Convert TopoJSON to GeoJSON online for free — right in your browser. No upload, no sign-up, batch conversion, coordinate systems and attributes preserved.
Efficiently convert from TOPOJSON to GEOJSON format
All processing is done locally in your browser
Output standard GEOJSON format
Convert topojson to geojson online for free — right in your browser. No upload, no sign-up, batch conversion, coordinate systems and attributes preserved.
TopoJSON is a GeoJSON extension developed by Mike Bostock that encodes topology to eliminate redundant shared boundaries. Unlike GeoJSON where each polygon independently stores all vertices, TopoJSON uses arcs to share common boundaries between adjacent features, reducing file sizes by over 80%. TopoJSON is particularly suited for rendering large numbers of adjacent areas such as administrative district maps.
GeoJSON is a geospatial data interchange format based on JSON. It can represent Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, and GeometryCollection geometries. Defined by RFC 7946, GeoJSON has become one of the most popular data exchange formats in web GIS. GeoJSON files use WGS84 coordinates and support Feature objects with associated properties and FeatureCollections for organizing multiple features.
TopoJSON files are compact and great for D3, but almost no other tool understands them — Leaflet, Mapbox, QGIS and PostGIS all expect GeoJSON. Converting TopoJSON to GeoJSON rebuilds each polygon from its shared arcs into standalone features with all original properties attached. It is the routine step when taking boundary data out of a D3 project and into any other mapping tool or database.
The topology stores every arc; reconstruction is exact with respect to the quantized coordinates stored in the file.
Yes — the properties object of every geometry is carried over unchanged.
Yes, the delta-encoded, quantized arcs are decoded using the file's own transform block.
Upload your TopoJSON file — drag and drop it onto the page, or browse from your device. You can add several files at once for batch conversion.
The conversion runs automatically in your browser. No upload, no server — your data stays on your device the entire time.
Download the GeoJSON file. Each input produces its own output, ready to use in your GIS, web map, or archive.