How to Calculate the Area of a Polygon

Calculate the area of a polygon

You have a GeoJSON Polygon or MultiPolygon and need its surface area for property analysis, coverage reporting, planning, or comparison. The Geometry Operations API area operation returns a geodesic measurement in square meters.

Task flow: Polygon or MultiPolygon → Geometry Operations API → square meters → optional unit conversion.

The operation measures the geometry you send. Validate the polygon first, preserve holes, and union overlapping polygons before measuring total coverage; otherwise the result may be misleading or overlaps may be counted separately.

Measure the polygon

POST https://api.geoapify.com/v1/geometry/operation?apiKey=YOUR_API_KEY
Content-Type: application/json

{
  "operation": "area",
  "polygon": {
    "type": "Polygon",
    "coordinates": [[
      [13.38, 52.50], [13.42, 52.50],
      [13.42, 52.54], [13.38, 52.54],
      [13.38, 52.50]
    ]]
  }
}

{
  "type": "number",
  "data": 12037619.45316684
}

The result is approximately:

• 12,037,619.45 m²;
• 12.04 km² (m² ÷ 1,000,000);
• 1,203.76 hectares (m² ÷ 10,000);
• 4.65 mi² (m² ÷ 2,589,988.11).

Round only for presentation. Keep the original numeric response for calculations, and record which geometry version was measured.