Gravel Calculator

How to Calculate Gravel for Your Project

Three measurements drive the calculation: length, width, and depth. Multiply them together to get a volume in cubic feet, then divide by 27 to convert to cubic yards — the standard unit for bulk material orders in the US. The formula for a rectangular area is:

Cubic yards = (Length ft × Width ft × Depth ft) ÷ 27

If your depth is in inches, divide by 12 first to get feet. For circular areas (tree rings, round patios), use π × radius² × depth in feet, then divide by 27. Triangular sections use half the base times the height times depth, divided by 27.

Once you have cubic yards, multiply by the material density (in tons per cubic yard) to get the tonnage your supplier will quote. Density varies by material type — see the table below. If you need to move material around the site, see the Cubic Yard Calculator for volume-only estimates, or consult the Excavator Rental Guide to size the right equipment for excavation and grading work.

Worked Example: Gravel for a 2-Car Driveway

A standard 2-car driveway measures approximately 20 feet wide by 24 feet long (480 sq ft). Most contractors use a two-layer system: a 4-inch compacted base of #57 crushed stone, topped with a 2-inch surface layer of 3/4-inch crushed limestone or gravel.

• Base layer: 480 sq ft × (4 in ÷ 12) = 160 cubic feet ÷ 27 = 5.93 cubic yards × 1.5 t/CY = 8.9 tons
• Top layer: 480 sq ft × (2 in ÷ 12) = 80 cubic feet ÷ 27 = 2.96 cubic yards × 1.5 t/CY = 4.4 tons
• Combined total: ~8.9 cubic yards, ~13.3 tons of crushed stone
• With 15% compaction overage: ~10.2 cubic yards, ~15.3 tons to order

Angular crushed stone compacts by 15–25%, so ordering 15% extra is the industry standard for driveway projects. A second delivery for a small shortfall typically costs more than the overage material itself.

Gravel Types and Densities

Gravel density determines how many tons you need for a given volume. All values are in tons per cubic yard. Actual density varies with moisture content and compaction — these are representative industry averages.

Gravel Type	Density (tons/CY)	Common Use
Pea Gravel	1.4–1.6	Pathways, landscaping, playgrounds
#57 Crushed Stone	1.4–1.6	Driveway base, drainage, concrete aggregate
#411 / Crusher Run	1.50	Driveway base, compacted sub-base
3/4" Crushed Stone	1.4–1.5	Driveway surface, drainage
Crushed Limestone	1.4–1.6	Driveways, road base, fill
River Rock	1.3–1.75	Decorative, erosion control, dry creek beds
Decomposed Granite	1.5–1.7	Pathways, patios, desert landscaping
Recycled Concrete	1.4–1.6	Sub-base, fill, low-traffic driveways
Base Gravel / Road Base	1.35	Sub-base for driveways, foundations
Marble Chips	1.3–1.6	Decorative landscaping
Lava Rock	0.8–1.4	Decorative, fire pit surrounds

Recommended Gravel Depth by Application

Depth requirements vary by load, drainage needs, and freeze-thaw cycles. These are industry-standard minimums — colder climates and heavy vehicle traffic generally warrant going to the upper end of each range.

Application	Recommended Depth	Notes
Driveway base layer	4–6 inches	#57 or road base; compact in 2” lifts
Driveway top layer	2–3 inches	3/4” crushed stone or limestone
Walkway / path	2–3 inches	Pea gravel or decomposed granite
Patio base	4–6 inches	Compacted gravel under pavers or flagstone
French drain	8–12 inches	#57 stone around perforated pipe
Foundation drainage	6–12 inches	Washed stone around footings
Retaining wall backfill	12+ inches	Drainage layer behind wall
Under concrete slab	4–6 inches	Compacted base gravel
Playground surface	6–8 inches minimum	ASTM F1292 fall height requirements apply
Garden / decorative	2–3 inches	Sufficient for weed suppression

For projects that need excavation before laying gravel — driveways, French drains, patio bases — the Loader and Dozer Rental Guide covers how to choose the right machine for moving material on-site.

Coverage Rates: How Far Does a Ton Go?

Coverage depends on gravel density and the depth you’re applying. Lighter materials like pea gravel spread further per ton than denser crushed stone. The table below uses representative values for standard crushed stone (1.5 t/CY) and pea gravel (1.5 t/CY at the lighter end of its range).

Depth	Standard Crushed Stone (sq ft/ton)	Pea Gravel (sq ft/ton)
2 inches	100–120	120–133
3 inches	70–80	80–100
4 inches	50–60	60–80

As a quick rule of thumb: at 2 inches deep, one ton of standard gravel covers roughly 100 square feet — about the size of a 10×10-foot patio. Double the depth and you roughly halve the coverage.

Gravel Costs and Delivery

Prices shift by material type, region, and order volume. The ranges below are 2025 market prices per HomeGuide — expect your local quarry to differ, sometimes by a wide margin.

Gravel Type	Per Ton	Per Cubic Yard
Pea Gravel	$30–$55	$40–$75
Crushed Stone	$15–$50	$20–$70
Crushed Limestone	$30–$38	$35–$54
River Rock	$40–$120	$55–$100
Decomposed Granite	$35–$65	$40–$80
Base Gravel / Road Base	$18–$31	$25–$62

Delivery fees are typically separate from material cost. Typical ranges for 2025:

• Local delivery (0–10 miles): $50–$75
• Standard delivery (10–25 miles): $75–$150
• Long-distance delivery (25+ miles): $150–$300+
• Per-mile fee beyond the free zone: $2–$15 per mile (varies by supplier)
• Short-load fee for orders below the minimum: typically around $20

Most suppliers require a minimum order. Three tons is the common residential floor, though some will go as low as one ton and others require five. If your project is smaller than that, a local landscape supplier may sell by the bag or half-yard. On the other end, many suppliers waive delivery fees above a certain tonnage threshold — rounding up your order can occasionally cost less than paying the short-load fee.