{
  "slug": "river-rock-tons-calculator",
  "title": "River Rock Tons Calculator",
  "heading": "River Rock Tons Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/river-rock-tons-calculator",
  "summary": "Tonnage needed for a decorative river rock bed or drainage area.",
  "description": "River rock is a popular decorative and drainage ground cover sold by the ton, and because it's typically spread deeper than mulch (often 2-4 inches to fully hide the landscape fabric or soil beneath) getting an accurate tonnage estimate avoids a mid-project run back to the stone yard. This calculator takes your area and depth, computes cubic yards, and multiplies by river rock's density, which runs lighter than crushed angular gravel at around 1.3 tons per cubic yard because rounded river stone packs less tightly than crushed stone with sharp interlocking edges. It applies a waste factor to cover the reality that rock spreads unevenly around plants, borders, and drainage features, and larger decorative rock (2-4 inch or bigger) in particular tends to leave more voids and require a bit more volume than fine gravel to achieve full visual coverage. Use this for dry creek beds, foundation drainage borders, and decorative accent areas around a home's perimeter.",
  "formula": "Cubic Yards = (Area × Depth ft) ÷ 27. Tons = Cubic Yards × Density (tons/cu yd) × (1 + Waste%).",
  "dateModified": "2026-09-06",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=river-rock-tons-calculator",
  "inputs": [
    {
      "id": "area",
      "label": "Area",
      "kind": "number",
      "hint": null,
      "default": 150,
      "unit": "sq ft",
      "min": 5,
      "max": null
    },
    {
      "id": "depthIn",
      "label": "Depth",
      "kind": "number",
      "hint": null,
      "default": 3,
      "unit": "in",
      "min": 1,
      "max": 12
    },
    {
      "id": "density",
      "label": "River rock density",
      "kind": "number",
      "hint": null,
      "default": 1.3,
      "unit": "tons/cu yd",
      "min": 1,
      "max": 1.8
    },
    {
      "id": "wastePct",
      "label": "Waste factor",
      "kind": "number",
      "hint": null,
      "default": 10,
      "unit": "%",
      "min": 0,
      "max": 25
    }
  ],
  "outputs": [
    {
      "id": "tons",
      "label": "River rock needed",
      "format": "decimal",
      "hint": "tons",
      "primary": true
    },
    {
      "id": "cubicYards",
      "label": "Raw cubic yards",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "area",
      "label": "Area covered",
      "format": "number",
      "hint": "sq ft",
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Area: 150 sq ft",
      "Depth: 3 in",
      "River rock density: 1.3 tons/cu yd",
      "Waste factor: 10 %"
    ],
    "outputs": [
      "River rock needed: 1.99",
      "Raw cubic yards: 1.39",
      "Area covered: 150"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter area (sq ft).",
      "Enter depth (in).",
      "Enter river rock density (tons/cu yd).",
      "Enter waste factor (%).",
      "Read your river rock needed on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "area": 90,
        "depthIn": 1.7999999999999998,
        "density": 1,
        "wastePct": 6
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "area": 150,
        "depthIn": 3,
        "density": 1.3,
        "wastePct": 10
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "area": 240,
        "depthIn": 4.800000000000001,
        "density": 1.8,
        "wastePct": 16
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "How deep should river rock be spread?",
      "a": "2-3 inches is standard for decorative beds over landscape fabric; drainage-focused areas like dry creek beds often go 3-4 inches to fully conceal the fabric and handle water flow."
    },
    {
      "q": "Why is river rock's density lower than crushed gravel?",
      "a": "Rounded river stones don't interlock as tightly as angular crushed stone, leaving more air gaps between pieces, which lowers the overall weight per cubic yard even though individual stones are just as dense."
    },
    {
      "q": "Does larger rock size need more material for the same coverage?",
      "a": "Yes, larger decorative rock (2-4 inch) has bigger voids between pieces and can require modestly more volume than pea gravel to achieve the same visually solid coverage at the same depth."
    },
    {
      "q": "Should I put landscape fabric under river rock?",
      "a": "Yes, in almost all cases — fabric prevents rock from sinking into soil and dramatically reduces weed growth, which keeps the bed from needing to be re-topped with more rock as often."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/gravel-tons-calculator",
    "https://www.revenuelab.fyi/toolbox/sand-tons-calculator",
    "https://www.revenuelab.fyi/toolbox/decomposed-granite-calculator"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — River Rock Tons Calculator (https://www.revenuelab.fyi/toolbox/river-rock-tons-calculator)"
}