{
  "slug": "pool-gallons-rectangular-calculator",
  "title": "Rectangular Pool Gallons Calculator",
  "heading": "Rectangular Pool Gallons Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/pool-gallons-rectangular-calculator",
  "summary": "Convert a rectangular pool's dimensions into total gallons for chemical dosing.",
  "description": "Every pool chemical — chlorine, algaecide, pH adjuster, shock — is dosed against total pool volume in gallons, so getting an accurate gallon count is the foundation of correct water balancing. A rectangular pool's volume is straightforward: length times width times average depth times a conversion constant of 7.5 gallons per cubic foot, since that's how many gallons fit in one cubic foot of water. Average depth matters because most residential pools slope from a shallow end to a deep end rather than holding one constant depth, so using the average of the two rather than either extreme gives a far more accurate total than assuming a flat depth throughout. This calculator takes length, width, shallow depth, and deep depth, averages the two depths, and multiplies out to total gallons. Under-dosing chemicals because your gallon estimate was too low leaves a pool vulnerable to algae and bacteria, while over-dosing wastes product and can irritate skin and eyes, so this conversion is worth getting right before every shock treatment or seasonal opening.",
  "formula": "Gallons = Length × Width × ((Shallow Depth + Deep Depth) ÷ 2) × 7.5",
  "dateModified": "2026-09-06",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=pool-gallons-rectangular-calculator",
  "inputs": [
    {
      "id": "length",
      "label": "Length",
      "kind": "number",
      "hint": null,
      "default": 32,
      "unit": "ft",
      "min": 5,
      "max": null
    },
    {
      "id": "width",
      "label": "Width",
      "kind": "number",
      "hint": null,
      "default": 16,
      "unit": "ft",
      "min": 5,
      "max": null
    },
    {
      "id": "shallowDepth",
      "label": "Shallow end depth",
      "kind": "number",
      "hint": null,
      "default": 3,
      "unit": "ft",
      "min": 1,
      "max": 12
    },
    {
      "id": "deepDepth",
      "label": "Deep end depth",
      "kind": "number",
      "hint": null,
      "default": 6,
      "unit": "ft",
      "min": 1,
      "max": 16
    }
  ],
  "outputs": [
    {
      "id": "gallons",
      "label": "Total pool gallons",
      "format": "number",
      "hint": null,
      "primary": true
    },
    {
      "id": "avgDepth",
      "label": "Average depth",
      "format": "decimal",
      "hint": "ft",
      "primary": false
    },
    {
      "id": "cubicFeet",
      "label": "Total cubic feet",
      "format": "number",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Length: 32 ft",
      "Width: 16 ft",
      "Shallow end depth: 3 ft",
      "Deep end depth: 6 ft"
    ],
    "outputs": [
      "Total pool gallons: 17,280",
      "Average depth: 4.5",
      "Total cubic feet: 2,304"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter length (ft).",
      "Enter width (ft).",
      "Enter shallow end depth (ft).",
      "Enter deep end depth (ft).",
      "Read your total pool gallons 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": {
        "length": 19,
        "width": 10,
        "shallowDepth": 1.7999999999999998,
        "deepDepth": 3.5999999999999996
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "length": 32,
        "width": 16,
        "shallowDepth": 3,
        "deepDepth": 6
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "length": 51,
        "width": 26,
        "shallowDepth": 4.800000000000001,
        "deepDepth": 9.600000000000001
      }
    }
  ],
  "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": "Why multiply by 7.5?",
      "a": "One cubic foot of water holds 7.48 gallons, rounded to 7.5 for practical pool math, so multiplying a pool's cubic footage by 7.5 converts volume directly into gallons."
    },
    {
      "q": "Why use average depth instead of deep end depth?",
      "a": "Using only the deep end depth overstates volume since most of the pool's shallow-to-deep slope holds less water than the deepest point, so averaging the two gives a far more accurate total."
    },
    {
      "q": "How accurate does my gallon count need to be for chemicals?",
      "a": "Within 5-10% is fine for most chlorine and shock dosing since product labels already build in some tolerance, but very inaccurate estimates can lead to real under- or over-dosing."
    },
    {
      "q": "Does a rectangular pool with a shallow shelf change this math?",
      "a": "A tanning shelf or bench reduces total volume slightly; for most residential pools this is a small enough fraction that it can be ignored, but for precise dosing on pools with large shelves, subtract the shelf's estimated volume separately."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/pool-gallons-round-calculator",
    "https://www.revenuelab.fyi/toolbox/pool-gallons-oval-calculator",
    "https://www.revenuelab.fyi/toolbox/pool-shock-calculator"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Rectangular Pool Gallons Calculator (https://www.revenuelab.fyi/toolbox/pool-gallons-rectangular-calculator)"
}