Outdoor Living Calculator
Calculate how much gravel you need for a fire pit area. Estimate tons, cubic yards, bags, coverage, and cost for your backyard project.
Coverage per ton of gravel at your selected depth:
Choosing the right gravel size is crucial for both safety and aesthetics around your fire pit. Here's what works best for each application:
| Material | Recommended Size | Best Use |
|---|---|---|
| Pea Gravel | 1/8 – 1/4 inch | Seating surface — comfortable to walk on, provides natural drainage |
| River Rock | 1 – 3 inches | Decorative border — natural appearance, defines the fire pit perimeter |
| Crushed Stone | 3/4 inch | Base layer — excellent compaction for stability under the surface layer |
| Lava Rock | 1 – 2 inches | Fire-resistant decorative area — ideal for the zone closest to the fire pit |
The depth of gravel around your fire pit depends on the specific area and its purpose. Here are the standard recommendations:
| Area Type | Recommended Depth | Why This Depth? |
|---|---|---|
| Fire Pit Seating Area | 3–4 inches | Stable walking surface, conceals landscape fabric, comfortable underfoot |
| Decorative Border | 2–3 inches | Clean visual definition, easy to maintain, lower material cost |
| Base Layer (Sub-base) | 4–6 inches | Maximum drainage, prevents sinking, creates solid foundation |
| Safety Zone (near pit) | 3 inches | Non-flammable surface, keeps sparks from reaching combustible ground |
How much area will one ton of gravel cover at different depths? Use this reference to plan your fire pit area:
| Depth | Coverage per Ton (sq ft) | Equivalent Fire Pit Diameter |
|---|---|---|
| 2 inches | 100–120 sq ft | ~11-12 ft circle |
| 3 inches | 70–80 sq ft | ~10 ft circle |
| 4 inches | 50–60 sq ft | ~8 ft circle |
Each gravel type has distinct advantages for fire pit applications. Here's a detailed comparison to help you choose:
Click any material to select it in the calculator above and see instant results:
Understand what to budget for your fire pit gravel project. Here's a breakdown of material and installation costs:
| Material | Price per Ton | Typical Fire Pit Area (10 ft Ø, 3") |
|---|---|---|
| Pea Gravel | $30–$60 | $35–$70 (1.1 tons) |
| River Rock | $50–$100 | $55–$110 (1.1 tons) |
| Lava Rock | $80–$150 | $85–$160 (1.0 tons) |
| Crushed Stone (Base) | $20–$50 | $40–$100 (2.0 tons for 6" base) |
💰 Complete 10 ft Fire Pit Area — DIY vs Professional
See how the calculator works for common fire pit projects:
Follow these simple steps to calculate exactly how much gravel you need for your fire pit area:
For circular areas (most common): measure the diameter from edge to edge. Your gravel area should extend 3-4 feet beyond the fire pit itself. For a 3 ft fire pit, your total gravel area should be at least 9-11 ft in diameter.
For a two-layer system: install 4-6 inches of crushed stone as a base layer, then 2-3 inches of pea gravel or lava rock on top. For a single layer, use 3-4 inches total. Greater depth provides better drainage and stability.
Circle: π × radius² × depth (ft) ÷ 27. Example: a 10 ft diameter area at 3 inches deep = π × 5² × 0.25 ÷ 27 = 0.73 cubic yards. Rectangle: length × width × depth (ft) ÷ 27.
Multiply cubic yards by the material density. Pea gravel: ×1.3, lava rock: ×1.2, river rock: ×1.4, crushed stone: ×1.5. Example: 0.73 × 1.3 = 0.95 tons of pea gravel for a 10 ft fire pit area.
Multiply tons by price per ton for total cost. For bags: (tons × 2,000) ÷ bag weight, then round up. Always add 10-15% extra for compaction and settling. For larger fire pit areas, bulk delivery is much more cost-effective than bags.
A standard 10 ft diameter fire pit area at 3 inches deep requires approximately 1 ton of pea gravel (about 0.73 cubic yards). For a 12 ft area at 4 inches, expect about 2 tons. Use the formula: π × radius² × depth (ft) ÷ 27 × density. The calculator above will give you exact figures for your specific fire pit dimensions and gravel type.
Pea gravel is the #1 choice for fire pit seating areas — it's comfortable, affordable ($30-60/ton), and drains well. For the zone nearest the fire pit, lava rock is ideal because it's naturally heat-resistant and decorative. Use crushed stone for the base layer (4-6 inches) for maximum stability. Many homeowners use a combination: lava rock near the fire pit, pea gravel for the seating area, and river rock for decorative borders.
For a single layer: 3-4 inches total. For a two-layer system: 4-6 inches of crushed stone base + 2-3 inches of surface gravel (pea gravel or lava rock). The base layer provides drainage and prevents sinking, while the surface layer provides the finished look and comfortable walking surface. Deeper gravel also reduces the risk of weeds pushing through over time.
Yes, pea gravel is completely safe around a fire pit. It's non-flammable, provides excellent drainage (preventing water pooling around the fire), and creates a stable surface. Keep pea gravel 6-12 inches from the fire pit edge to prevent stones from being accidentally kicked into the fire. For the immediate zone around the fire pit, lava rock offers even better heat resistance and is a popular complementary material.
Calculate bags: (Tons × 2,000) ÷ Bag Weight, then round up. A 10 ft fire pit area at 3 inches deep with pea gravel needs about 38 bags at 50 lb each (0.95 tons). A 12 ft area needs about 60 bags. For projects over 1 ton, bulk delivery is significantly cheaper than buying bags. Use the calculator to compare bag vs bulk costs for your specific project.
A DIY gravel fire pit area costs $180-480 for a 10 ft diameter project including materials (pea gravel, base layer, landscape fabric, edging, and optional steel fire ring). Professional installation costs $1,000-3,500 including labor. The biggest cost variables are: gravel type (pea gravel $30-60/ton vs decorative rock $100+/ton), whether you install a base layer, and whether you add a fire ring or stone border. Bulk delivery is most cost-effective for projects over 1 ton.