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|Full name||GeoJSON, Version 1.0 (2008)|
This format description is for the first version of GeoSON, published by a group of individuals in January 2008 and describing itself as GeoJSON, Version 1.0. GeoJSON was steadily adopted and implemented and soon played an important role in many spatial database products, web APIs, and open data platforms. Implementers demanded formal standardization and improvements in the specification. In 2015, an IETF (Internet Engineering Task Force) Working Group was chartered to specify the format more precisely and serve as a better guide for implementers. See IETF Geographic JSON Working Group Charter. The working group published RFC 7946 in August 2016 as an IETF Proposed Standard. At the same time, the 2008 GeoJSON specification was declared obsolete. The format defined in RFC 7946, which is not yet described separately on this website, is based closely on the 2008 version, but does have a few changes aimed at more reliable interoperability. In this description, any statement that applies only to the 2008 version, will use the name GeoJSON_2008 to make that explicit.
A complete GeoJSON data structure is always a single JSON object consisting of a collection of name/value pairs, known as members. The GeoJSON specification imposes additional constraints to define a GeoJSON object:
|Production phase||A JSON-based interchange format for geospatial data, typically used during data collection or to transmit selected structured data to a system that will further manipulate the data and/or present it to end users.|
|Relationship to other formats|
|Has extension||TopoJSON, describes lines and polygons in terms of shared arcs. Not described separately on this resource at this time.|
|Has later version||GeoJSON Format as specified in RFC 7946, not separately described on this website.|
|LC experience or existing holdings|
|LC preference||The Library of Congress Recommended Formats Statement (RFS) includes GeoJSON as an acceptable format for Geographic Information System (GIS) - Vector images.|
|Disclosure||Openly documented. Developed by a group of individuals in 2008 and published at geojson.org. Published as an Internet Draft in January 2014.|
The GeoJSON format was rapidly adopted for web applications involving mapping. The GeoJSON wiki had a page listing GeoJSON users (last updated in 2013). The remaining discussion of adoption here dates from 2014. The compilers of this resource have not attempted to determine the relative adoption of the different versions of GeoJSON. Comments welcome.
GeoJSON was used for defining geographic coverage for apps that used Apple's MapKit, starting with iOS 7 (released in September 2013). See instructions for Providing Directions in OS X v10.9 and iOS 7.0. The GeoJSON_2008 format was used by the Maps app and the App Store, to look up apps on the App Store that are capable of providing directions in a target region. See Declaring the Supported Geographic Coverage for Directions.
Although ESRI supports a more complex JSON-based format in its GeoServices REST Specification, various open source projects, including projects by ESRI are developing conversion tools. See Useful References below.
|Licensing and patents||No licensing concerns.|
GeoJSON is based on text using UNICODE and uses a very simple structure. The names used for object types defined in the specification are common English words. GeoJSON is easy for humans to read and write and for machines to parse and generate. UTF-8 is most commonly used, but UTF-16 and UTF-32 are also permitted.
|Technical protection considerations||None|
GeoJSON is based on JSON and inherits the same limitations.
JSON is intended for data interchange and does not employ strong data-typing for numbers or have explicit support for dates. All data is represented as text, with numbers being in base 10 as sequences of digits (including the common exponent notation to express very small or very large numbers). JSON is not appropriate for applications requiring binary data. Boolean values true and false are allowed as values. There is minimal support for coding missing data, using the null value.
|Support for software interfaces (APIs, etc.)||GeoJSON is sufficiently simple that support for reading or writing it has been integrated into almost every GIS system or tool used for applications on the Web.|
|Data documentation (quality, provenance, etc.)||GeoJSON has no built-in support for embedding rich metadata about the dataset as a whole. The Open Geospatial Consortium (OGC) has developed a standard encoding for metadata based on the OGC's Earth Observation Metadata Profile of Observations and Measurements. See https://www.ogc.org/standards/eo-geojson.|
|Beyond normal functionality||None.|
|GIS images and datasets|
The purpose of GeoJSON is to support map generation by providing georeferencing information for features through geospatial positions, and geometry objects constructed from positions. Positions are represented in longitude, latitude, and, optionally altitude, as decimal numbers. The default (strongly recommended but not required in GeoJSON_2008) Coordinate Reference System is WGS84, but alternative systems can be specified. The recommended nomenclature for CRS systems is to use OGC (Open Geospatial Consortium) URNs, for example urn:ogc:def:crs:OGC::CRS84 (for WGS84). EPSG identifiers, originally from the European Petroleum Survey Group and now maintained by the International Association of Oil and Gas Producers (OGP) can also be used. Alternatively, the parameters for a CRS can be linked to by URL.
|Support for GIS metadata||There are no special provisions within GeoJSON for representing richer GIS metadata as defined by FGDC or ISO 19115.|
||The Wikipedia entry for GeoJSON as of October 19, 2013 indicated that the file extension used for JSON was used for GeoJSON.|
|Internet Media Type||application/json
||The Wikipedia entry for GeoJSON as of October 19, 2013 indicated that the MIME type registered with IANA for JSON was used for GeoJSON.|
|Magic numbers||See related format.||See JSON.|
|Pronom PUID||See note.||PRONOM has no entry for GeoJSON as of May 2020|
|Wikidata Title ID||See note.||Wikidata has no Title ID specific to GeoJSON_2008. See https://www.wikidata.org/wiki/Q5533904 for Wikidata information for GeoJSON in general.|