How to Find Places in a Custom Polygon

You have a boundary drawn by a user, exported from GIS software, or defined by your application and need matching places inside it. Send the boundary as inline GeoJSON in a Places API POST request with a polygon filter. Use a polyline filter with a buffer when you need a corridor around a line instead.

Task flow: Polygon or MultiPolygon → Places API POST → matching places inside the area.

This guide shows separate requests for restaurants inside an Atlanta polygon and near an Atlanta polyline.

Find places in a polygon

Use a GeoJSON Polygon or MultiPolygon when the enclosed area defines where places should be located.

POST https://api.geoapify.com/v2/places?apiKey=YOUR_API_KEY
Content-Type: application/json

{
  "categories": ["catering.restaurant"],
  "filter": {
    "type": "polygon",
    "geometry": {
      "type": "Polygon",
      "coordinates": [[
        [-84.38456, 33.78971],
        [-84.37394, 33.78971],
        [-84.37394, 33.79783],
        [-84.38456, 33.79783],
        [-84.38456, 33.78971]
      ]]
    },
    "buffer": 0
  },
  "limit": 100,
  "offset": 0
}

This request finds restaurants inside a small boundary near Piedmont Park in Atlanta. A polygon buffer may be from 0 through 100,000 metres. Set it to 0, or omit it, to search only inside the polygon.

Every position uses [longitude, latitude] order. Close each ring by repeating its first position at the end, and include at least three distinct positions. The first ring is the exterior; later rings are holes. A MultiPolygon contains separate polygons with the same ring structure.

The API accepts at most 10,000 source positions, 100 polygon rings, and 102,400 UTF-8 bytes for the geometry value. It validates ring closure and distinct positions, but does not check self-intersections or whether holes lie inside an outer ring. Validate user-drawn or imported geometry before sending it.

Find places near a polyline with a buffer

Use a GeoJSON LineString or MultiLineString when places should be close to a path rather than inside an enclosed area.

POST https://api.geoapify.com/v2/places?apiKey=YOUR_API_KEY
Content-Type: application/json

{
  "categories": ["catering.restaurant"],
  "filter": {
    "type": "polyline",
    "geometry": {
      "type": "LineString",
      "coordinates": [
        [-84.38456, 33.78971],
        [-84.37925, 33.79377],
        [-84.37394, 33.79783]
      ]
    },
    "buffer": 100
  },
  "limit": 100,
  "offset": 0
}

This request finds restaurants within 100 metres of the Atlanta line. Positions use [longitude, latitude] order. The buffer must be greater than 0 and no more than 100,000 metres; omitting it uses the default of 1,000 metres.

The API accepts at most 10,000 source positions and 102,400 UTF-8 bytes for the geometry value. It does not simplify the line or snap it to roads. The buffer measures geographic proximity, not travel distance or time.

Use a polygon filter when the enclosed area matters. A buffered polyline searches only around the line and does not include the whole polygon interior.