Convert CSV to TopoJSON

Convert CSV (.csv) to TopoJSON (.topojson, .json) online for free. Fast, accurate geospatial format conversion with CRS reprojection.

Ready to convert?

Upload your CSV file and get TopoJSON output in seconds.

About CSV

Comma-Separated Values (CSV) files store tabular data with coordinate columns (latitude/longitude or WKT geometry). A simple, universal format supported by virtually all data tools.

Extensions: .csv
Software: Excel, Google Sheets, QGIS, Python/Pandas, R
Limitations: No built-in geometry type — requires coordinate columns. No CRS metadata. No support for complex geometries without WKT.

About TopoJSON

TopoJSON is an extension of GeoJSON that encodes topology, eliminating redundancy and reducing file size. Shared boundaries between features are stored only once.

Extensions: .topojson, .json
Software: D3.js, Mapbox, QGIS, GDAL/OGR, Leaflet
Limitations: Read-only in most GIS software. Requires conversion for editing. Less widely supported than GeoJSON.

How to Convert CSV to TopoJSON

  • Upload your CSV file (.csv)
  • Review detected layers, features, and coordinate system
  • Select TopoJSON as your output format
  • Choose a target coordinate reference system (optional)
  • Click Convert and download your TopoJSON file

Frequently Asked Questions

How do I convert CSV to TopoJSON?

Upload your CSV file to ConvertGeoData, review the detected data, select TopoJSON as the output format, and click Convert. Your converted file will be ready to download in seconds.

Is the CSV to TopoJSON conversion free?

Yes! ConvertGeoData offers free conversions for all users. No account required for basic conversions. Sign up for a Pro or Business plan for higher limits.

Can I change the coordinate system during conversion?

Yes. ConvertGeoData automatically detects your source CRS and lets you reproject to any EPSG coordinate reference system during conversion.

What software can open TopoJSON files?

TopoJSON files can be opened with D3.js, Mapbox, QGIS, GDAL/OGR and more.

Convert CSV to TopoJSON Now

No installation required. Works in your browser.

Stop emailing zip files and hoping for the best.

GeoShare: cloud preview + flexible download for every geospatial file you share. Coming soon to ConvertGeoData.