Add your TOPOJSON file
Drop one or more .topojson files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
TOPOJSON to GEOJSON
Converting a .topojson font to .geojson repackages the same glyphs and metrics for a different delivery target. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop TOPOJSON files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting TopoJSON topology to GeoJSON
Converting a .topojson font to .geojson repackages the same glyphs and metrics for a different delivery target. A .topojson file is a topological encoding of geographic data: shared boundaries are stored once as arcs and referenced by the shapes that use them, with coordinates quantised and delta-encoded. It typically produces files a small fraction the size of the equivalent GeoJSON.
A .geojson file encodes geographic features as JSON: geometries such as Point, LineString and Polygon, each optionally carrying a free-form properties object, usually collected in a FeatureCollection. It is the format web mapping actually runs on. For this route the practical draw is parses with a standard JSON library — no GIS stack required and a fixed coordinate reference system removes a whole class of projection errors — balanced against verbose and large for dense geometry, with no built-in compression, which is worth knowing before you commit a large batch.
Why convert TOPOJSON to GEOJSON?
The practical trigger for this conversion is usually a mismatch: with .topojson, not directly consumable — most tools require conversion to GeoJSON first. Switching to .geojson buys you parses with a standard JSON library — no GIS stack required, which is why it is the better fit for rendering geographic data in Leaflet, Mapbox or OpenLayers. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
TOPOJSON vs GEOJSON at a glance
| Aspect | TopoJSON topology (.topojson) | GeoJSON (.geojson) |
|---|---|---|
| Format type | Text-based — characters and structure, so there is no visual quality loss | Text-based — characters and structure, so there is no visual quality loss |
| How it stores data | shared boundaries are stored once in a top-level arcs array; geometries reference arcs by index | coordinate order is longitude, latitude — the reverse of how people say it, and the single most common source of bugs |
| Strongest at | serving choropleth and boundary maps to a browser with minimal payload | rendering geographic data in Leaflet, Mapbox or OpenLayers |
| Weak spot | not directly consumable — most tools require conversion to GeoJSON first | verbose and large for dense geometry, with no built-in compression |
| Metadata | geometry and per-object properties are preserved. Quantisation means coordinates are reconstructed to the precision the file's transform declares, not to the original source precision | geometry and the properties object are preserved. Styling is not part of the format, so a conversion from KML loses that presentation information rather than GeoJSON dropping it |
Pick GEOJSON as the output
Select .geojson in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if GEOJSON is selectable, the route is real and validated.
Convert on your device
Press Convert. The font tables are parsed and rewritten locally with fonteditor-core; glyph outlines, hinting, and kerning survive the trip.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid GEOJSON file. Outputs keep the original filename with the .geojson extension.
TOPOJSON to GEOJSON questions, answered
Will converting TOPOJSON to GEOJSON lose quality?
There is no visual quality to lose — topojson is text-oriented and geojson is text-oriented, so the question is structural fidelity. Text, ordering, and basic structure are preserved; complex layout, embedded objects, and styling beyond the target's model are simplified.
Is it private to convert TOPOJSON files here?
Yes — the .topojson file is processed inside your browser tab and never uploaded. The font tables are parsed and rewritten locally with fonteditor-core; glyph outlines, hinting, and kerning survive the trip. Close the tab and the file is gone from memory.
Where will the GEOJSON file work?
Read by Leaflet, Mapbox GL, OpenLayers, QGIS, PostGIS, GDAL and GitHub, which renders it inline. Novus Convert parses it locally and converts to GPX, KML, TopoJSON and WKT.
Will the GEOJSON file be bigger or smaller than my TOPOJSON?
It depends on the content: coordinate order is longitude, latitude — the reverse of how people say it, and the single most common source of bugs. Convert one representative file first and compare before batch-processing a large set.
What happens to the metadata in my TOPOJSON file?
In .topojson, geometry and per-object properties are preserved. Quantisation means coordinates are reconstructed to the precision the file's transform declares, not to the original source precision. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.
Can I convert GEOJSON back to TOPOJSON?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .topojson → .geojson → .topojson is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.