Overpass API JSON

Overpass JSON is the response format of the Overpass API, the query language for OpenStreetMap data. It is compact JSON: an elements array where every object is a node, way or relation with its coordinates, geometry and tags, plus a service meta block. This structure is read directly by OSMnx, the QuickOSM plugin for QGIS, overpass-turbo and dozens of research pipelines.

The format is chosen when OSM is used as a structured dataset: counting objects by tags, assembling a street graph, exporting points of interest into your own script. A ready file instead of a live query removes the two familiar Overpass problems — rate limits and timeouts on large selections — and it also makes the result reproducible: you hold a fixed snapshot of the data.

The exporter synthesizes a response of the same structure from your selection: points become node elements with coordinates, lines and polygons become way elements with a node list and geometry, tags are carried over as they are, and the generator and version are written into meta. Identifiers are issued by us from a separate range so as not to collide with real OSM numbers; the size of a single file is limited to a hundred thousand elements. This is not a live query to Overpass but a compatible replacement for its response.