{
    "name": "Land Plot Area Calculator",
    "url": "https://calculators.geekmidst.com/calculators/land-plot-area-calculator",
    "markdown": "https://calculators.geekmidst.com/calculators/land-plot-area-calculator.md",
    "category": "Real estate",
    "description": "Find the area of a rectangular, triangular or irregular four-sided plot, or any shape from corner coordinates, in m², sq ft, acres and hectares.",
    "summary": "Measure the boundary of your plot and get its area in every common unit. Irregular four-sided plots are split along a diagonal into two triangles; any shape can be measured from corner coordinates.",
    "also_called": [
        "Acreage calculator",
        "Plot size calculator"
    ],
    "applies_to": "Worldwide",
    "last_updated": "2026-10-29",
    "computation": "Results are computed in the visitor’s browser on the HTML page. This API describes the calculator; it does not compute results.",
    "inputs": [
        {
            "name": "shape",
            "label": "Plot shape",
            "type": "select",
            "default": "rectangle",
            "options": {
                "rectangle": "Rectangle",
                "triangle": "Triangle (three sides)",
                "quad": "Irregular four sides + diagonal",
                "coords": "Any shape from corner coordinates"
            }
        },
        {
            "name": "unit",
            "label": "Lengths in",
            "type": "segmented",
            "default": "m",
            "options": {
                "m": "Metres",
                "ft": "Feet",
                "yd": "Yards"
            }
        },
        {
            "name": "length",
            "label": "Length",
            "type": "number",
            "default": "30",
            "shown_when": {
                "shape": "rectangle"
            }
        },
        {
            "name": "width",
            "label": "Width",
            "type": "number",
            "default": "20",
            "shown_when": {
                "shape": "rectangle"
            }
        },
        {
            "name": "side_a",
            "label": "Side A",
            "type": "number",
            "default": "30",
            "shown_when": {
                "shape": "triangle"
            }
        },
        {
            "name": "side_b",
            "label": "Side B",
            "type": "number",
            "default": "40",
            "shown_when": {
                "shape": "triangle"
            }
        },
        {
            "name": "side_c",
            "label": "Side C",
            "type": "number",
            "default": "50",
            "shown_when": {
                "shape": "triangle"
            }
        },
        {
            "name": "q_a",
            "label": "Side A",
            "type": "number",
            "default": "30",
            "shown_when": {
                "shape": "quad"
            }
        },
        {
            "name": "q_b",
            "label": "Side B",
            "type": "number",
            "default": "40",
            "shown_when": {
                "shape": "quad"
            }
        },
        {
            "name": "q_c",
            "label": "Side C",
            "type": "number",
            "default": "32",
            "shown_when": {
                "shape": "quad"
            }
        },
        {
            "name": "q_d",
            "label": "Side D",
            "type": "number",
            "default": "38",
            "shown_when": {
                "shape": "quad"
            }
        },
        {
            "name": "q_diag",
            "label": "Diagonal",
            "type": "number",
            "default": "50",
            "shown_when": {
                "shape": "quad"
            }
        },
        {
            "name": "coords",
            "label": "Corner points in order around the boundary (one “x, y” per line)",
            "type": "textarea",
            "default": "0, 0\n40, 0\n45, 25\n0, 30",
            "shown_when": {
                "shape": "coords"
            }
        }
    ],
    "outputs": [
        {
            "key": "area_sq_m",
            "label": "Area",
            "format": "number"
        },
        {
            "key": "area_sq_ft",
            "label": "Square feet",
            "format": "number"
        },
        {
            "key": "area_sq_yd",
            "label": "Square yards",
            "format": "number"
        },
        {
            "key": "acres",
            "label": "Acres",
            "format": "number"
        },
        {
            "key": "hectares",
            "label": "Hectares",
            "format": "number"
        },
        {
            "key": "perimeter",
            "label": "Perimeter (in the length unit entered)",
            "format": "number"
        }
    ],
    "formula": {
        "text": "Rectangle: L × W;  Triangle (Heron): √(s(s−a)(s−b)(s−c)), s = (a+b+c) ÷ 2;  Four sides: two Heron triangles sharing the diagonal;  Coordinates (shoelace): ½ |Σ (xᵢyᵢ₊₁ − xᵢ₊₁yᵢ)|",
        "variables": {
            "a, b, c": "side lengths of a triangle",
            "xᵢ, yᵢ": "corner coordinates in order around the plot"
        }
    },
    "worked_example": {
        "inputs": {
            "shape": "rectangle",
            "unit": "m",
            "length": "30",
            "width": "20",
            "side_a": "30",
            "side_b": "40",
            "side_c": "50",
            "q_a": "30",
            "q_b": "40",
            "q_c": "32",
            "q_d": "38",
            "q_diag": "50",
            "coords": "0, 0\n40, 0\n45, 25\n0, 30"
        },
        "steps": [
            "Area = 30 m × 20 m = 600 m².",
            "In square feet: 600 ÷ 0.09290304 = 6,458.35 sq ft.",
            "In hectares: 600 ÷ 10,000 = 0.06 ha; in acres: 600 ÷ 4,046.856 = 0.1483 acres."
        ],
        "result": "A 30 m by 20 m plot is 600 m², about 6,458 sq ft or 0.148 acres."
    },
    "interpretation": "For a legal boundary, rely on the surveyed area on the title or plan. This tool is for checking measurements and comparing plots.",
    "assumptions": [
        "The plot is treated as flat; areas are horizontal (plan) areas.",
        "Sides are straight lines between corners."
    ],
    "limitations": [
        "Curved boundaries and sloping ground need a survey; the four-sides method needs the diagonal, because four sides alone do not fix the shape."
    ],
    "rules": null,
    "faqs": [
        {
            "question": "Why do I need a diagonal for a four-sided plot?",
            "answer": "Four side lengths alone can form many different shapes with different areas. The diagonal splits the plot into two triangles whose areas are fixed by their sides."
        },
        {
            "question": "How do I get coordinates?",
            "answer": "Pick one corner as 0, 0 and measure each other corner’s distance east (x) and north (y) from it, or read them from a site plan or GPS survey in metres."
        }
    ],
    "sources": [],
    "related": [
        {
            "name": "Land Area Unit Converter",
            "url": "https://calculators.geekmidst.com/calculators/land-unit-conversion-calculator"
        },
        {
            "name": "Length Converter",
            "url": "https://calculators.geekmidst.com/calculators/length-converter"
        },
        {
            "name": "Concrete Calculator",
            "url": "https://calculators.geekmidst.com/calculators/concrete-calculator"
        }
    ],
    "disclaimer": null,
    "publisher": "GM¹X CalcVerse"
}