{
  "slug": "paint",
  "title": "Paint Calculator",
  "heading": "Paint Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/paint",
  "summary": "Gallons of paint for walls, ceilings, and trim.",
  "description": "A gallon covers roughly 350 square feet per coat on primed drywall. Dark colours over light walls almost always need two coats, and fresh drywall needs primer on top of that.",
  "formula": "Gallons = (Wall area − openings) × Coats ÷ Coverage per gallon.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=paint",
  "inputs": [
    {
      "id": "perimeter",
      "label": "Room perimeter",
      "kind": "number",
      "hint": null,
      "default": 48,
      "unit": "ft",
      "min": 0,
      "max": null
    },
    {
      "id": "height",
      "label": "Ceiling height",
      "kind": "number",
      "hint": null,
      "default": 9,
      "unit": "ft",
      "min": 1,
      "max": null
    },
    {
      "id": "doors",
      "label": "Doors",
      "kind": "number",
      "hint": null,
      "default": 2,
      "unit": null,
      "min": 0,
      "max": null
    },
    {
      "id": "windows",
      "label": "Windows",
      "kind": "number",
      "hint": null,
      "default": 3,
      "unit": null,
      "min": 0,
      "max": null
    },
    {
      "id": "coats",
      "label": "Coats",
      "kind": "number",
      "hint": null,
      "default": 2,
      "unit": null,
      "min": 1,
      "max": 4
    },
    {
      "id": "coverage",
      "label": "Coverage per gallon",
      "kind": "number",
      "hint": null,
      "default": 350,
      "unit": "sq ft",
      "min": 100,
      "max": null
    },
    {
      "id": "price",
      "label": "Price per gallon",
      "kind": "number",
      "hint": null,
      "default": 48,
      "unit": "$",
      "min": 0,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "gallons",
      "label": "Paint needed (gallons)",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "cans",
      "label": "Gallon cans to buy",
      "format": "number",
      "hint": null,
      "primary": false
    },
    {
      "id": "cost",
      "label": "Estimated paint cost",
      "format": "currency",
      "hint": null,
      "primary": false
    },
    {
      "id": "paintable",
      "label": "Paintable wall area (sq ft)",
      "format": "number",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Room perimeter: 48 ft",
      "Ceiling height: 9 ft",
      "Doors: 2",
      "Windows: 3",
      "Coats: 2",
      "Coverage per gallon: 350 sq ft",
      "Price per gallon: 48 $"
    ],
    "outputs": [
      "Paint needed (gallons): 2",
      "Gallon cans to buy: 2",
      "Estimated paint cost: $96.00",
      "Paintable wall area (sq ft): 345"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter room perimeter (ft).",
      "Enter ceiling height (ft).",
      "Enter doors.",
      "Enter windows.",
      "Enter coats.",
      "Enter coverage per gallon (sq ft).",
      "Enter price per gallon ($).",
      "Read your paint needed (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": {
        "perimeter": 29,
        "height": 9,
        "doors": 1,
        "windows": 2,
        "coats": 1,
        "coverage": 200,
        "price": 29
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "perimeter": 48,
        "height": 9,
        "doors": 2,
        "windows": 3,
        "coats": 2,
        "coverage": 350,
        "price": 48
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "perimeter": 77,
        "height": 9,
        "doors": 3,
        "windows": 5,
        "coats": 3,
        "coverage": 550,
        "price": 77
      }
    }
  ],
  "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 does the paint calculator work?",
      "a": "A gallon covers roughly 350 square feet per coat on primed drywall. Dark colours over light walls almost always need two coats, and fresh drywall needs primer on top of that. The underlying maths is: Gallons = (Wall area − openings) × Coats ÷ Coverage per gallon."
    },
    {
      "q": "What do I need to enter?",
      "a": "7 values: room perimeter, ceiling height, doors, windows, coats, coverage per gallon, and price per gallon. Each field starts with a sensible default, so you can change one number at a time and watch the result move."
    },
    {
      "q": "What does the paint needed (gallons) result mean?",
      "a": "It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds."
    },
    {
      "q": "Is this calculator free, and do I need an account?",
      "a": "Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser."
    },
    {
      "q": "How accurate is the result?",
      "a": "It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/drywall",
    "https://www.revenuelab.fyi/toolbox/wallpaper",
    "https://www.revenuelab.fyi/toolbox/square-footage"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Paint Calculator (https://www.revenuelab.fyi/toolbox/paint)"
}