Converting GeoJSON to KML turns your JSON features into a Google Earth-ready XML document with placemarks and geometries.
What is GeoJSON?
GeoJSON is an open, JSON-based format for encoding vector geographic features and their attributes, standardized as RFC 7946 by the IETF.
A GeoJSON document is plain UTF-8 JSON built from Feature and FeatureCollection objects, each pairing a geometry (Point, LineString, Polygon, and their Multi* variants, or a GeometryCollection) with a free-form "properties" object. Because it is human-readable text, it works well with version control, text diffing, and any JSON tooling, and it is the de facto interchange format for web maps and JavaScript libraries such as Leaflet, Mapbox GL, and OpenLayers. Unlike Shapefile it imposes no field-name length limit, mixes geometry types freely within one collection, and stores everything in a single file.
What is KML?
KML (Keyhole Markup Language) is an XML-based format for expressing geographic annotation and visualization, adopted as an OGC standard and popularized by Google Earth.
KML describes Placemarks, geometries (points, lines, polygons), and their presentation using an XML tree that also supports folders for organization, rich styling (icons, colors, line widths, fills), balloon descriptions, and ground overlays. It is designed for display and sharing rather than analysis, and is opened natively by Google Earth, Google Maps, and most GIS packages. Because it targets a single global view, it has no concept of reprojection.
Why convert GeoJSON to KML?
KML is the format to reach for when you want data to open directly in Google Earth or Google Maps for presentation and sharing with non-GIS audiences. It preserves feature geometry while adding a visual, browsable structure of placemarks and folders. It is ideal for stakeholder demos where interactivity and a familiar globe view matter more than analysis.
Coordinate systems
Per RFC 7946, coordinates are longitude/latitude in decimal degrees on the WGS84 datum (EPSG:4326), and the specification removed the older "crs" member, so a compliant GeoJSON file is always assumed to be WGS84. Coordinate order is [longitude, latitude], optionally followed by elevation.
KML coordinates are always geographic WGS84 longitude, latitude, and (optionally) altitude in that order; the format has no CRS or projection field, so any data written to KML is expressed in EPSG:4326 by definition.
What to watch out for
- Output is written in WGS84 (EPSG:4326); since KML supports no other CRS, this matches GeoJSON, which is already WGS84.
- GeoJSON properties become placemark attributes or description content rather than a queryable attribute table.
- Rich cartographic styling is not encoded in GeoJSON, so placemarks inherit generic default styling unless styles are added separately.
- Very large FeatureCollections produce verbose XML that is heavier than the equivalent GeoJSON; consider KMZ for smaller downloads.
How to convert GeoJSON to KML
- Drag your GeoJSON file (.geojson, .json) into the converter above, or click to browse.
- Confirm the source is GeoJSON and choose KML as the output format.
- Optionally pick a target coordinate system (EPSG) to reproject.
- Click Convert and download your KML file. Everything runs in your browser.
Frequently asked questions
- Will my attribute data survive the conversion?
- Yes — feature properties are carried over into each placemark, though they appear as KML attributes/description rather than a spreadsheet-style table.
- Does converting change my coordinates?
- No. Both GeoJSON and KML use WGS84 longitude/latitude, so coordinate values pass through unchanged.
- Can I open the result in Google Earth?
- Yes, the .kml opens directly in Google Earth and most GIS applications.