TopoJSON to GeoPackage Converter
Writes every object of a TopoJSON file as a layer into one GeoPackage.
Upload a .topojson or .json file. Every object of the topology becomes a layer of one GeoPackage. GDAL assigns no coordinate system, so the layers come without one.
Drag a file here to convert, or select file
Accepted: .topojson, .json · max. 50 MB
What the converter does
- Each TopoJSON object becomes a layer; the shared arcs are resolved into complete polygons and lines. Quantized TopoJSON (with transform) is decoded.
- TopoJSON carries no coordinate system and GDAL assigns none.
- The GeoPackage layers have no coordinate system; for longitude/latitude data assign EPSG:4326 in your GIS.
- The report below the upload shows layers and features read and written, skipped layers with the reason, GDAL's warnings and the exact commands.
GDAL command the worker runs
The worker lists all objects of the topology (in the test flaechen and punkte).
Tested with
| Test file | Result |
|---|---|
| TopoJSON with 2 objects: flaechen (2 polygons) and punkte (1 point) | 1 GeoPackage with 2 layers, 3 of 3; no coordinate system |
Tested on 24 Sep 2026 with the worker code of this site and GDAL 3.10.3 (conda-forge build on Windows). The worker image runs the Debian build of the same GDAL version; the live worker was not part of these tests.
Limits
- Upload limit: 50 MB per file.
- Each GDAL step may run for up to 240 seconds; a longer run is stopped with an error message.
Frequently Asked Questions
What happens to my file?
Your browser uploads it directly to the GDAL worker on Fly.io (region Frankfurt). The worker converts it in a temporary folder and deletes the folder after sending the result, or immediately if the conversion fails. Files are not stored permanently.