Rock Volume & Materials Estimator

Rock Calculator

Calculate rock volume, weight, and optional cost using multiple shapes and material density inputs.

Material Bulk density (kg/m³) Cost estimator

Landscaping rock typically costs $35 to $120 per ton for material, or $50 to $200 per cubic yard delivered, depending on rock type, size, and your location. A standard 2-inch deep coverage layer for a 200 square foot garden bed requires approximately 1.2 to 1.5 tons of rock.

Enter your project dimensions, desired depth, and rock type in the calculator above to instantly get your volume in cubic yards, weight in tons, and a full cost estimate — including material, delivery, and optional installation labor.

Delivery costs vary by $200 to $800 for the same project between suppliers. Weight (tons) and volume (cubic yards) are the two figures that matter when comparing quotes — don’t buy by the bag when bulk pricing is available. Use this calculator before calling suppliers to prevent over-ordering or running short mid-project.

How to Use the Rock Calculator

Enter 4 values to calculate your rock order: the length and width of the coverage area in feet, the desired depth in inches, and the type of rock. The calculator returns cubic yards, tons, and an estimated cost range for your area.

Enter area dimensions — length and width in feet; for irregular shapes, break the area into rectangles and add totals
Select rock depth — 2 to 3 inches for decorative coverage, 4 to 6 inches for weed suppression, 6 to 12 inches for drainage or base layers
Choose rock type — each rock type has a different weight per cubic yard (lava rock is lighter; river rock and crushed granite are heavier)
Review tons and cubic yards — use tons when buying from bulk suppliers; use cubic yards for delivery truck estimates
Add delivery and labor — most bulk rock suppliers charge by the ton delivered; installation adds $50 to $100 per ton for spreading

Rock Types, Weight, and Coverage — 2026 US Averages

Different rock types have significantly different densities. Choosing the wrong type when estimating results in under-ordering (project delays) or over-ordering (wasted cost). Use the table below to select the correct density for your material.

Rock Type	Lbs per Cu Yd	Tons per Cu Yd	Cu Yds per Ton	Best Use
Decomposed Granite	2,700 lbs	1.35 tons	0.74 cu yd	Pathways, driveways
Crushed Limestone	2,565 lbs	1.28 tons	0.78 cu yd	Base layers, drainage
River Rock (pea gravel)	2,800 lbs	1.40 tons	0.71 cu yd	Garden beds, borders
Crushed Granite	2,700 lbs	1.35 tons	0.74 cu yd	Pathways, compactable base
Lava Rock	1,500 lbs	0.75 tons	1.33 cu yd	Decorative, mulch replacement
Marble Chips	2,565 lbs	1.28 tons	0.78 cu yd	Decorative garden beds
Crushed Concrete	2,025 lbs	1.01 tons	0.99 cu yd	Base fill, driveway sub-base
White Marble Gravel	2,430 lbs	1.22 tons	0.82 cu yd	Decorative, high-contrast beds

Rock Coverage by Depth — Square Feet per Ton

Coverage varies significantly by depth. A 2-inch depth is adequate for decorative groundcover and weed suppression in established beds. Drainage applications and high-traffic paths typically require 4 to 6 inches of compacted rock.

Rock Type	1 Inch Deep	2 Inches Deep	3 Inches Deep	4 Inches Deep
Pea Gravel / River Rock	240 sq ft/ton	120 sq ft/ton	80 sq ft/ton	60 sq ft/ton
Decomposed Granite	240 sq ft/ton	120 sq ft/ton	80 sq ft/ton	60 sq ft/ton
Crushed Limestone	250 sq ft/ton	125 sq ft/ton	83 sq ft/ton	62 sq ft/ton
Lava Rock	430 sq ft/ton	215 sq ft/ton	143 sq ft/ton	107 sq ft/ton
Marble Chips	250 sq ft/ton	125 sq ft/ton	83 sq ft/ton	62 sq ft/ton

Rock Landscaping Cost by Project Type — 2026

Costs below include material and standard delivery within 20 miles. Installation (spreading, grading, and edging) adds $50 to $100 per ton or $2 to $4 per square foot, depending on site access and slope.

Project Type	Typical Area	Depth	Tons Needed	Estimated Cost (Material)
Small garden bed	100 sq ft	2 inches	0.6 – 0.8 tons	$50 – $120
Medium garden beds	300 sq ft	2 inches	1.8 – 2.2 tons	$150 – $280
Full front yard	1,000 sq ft	3 inches	6.5 – 8.0 tons	$400 – $900
Gravel driveway (base)	1,800 sq ft	6 inches	20 – 26 tons	$800 – $2,200
Backyard drainage trench	150 linear ft	12 inches wide/deep	8 – 12 tons	$350 – $900
Playground border	500 sq ft	6 inches	9 – 12 tons	$500 – $1,100
Commercial parking lot base	5,000 sq ft	6 inches	55 – 70 tons	$2,200 – $6,000

Full Rock Project Cost Breakdown

Material cost is only one part of a rock landscaping project. Delivery, fabric underlayment, edging, and labor all add to the total. Every component below should appear on a legitimate landscaping contractor quote.

Cost Component	Cost Range	% of Total	Notes
Rock material (per ton)	$35 – $120/ton	35 – 55%	Varies by rock type and local availability
Delivery	$50 – $200 flat fee	10 – 20%	Most suppliers have minimum delivery tonnage
Landscape fabric	$0.05 – $0.30/sq ft	3 – 8%	Required for weed suppression under decorative rock
Edging / borders	$1.50 – $5/linear ft	5 – 12%	Steel, aluminum, or plastic; prevents rock spread
Site prep / grading	$0.50 – $2/sq ft	5 – 10%	Leveling and slope correction before rock placement
Labor (spreading)	$50 – $100/ton	20 – 35%	Manual spreading and grading; varies by site access
Weed treatment	$0.10 – $0.30/sq ft	2 – 5%	Pre-emergent herbicide before fabric and rock installation

Rock Calculator Formulas — Manual Calculation

Use these formulas if you prefer to calculate without a calculator tool. All measurements should be converted to feet before calculating.

Step 1 — Calculate Volume in Cubic Feet

Volume (cubic feet) = Length (ft) × Width (ft) × Depth (ft)

Note: Convert depth from inches to feet by dividing by 12. Example: 3 inches = 3 ÷ 12 = 0.25 feet

Step 2 — Convert to Cubic Yards

Cubic yards = Cubic feet ÷ 27

Example: A 20 × 15 ft bed at 3 inches deep = 20 × 15 × 0.25 = 75 cubic feet ÷ 27 = 2.78 cubic yards

Step 3 — Convert to Tons

Tons = Cubic yards × (lbs per cubic yard ÷ 2,000)

Example using river rock (2,800 lbs/cu yd): 2.78 cu yd × (2,800 ÷ 2,000) = 2.78 × 1.40 = 3.89 tons

Step 4 — Add 10% Waste Factor

Order Quantity = Calculated tons × 1.10

A 10% overage prevents running short due to uneven depth, spillage, or irregular area shapes. Excess rock is easy to store or use elsewhere; running short mid-installation causes delays and delivery surcharges.

Bulk Rock vs. Bagged Rock — Cost Comparison

Bagged rock from home improvement stores appears convenient but costs 3 to 6 times more per ton than bulk delivery for any project over 2 tons. For most residential landscaping projects, bulk delivery is the correct choice.

	Bagged (50 lb bag)	Bulk Ton Bag (1 ton)	Bulk Delivery (5+ tons)	Best For
Pea gravel — cost per ton	$300 – $500	$120 – $200	$35 – $80	Over 2 tons → bulk
Crushed granite — cost per ton	$350 – $600	$140 – $220	$40 – $90	Over 2 tons → bulk
River rock — cost per ton	$400 – $700	$150 – $250	$50 – $120	Over 1.5 tons → bulk
Lava rock — cost per ton	$500 – $900	$200 – $350	$80 – $160	Over 1 ton → bulk

How to Hire a Rock Landscaping Contractor

Verify contractor license — landscaping contractors require a separate license from general contractors in most states
Ask for weight tickets — all bulk rock deliveries should include a certified scale ticket showing actual weight delivered
Confirm fabric and edging is included — many low quotes exclude these and add them as change orders after site prep
Review the drainage plan — for drainage rock installations, verify slope direction and outlet point before work begins
Get at least 3 quotes — rock landscaping prices vary widely between contractors; the middle quote is usually the most reliable
Ask about waste disposal — if existing mulch, grass, or old rock is being removed, confirm whether removal and hauling is included
Check delivery windows — bulk rock often requires a dump truck; confirm your driveway or gate can accommodate the vehicle size

Frequently Asked Questions

How many tons of rock do I need for 1,000 square feet?

At 2 inches deep, 1,000 square feet requires approximately 6 to 7 tons of standard gravel (pea gravel, river rock, or crushed granite). At 3 inches deep, the same area needs 9 to 10 tons. Lava rock covers more area per ton due to its lower density — the same 1,000 square feet at 2 inches requires only 4 to 5 tons of lava rock.

What is the difference between cubic yards and tons for rock?

Cubic yards measure volume; tons measure weight. Suppliers can sell by either unit. To convert, you need the density of the specific rock type. River rock and crushed granite weigh approximately 1.35 to 1.40 tons per cubic yard. Lava rock weighs only 0.75 tons per cubic yard. Always confirm with your supplier which unit they use for pricing to avoid calculation errors.

How deep should landscaping rock be?

Two to three inches is the standard depth for decorative rock in garden beds, providing adequate weed suppression when installed over landscape fabric. For high-traffic pathways, 3 to 4 inches allows for compaction. Drainage trenches and French drains typically require 6 to 12 inches of washed stone. Driveway sub-base applications generally require 4 to 6 inches of compacted crushed stone.

Can I calculate rock for an irregular-shaped area?

Yes. Break the irregular area into manageable rectangles or triangles. Calculate the area of each section separately using the appropriate formula (length × width for rectangles; base × height ÷ 2 for triangles), then add the totals. For circular areas, use the formula: Area = 3.14 × radius × radius. Add a 10 to 15% overage to account for irregular edges and depth variation.

How much does rock delivery cost?

Rock delivery typically costs $50 to $200 per delivery for standard residential drops within 20 miles of the supplier. Most suppliers have a minimum order of 1 to 3 tons for delivery. Long-distance deliveries and difficult access sites (narrow gates, steep slopes) add $50 to $150 per trip. Crane or conveyor delivery for tight access areas costs $200 to $500 extra.