GeoJSON to FlatGeobuf
Drop in a GeoJSON file, check it on the input map preview, then click Convert & download to produce a standard, streamable FlatGeobuf (.fgb).
Processing and data safety
Section titled “Processing and data safety”This tool runs entirely in your browser — your files are never uploaded to a server.
Input and output
Section titled “Input and output”- Formats: GeoJSON, FlatGeobuf
- Flow: GeoJSON → FlatGeobuf (.fgb)
How to use
Section titled “How to use”- Drop a .geojson / .json file onto the drop zone — it is parsed and shown on the input map preview, nothing is converted yet.
- Click “Convert & download” to produce the .fgb; if your browser blocks the download, check the download prompt.
- The result area reports feature count and size; amber disclosure lines list fields dropped for being absent from the first feature and fields written as null for type mismatches.
Key details and limits
Section titled “Key details and limits”- Output is index-free standard FlatGeobuf: suited to whole-file downloads and sequential streaming; produce an indexed (random-access) file with ogr2ogr (SPATIAL_INDEX) or the flatgeobuf CLI.
- FeatureCollection top level only; single layer, no reprojection.
- The column set comes from the first feature: extra fields on later features are dropped (amber disclosure in the result area); column types come from the first feature’s values…
Common use cases
Section titled “Common use cases”- Input: drop a .geojson FeatureCollection (points, lines or polygons) — preview first, convert on click.
- Output: a .fgb file download — the result area reports feature count and size.