File Conversion
Convert FGB to KML online
Convert FlatGeobuf — a fast, streamable binary format built for large datasets — into Keyhole Markup Language (KML), which is the Google Earth and Google Maps format. Drop your FGB file below, KML is already selected as the output, and download the result. Everything runs in your browser and the cloud; you never install anything.
Upload your file
Drag and drop it into the converter below — no account needed to start.
Convert in the cloud
MapGO detects the format and produces your download in seconds.
Download & keep it
Files are deleted automatically after 48 hours.
Files are deleted automatically after 48 hours. Your files are never shared.
Why convert FGB to KML with MapGO?
Most online converters take one file and hand back one file. MapGO is built on a real geospatial engine, so a single upload can do more:
- Several outputs in one upload — tick KML and any other formats you need; every selected format is delivered from the same file.
- Files up to 5 GB — far beyond the browser-based converters that choke past a few hundred megabytes.
- Reproject while you convert — set a source and target EPSG code and the coordinate system is changed during the conversion, no second tool needed.
- Private by default — files are deleted automatically after 48 hours.
FGB vs KML at a glance
| FGB | KML | |
|---|---|---|
| Typical use | Large datasets streamed to web maps; cloud-native data pipelines | Google Earth / Google My Maps visualisation and sharing placemarks |
| Size on disk | Compact binary with a built-in spatial index | Verbose XML; the zipped KMZ variant shrinks it considerably |
| Attribute support | Full attribute tables | Styling-first — data lives in ExtendedData and is easy to lose |
| Software support | GDAL/QGIS, plus web libraries via the flatgeobuf JS package | Google Earth/Maps and most GIS tools |
| Web-friendliness | Excellent — streams over plain HTTP range requests | Good inside the Google ecosystem; niche elsewhere |
Other ways to convert FGB to KML
You don't need an online tool for this. If you have GDAL installed, one command does it:
ogr2ogr -f "KML" output.kml input.fgbIn QGIS (free): open your FGB via Layer → Add Layer, then right-click the layer → Export → Save Features As… and pick KML as the format.
The MapGO converter above is for when you don't want to install anything, need to convert to several formats at once, or are handling files too large for a desktop machine — drop the file and download the result.
FGB to KML: frequently asked questions
Is the FGB to KML converter free?
Yes — new accounts get free conversion credits to start, and every paid plan converts unlimited files within its size limit. There is nothing to install; the whole FGB-to-KML conversion runs in the cloud.
Is my data kept private?
Conversion is fully automated and your file is never shared. Files are deleted automatically after 48 hours. Download your KML result and it's yours to keep.
What does the KML output contain?
You get a clean Keyhole Markup Language (KML) file with your geometry and attributes preserved, ready to open in the tools that read KML.
Why is the output so much bigger than my .fgb file?
FlatGeobuf is a compact binary format, while text formats like GeoJSON spell everything out — a size increase after conversion is normal and the data is identical. Gzip the text output when serving it and most of the difference disappears.
Will my layer styling show up in Google Earth?
Geometry and attributes convert; symbology does not, because every format stores styling differently. Google Earth applies its default placemark style — restyle inside Google Earth after opening the file.
Can I convert KML back to FGB?
Yes — use our KML to FGB converter for the reverse direction. MapGO supports conversions in both directions between these formats.