River Rock Coverage Calculator (1–3" & 3–5" Sizes)
Estimate exact cubic yards and tonnage for smooth landscape river stones in 1–3 inch and 3–5 inch sizing.
Interactive Material & Cost Estimator
HomeYardMath.com — Hardware Store Shopping List
Estimated Material Needed 120 sq ft @ 3.5" depth (+10% buffer)
Bulk Volume (Cubic Yards) 1.43 38.5 cubic feet
Estimated Total Weight 1.89 US Tons (3,779 lbs)
Store Bag Count 77 bags
Pallet Estimate (56 bags) ~1.38 pallets
Estimated Project Material Cost Bulk Saves $266
Retail Package Total $460.46 Before local sales tax
Bulk + Truck Delivery $194.81 Includes $95 delivery
Quick Reference Coverage Chart (Gravel & Stone)
Instant pre-calculated material estimates for common US residential project sizes before compaction buffer:
| Typical US Project | Area | Depth | Volume | Weight | Store Bags |
|---|---|---|---|---|---|
| Flower Bed Accent Border (3 ft × 20 ft) | 60 sq ft | 3 inches | 0.68 cu yd | 0.90 tons (1,800 lbs) | 37 bags |
| Dry Creek Bed Drainage (4 ft × 30 ft) | 120 sq ft | 4 inches | 1.63 cu yd | 2.16 tons (4,320 lbs) | 88 bags |
Engineering Formula & Material Density Constant
Cubic Yards = (Length × Width × (Depth ÷ 12)) ÷ 27
Smooth rounded river rock weighs roughly 2,650 lbs per cubic yard. Larger 3–5 inch stones require a slightly deeper bed to prevent soil peek-through.
Choosing the Right River Rock Size
Use 1 to 2-inch river rock for standard garden beds and walkable paths. Use 3 to 5-inch boulders for dry creek beds, erosion control on slopes, and water runoff channels.
Frequently Asked Questions
How many bags of river rock make a cubic yard?
54 standard 0.5 cu ft bags equal 1 cubic yard.
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