{
  "id": "gravel",
  "version": "de8d22270bb4",
  "status": "published",
  "name": "Gravel Calculator",
  "question": "How much gravel do I need?",
  "summary": "Computes the volume of gravel for a rectangular or round area at a depth, in cubic yards and cubic metres, its weight in tons at a bulk density, and the cost.",
  "category": "construction",
  "url": "https://www.acalculator.org/construction/gravel-calculator",
  "markdown": "https://www.acalculator.org/construction/gravel-calculator.md",
  "kind": "function",
  "method": "volume = area × depth; weight = volume × density; cubic yards = cubic feet ÷ 27; tons = pounds ÷ 2,000",
  "assumptions": [
    "Rectangle: length × width. Circle: π × diameter² ÷ 4.",
    "The default density is dry gravel, 105 lb/ft³ (1,680 kg/m³), from the Engineering ToolBox. Wet gravel is about 125 lb/ft³. Ask your supplier for the density of their stone.",
    "The volume is the loose volume of the layer. It adds nothing for compaction or waste."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "shape": {
        "title": "Area shape",
        "description": "A rectangle, or a circle.",
        "type": "string",
        "enum": [
          "rectangle",
          "circle"
        ]
      },
      "len": {
        "title": "Length",
        "description": "The length of the area.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "length",
        "exclusiveMinimum": 0,
        "maximum": 100000
      },
      "wid": {
        "title": "Width",
        "description": "The width of the area.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "length",
        "exclusiveMinimum": 0,
        "maximum": 100000
      },
      "dia": {
        "title": "Diameter",
        "description": "The diameter of the round area.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "length",
        "exclusiveMinimum": 0,
        "maximum": 100000
      },
      "dep": {
        "title": "Depth",
        "description": "How thick the layer of gravel is.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "length",
        "exclusiveMinimum": 0,
        "maximum": 1000
      },
      "density": {
        "title": "Density",
        "description": "The bulk density of the gravel. Dry gravel is about 105 lb/ft³; wet gravel about 125 lb/ft³.",
        "type": [
          "number",
          "string"
        ],
        "x-quantity": "density",
        "exclusiveMinimum": 0,
        "maximum": 20000
      },
      "price": {
        "title": "Price",
        "description": "The price per ton, tonne or cubic yard. Leave empty to skip the cost.",
        "type": "number",
        "x-unit": "USD",
        "minimum": 0,
        "maximum": 1000000
      },
      "per": {
        "title": "Price per",
        "description": "The unit the price is for.",
        "type": "string",
        "enum": [
          "ton",
          "t",
          "yd3"
        ]
      }
    }
  },
  "outputs": {
    "cubicYards": {
      "label": "Gravel",
      "description": "The volume of gravel in cubic yards.",
      "format": "quantity",
      "unit": "yd3"
    },
    "cubicFeet": {
      "label": "Cubic feet",
      "description": "The volume of gravel in cubic feet.",
      "format": "quantity",
      "unit": "ft3"
    },
    "cubicMeters": {
      "label": "Cubic metres",
      "description": "The volume of gravel in cubic metres.",
      "format": "quantity",
      "unit": "m3"
    },
    "tons": {
      "label": "Weight in tons",
      "description": "The volume × the density, in US short tons of 2,000 lb.",
      "format": "quantity",
      "unit": "ton"
    },
    "tonnes": {
      "label": "Weight in tonnes",
      "description": "The volume × the density, in metric tonnes of 1,000 kg.",
      "format": "quantity",
      "unit": "t"
    },
    "cost": {
      "label": "Cost",
      "description": "The weight or volume in the price unit × the price.",
      "format": "money"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "shape": "rectangle",
      "len": 6.096,
      "wid": 3.048,
      "dia": 3.048,
      "dep": 0.1016,
      "density": 1681.9386542658149,
      "per": "ton"
    },
    "outputs": {
      "cubicYards": 1.8877897728000002,
      "cubicFeet": 1.8877897728000002,
      "cubicMeters": 1.8877897728000002,
      "tons": 3175.1465900000007,
      "tonnes": 3175.1465900000007
    },
    "text": "Covering the area 4 in deep takes 2.47 yd³ of gravel, about 3.5 ton."
  },
  "examples": [
    {
      "given": {
        "shape": "rectangle",
        "len": 6.096,
        "wid": 3.048,
        "dep": 0.1016,
        "density": 1681.9386542658149,
        "per": "ton",
        "price": 40
      },
      "expect": {
        "cubicFeet": 1.8877897728000002,
        "tons": 3175.1465900000007,
        "cost": 140.00000000000003
      },
      "source": "hand calculation in content.mdx: 20 × 10 × 4/12 = 66.67 ft³ = 2.47 yd³; × 105 lb/ft³ = 7,000 lb = 3.5 tons; × $40 = $140"
    },
    {
      "given": {
        "shape": "circle",
        "dia": 3.6576000000000004,
        "dep": 0.07619999999999999,
        "density": 1681.9386542658149,
        "per": "yd3",
        "price": 55
      },
      "expect": {
        "cubicFeet": 0.8006399750363073,
        "cost": 57.59586531581287
      },
      "source": "hand calculation in content.mdx: π × 12² ÷ 4 × 0.25 = 9π = 28.27 ft³ = 1.047 yd³; × $55 = $57.60"
    },
    {
      "given": {
        "shape": "rectangle",
        "len": 10,
        "wid": 3,
        "dep": 0.1,
        "density": 1680,
        "per": "t",
        "price": 50
      },
      "expect": {
        "cubicMeters": 3,
        "tonnes": 5040,
        "cost": 252
      },
      "source": "hand calculation in content.mdx: 10 × 3 × 0.1 = 3 m³; × 1,680 kg/m³ = 5,040 kg = 5.04 t; × $50 = $252",
      "tolerance": 1e-12
    }
  ],
  "sources": [
    "Engineering ToolBox, Dirt and Mud - Densities: gravel, dry 105 lb/ft³ (1,680 kg/m³); gravel, wet 125 lb/ft³ (2,000 kg/m³). https://www.engineeringtoolbox.com/dirt-mud-densities-d_1727.html",
    "NIST SP 811 (2008), Appendix B: 1 ft = 0.3048 m and 1 lb = 0.45359237 kg exactly; 1 short ton = 2,000 lb."
  ],
  "related": [
    "stone",
    "cubic-yards",
    "concrete",
    "mulch"
  ],
  "changelog": []
}