it for irregular shapes.
- Add a price per ton (optional). If your supplier quoted a bulk price, enter it to see an instant cost estimate.
- Click Calculate Pea Gravel. The headline number is what to order with waste included; below it you get cubic feet, tons, bag count, and a step-by-step breakdown.
What Is Pea Gravel?
Pea gravel is naturally rounded stone weathered to roughly the size of a pea — most pieces fall between 1/8 and 3/8 inch. It comes in warm tans, grays, whites, and rust tones, and its smooth, rounded shape is what separates it from crushed stone, whose angular faces lock together under pressure.
That rounded shape is both the appeal and the trade-off. Pea gravel feels good underfoot, drains beautifully, and looks soft in beds and borders — which is why it is a favorite for patios, garden paths, playgrounds, fire-pit surrounds, and decorative top-dressing. But the same roundness means the stones roll instead of locking, so pea gravel migrates without edging and is a poor choice for steep slopes or driveways, where angular crushed stone performs better.
The Formula
Tons = cubic yards × 1.4 • Bags = cubic feet ÷ 0.5 (rounded up)
Shortcut for rectangles: (L × W × depth in inches) ÷ 324 = cubic yards
Worked example. A 12 ft × 8 ft patio at 3 inches deep:
- Area = 12 × 8 = 96 sq ft
- Depth in feet = 3 ÷ 12 = 0.25 ft
- Volume = 96 × 0.25 = 24 cubic feet
- Cubic yards = 24 ÷ 27 ≈ 0.89 yd³
- Add 10% waste: 0.89 × 1.1 ≈ 0.98 yd³ to order
- Weight = 0.98 × 1.4 ≈ 1.37 tons
- Bags = 26.4 ft³ ÷ 0.5 = 52.8 → 53 bags
The calculator above runs this same sequence automatically, for rectangles and circles alike.
How Deep Should Pea Gravel Be?
Depth is the variable that changes your order most — one extra inch on a large patio can add half a cubic yard. This is also where most people undershoot: a thin layer looks fine on day one, then foot traffic exposes the base within weeks.
| Project | Depth | Notes |
|---|---|---|
| Decorative garden beds | 1–2 in | Top-dressing only; suppresses weeds without smothering plant crowns |
| Garden paths and walkways | 2–3 in | Comfortable to walk on; firm edging keeps it in place |
| Patios and seating areas | 2–3 in | Lay over a compacted base; furniture sits most stably near 2–2.5 in |
| Play areas | 3–4 in | Check your equipment manufacturer’s safety specs |
| French drains | Full trench depth | Rounded stones let water move freely through the voids |
| Driveways | 4–6 in over road base | Caution: rounded stone shifts under tires — crushed angular stone is usually the better pick |
For anything people walk on, 2 to 3 inches is the sweet spot. Less looks patchy fast; more starts to feel unstable, especially under chairs and tables.
Tips for a Clean, Long-Lasting Install
- Lay landscape fabric first. A woven geotextile stops weeds from below and keeps gravel from sinking into the soil. Overlap the seams by a few inches.
- Install edging before you spread. Metal, plastic, or brick edging keeps rounded pea gravel contained and out of the lawn. It is the single biggest factor in how long the install looks good.
- Ask for washed pea gravel. Unwashed stone carries dust that dulls the color and slows drainage; washed gravel looks cleaner from day one.
- Get 2–3 local quotes. Bulk gravel pricing varies widely by region and quarry. Call local supply yards, ask for the price per ton delivered, and order a sample bag — color looks different in person.
- Choose bulk delivery or bags by project size. Bulk delivery wins on price for anything around a cubic yard or more. Bags make sense for small top-ups and spots a dump truck cannot reach.
- Spread, rake, and mist. Dump in piles, rake level to your target depth, then mist lightly with a hose — it settles the dust and beds the stones together.
Pea Gravel Coverage Chart: Yards, Tons, and Bags by Depth
At this calculator’s density (1.4 tons per cubic yard, about 2,800 lb), coverage per unit works out to:
| Depth | 1 cubic yard covers | 1 ton covers |
|---|---|---|
| 1 inch | 324 sq ft | 231 sq ft |
| 2 inches | 162 sq ft | 116 sq ft |
| 3 inches | 108 sq ft | 77 sq ft |
| 4 inches | 81 sq ft | 58 sq ft |
In bags, one cubic yard is 54 of the standard 0.5 cu ft bags, and one ton is about 40 bags — the point where most people stop loading bags into a cart and phone the landscape yard instead. However you buy it, firm edging is not optional with pea gravel: the rounded stones roll and migrate underfoot, and a border is what keeps your patio’s gravel on the patio.
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Frequently Asked Questions
How do I calculate how much pea gravel I need?
Multiply length × width (feet) × depth (feet) to get cubic feet, then divide by 27 for cubic yards, and add about 10% for waste. A shortcut for rectangles: (length × width × depth in inches) ÷ 324 = cubic yards.
How many tons of pea gravel are in a cubic yard?
About 1.4 tons (roughly 2,800 pounds) at the standard density of around 105 pounds per cubic foot. Real density varies by quarry, stone size, and moisture, so confirm with your supplier before placing a large order.
How many bags of pea gravel will I need?
Divide your total cubic feet by the bag size and round up. With standard 0.5-cubic-foot bags, a project needing 26.4 cubic feet requires 53 bags. The calculator above does this rounding for you.
How deep should pea gravel be for a patio or path?
Two to three inches is the standard for patios, paths, and seating areas. One to two inches works for decorative top-dressing, while play areas usually need three to four inches.
Should I put landscape fabric under pea gravel?
Yes. A woven geotextile fabric prevents weeds and stops the gravel from sinking into the soil over time. Install it before the edging and gravel, overlapping seams by a few inches.
Is it cheaper to buy pea gravel in bags or in bulk?
Bulk delivery is almost always cheaper per ton once a project reaches about one cubic yard — one cubic yard equals roughly 54 standard bags. Bags make sense for small top-ups and areas a delivery truck cannot reach.
How much does pea gravel cost?
Bulk prices vary widely by region; most US suppliers price it per ton with a delivery fee on top. Call two or three local quarries or landscape supply yards for exact quotes, then enter the price per ton in the calculator above for an instant estimate.
Can I use pea gravel on a slope or driveway?
It is not recommended for slopes above about a 5% grade — the rounded stones roll and migrate with foot traffic and rain. The same shifting happens under tires, so angular crushed stone is generally the better choice for driveways.
How much pea gravel do I need for a 10×10 patio?
A 10×10 patio is 100 sq ft. At the recommended 3-inch depth: 100 × 3 ÷ 324 = 0.93 cubic yards. At 1.4 tons per yard that is about 1.3 tons, or 25 cubic feet ÷ 0.5 = 50 standard bags. Add 10% for settling and spillage and order about 1 full yard in bulk.
Does pea gravel need edging?
Yes. Pea gravel stones are rounded river rock, so they roll and travel under foot traffic instead of locking together like crushed stone. Install firm edging — metal, stone, or timber — around every pea gravel area, over landscape fabric, or the surface gradually thins out and spills into lawns and beds.
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