How do I pull geospatial data from an API?

Pulling geospatial data from an API is usually the same as pulling any other API data, with a few extra things to watch for: geometry format, coordinates/reference system, and pagination/filtering by area.

1) Find the API endpoint

Look for documentation that tells you:

• the base URL
• the endpoint for spatial features (e.g. /locations, /features, /parcels)
• required authentication (API key, OAuth token, etc.)

2) Request data in a geospatial format

Common geospatial response formats:

• GeoJSON: easiest for web and Python
• JSON with lat/lon fields
• WKT/WKB
• Esri REST JSON
• CSV with columns like latitude, longitude

If the API supports it, request GeoJSON or a similar geometry-friendly format.

Example request

curl "https://api.example.com/features?bbox=-122.6,37.6,-122.3,37.9" \
  -H "Authorization: Bearer YOUR_TOKEN"

3) Use spatial filters if available

Many APIs let you filter by:

• bounding box (bbox)
• radius / distance
• polygon
• city/state/region
• viewport extent

This is important because geospatial datasets can be large.

4) Handle pagination

If there are many features, the API may return results in pages:

• page
• limit / offset
• next cursor token

Always loop until all pages are collected.

5) Parse the geometry

If you get GeoJSON, you can load it into GIS tools or Python libraries directly.

Python example: GeoJSON response

import requests
import geopandas as gpd
from shapely.geometry import shape

url = "https://api.example.com/features"
headers = {"Authorization": "Bearer YOUR_TOKEN"}
params = {"bbox": "-122.6,37.6,-122.3,37.9"}

resp = requests.get(url, headers=headers, params=params)
resp.raise_for_status()
data = resp.json()

# If response is a GeoJSON FeatureCollection
gdf = gpd.GeoDataFrame.from_features(data["features"])
print(gdf.head())

6) Convert to a GIS-friendly format if needed

You can save to:

• GeoPackage (.gpkg)
• Shapefile (.shp)
• GeoJSON
• PostGIS

Example:

gdf.to_file("features.gpkg", layer="features", driver="GPKG")

7) Check coordinate reference system (CRS)

Many APIs return coordinates in:

• WGS84 / EPSG:4326 (lon/lat)
• or a projected CRS

If needed, reproject:

gdf = gdf.set_crs("EPSG:4326")
gdf = gdf.to_crs("EPSG:3857")

8) Watch for common pitfalls

• Coordinates reversed: GeoJSON uses [longitude, latitude]
• Missing CRS info
• Rate limits
• Invalid geometry
• Large payloads
• Different geometry types: Point, LineString, Polygon, MultiPolygon

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Simple “recipe”

1. Read API docs
2. Authenticate
3. Request spatial data with bbox/filters
4. Parse JSON/GeoJSON
5. Convert to GeoPandas/Shapely/PostGIS
6. Reproject if needed
7. Save/use the data

If you want, I can show you:

• a Python example for a specific API
• how to pull from ArcGIS REST, Overpass, or GeoJSON APIs
• how to load the result into PostGIS or QGIS