{"openapi":"3.1.0","info":{"title":"Coordinate Systems API","version":"1.0.0","description":"Map projections and coordinate reference systems as an API — the EPSG dataset made queryable. Every CRS, from geographic systems like WGS 84 (the GPS standard, EPSG 4326) to projected ones like Web Mercator (3857), the UTM zones and national grids, has an EPSG code. Search the dataset by name to find the code you need, then resolve any code to its full definition: name, kind (geographic, projected, …), area of use, scope, and — most usefully — the ready-to-paste PROJ.4 string and WKT definition that GIS libraries (GDAL, PROJ, PostGIS, Leaflet, OpenLayers, QGIS, GeoPandas) consume directly. Search comes from the official EPSG Registry maintained by IOGP; the PROJ.4/WKT exports come from epsg.io. A geodesy / coordinate-reference-system resource — distinct from geocoding (addresses to coordinates), geohashing and administrative-boundary APIs. 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EPSG codes look like 4326 (WGS 84 / GPS), 3857 (Web Mercator), 25832 (UTM zone 32N) or 27700 (British National Grid). Search data from the official EPSG Registry (IOGP); PROJ.4/WKT from epsg.io. A geodesy / coordinate-reference-system resource — distinct from geocoding (addresses to coordinates), geohashing and administrative-boundary APIs. 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