Convert TopoJSON to GeoJSON
Turn TopoJSON data into GeoJSON — free, instant, and entirely in your browser, with optional reprojection to any of 200+ coordinate systems.
No upload. No account. Your data stays on your machine.
Drop your files here or click to browse.
Shapefile (all parts or .zip), GeoJSON, KML/KMZ, GPKG, GPX, DXF, CSV, TAB and more — files never leave your browser.
About TopoJSON (TopoJSON)
GeoJSON's topology-preserving sibling — shared boundaries stored once, much smaller files.
Worth knowing: Read-only here: we convert from TopoJSON, not to it.
About GeoJSON (GeoJSON)
The web-native vector format — plain JSON, readable by every mapping library and most modern GIS tools. RFC 7946 expects WGS84 coordinates.
Worth knowing: Text-based and verbose for large datasets; RFC 7946 deprecates non-WGS84 CRS metadata.
How the conversion works
- Drop your TopoJSON file above.
- We read it locally with GDAL compiled to WebAssembly — nothing is uploaded.
- Optionally pick an output coordinate system; official datum grids are applied automatically.
- Download your GeoJSON result, with a transformation report showing exactly what was done.