ST_AsGeoJSON — Return the geometry as a GeoJSON element.


text ST_AsGeoJSON(record feature, text geomcolumnname, integer maxdecimaldigits=9, boolean pretty_bool=false);

text ST_AsGeoJSON(geometry geom, integer maxdecimaldigits=9, integer options=8);

text ST_AsGeoJSON(geography geog, integer maxdecimaldigits=9, integer options=0);


Return the geometry as a GeoJSON "geometry" object, or the row as a GeoJSON "feature" object. (Cf GeoJSON specifications RFC 7946). 2D and 3D Geometries are both supported. GeoJSON only support SFS 1.1 geometry types (no curve support for example).

The maxdecimaldigits argument may be used to reduce the maximum number of decimal places used in output (defaults to 9). If you are using EPSG:4326 and are outputting the geometry only for display, maxdecimaldigits=6 can be a good choice for many maps.

The options argument could be used to add BBOX or CRS in GeoJSON output:

  • 0: means no option

  • 1: GeoJSON BBOX

  • 2: GeoJSON Short CRS (e.g EPSG:4326)

  • 4: GeoJSON Long CRS (e.g urn:ogc:def:crs:EPSG::4326)

  • 8: GeoJSON Short CRS if not EPSG:4326 (default)

Availability: 1.3.4

Availability: 1.5.0 geography support was introduced.

Changed: 2.0.0 support default args and named args.

Changed: 3.0.0 support records as input

Changed: 3.0.0 output SRID if not EPSG:4326.

This function supports 3d and will not drop the z-index.


GeoJSON format is popular among web mapping frameworks.

You can test and view your GeoJSON data online on

To build FeatureCollection:

select json_build_object(
    'type', 'FeatureCollection',
    'features', json_agg(ST_AsGeoJSON(t.*)::json)
from ( values (1, 'one', 'POINT(1 1)'::geometry),
              (2, 'two', 'POINT(2 2)'),
              (3, 'three', 'POINT(3 3)')
     ) as t(id, name, geom);
{"type" : "FeatureCollection", "features" : [{"type": "Feature", "geometry": {"type":"Point","coordinates":[1,1]}, "properties": {"id": 1, "name": "one"}}, {"type": "Feature", "geometry": {"type":"Point","coordinates":[2,2]}, "properties": {"id": 2, "name": "two"}}, {"type": "Feature", "geometry": {"type":"Point","coordinates":[3,3]}, "properties": {"id": 3, "name": "three"}}]}

To get Features as records:

  (1, 'one', 'POINT(1 1)'::geometry),
  (2, 'two', 'POINT(2 2)'),
  (3, 'three', 'POINT(3 3)'))
AS t(id, name, geom);
 {"type": "Feature", "geometry": {"type":"Point","coordinates":[1,1]}, "properties": {"id": 1, "name": "one"}}
 {"type": "Feature", "geometry": {"type":"Point","coordinates":[2,2]}, "properties": {"id": 2, "name": "two"}}
 {"type": "Feature", "geometry": {"type":"Point","coordinates":[3,3]}, "properties": {"id": 3, "name": "three"}}

Don't forget to transform your data to WGS84 longitude, latitude to conform with RFC7946:

SELECT ST_AsGeoJSON(ST_Transform(geom,4326)) from fe_edges limit 1;

(1 row)

You can also use it with 3D geometries:

SELECT ST_AsGeoJSON('LINESTRING(1 2 3, 4 5 6)');

See Also

ST_GeomFromGeoJSON, ST_AsMVT, ST_AsGeobuf