Convert CityGML to PLY (Free)
Also converts STL, OBJ, GLB, USDZ, 3MF, DAE from the same file.
Runs in your browser. No upload, no signup, nothing to install.
Also from Innerscene: Circadian Lab, a free lighting calculator for room illuminance, melanopic EML, and glare.
How to convert CityGML to PLY
- 1
Open your .gml file
Drag it onto the viewer above, or click "Open a CityGML File". Files up to 200 MB open directly; the parse runs in a worker so the page stays responsive.
- 2
Pick Polygon File Format in the Export menu
Click Export in the toolbar, then PLY (.ply).
- 3
Download
The .ply is written in the browser and saved straight to your downloads folder. No queue, no email, no watermark.
What survives the conversion
A file conversion is a translation, and formats do not carry the same things. Here is exactly what moves from CityGML into PLY, and what does not.
| Geometry | Kept | Both formats store triangle meshes, so the shape transfers directly. |
|---|---|---|
| Colors and materials | Reduced | CityGML can hold material colors and PLY holds per-vertex color, so materials are flattened to that. |
| Textures | Dropped | PLY does not carry texture images, so a textured model arrives in flat material colors. |
| Layers and structure | Dropped | PLY is a single flat body with no layers or named parts. Everything merges into one object. If you need the structure, export to GLB, OBJ, DXF instead. |
| Units and scale | Dropped | PLY stores no unit. Coordinates are written in meters, so set the import unit to meters if the destination asks. |
| Map coordinates | Kept | PLY gets the map coordinates back: easting, northing and height on the CityGML file’s own grid and in its own unit (a survey in US feet stays in US feet), Z up. Data stored in longitude and latitude is projected to its UTM zone, in meters. |
What the PLY writer emits: Binary little-endian PLY with x/y/z and per-vertex RGB, faces for meshes, edges for linework, vertices only for clouds.
The source: CityGML city model (GML / XML) (.gml)
A CityGML 1.0, 2.0 or 3.0 city model: buildings and their parts, terrain, roads, bridges, tunnels, water, vegetation and city furniture, each object at its highest level of detail, with roofs, walls, ground, windows and doors in their own colours, X3D materials and textures, grouped by object type and recentred from its georeferenced coordinates, in metres.
The target: Polygon File Format (.ply)
The scanning and photogrammetry format, and the one interchange format that treats point clouds as first-class.
Opens in: CloudCompare, MeshLab, Blender, Metashape, RealityCapture.
Your file never leaves your computer
Both the CityGML parser and the PLY writer are JavaScript and WebAssembly running in your own browser tab. There is no upload step, no server-side conversion queue, and no copy of your file anywhere but your machine. That matters for drawings under NDA, for client work, and for anything you would not email to a stranger.
Free to Use, No Signup
There are no accounts and no watermarks on this converter. If it saved you time, the one thing we ask is a mention: a post, a link from your blog or course page, or a reply to someone asking how to open a file.
Share it
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Hear about new formats
Occasional emails when the viewer learns a new format or gets a new tool.
Frequently asked questions
▶Is this CityGML to PLY converter free?
Yes. No signup, no watermark, no per-file limit and no paid tier. Innerscene.
▶Is my CityGML file uploaded anywhere?
No. The file is read with the browser file API and converted in the same tab. Nothing is sent to a server unless you explicitly click Share, which is a separate, opt-in feature.
▶Will my colors and materials survive the PLY export?
CityGML can hold material colors and PLY holds per-vertex color, so materials are flattened to that.
▶Do layers and named parts carry into the PLY file?
PLY is a single flat body with no layers or named parts. Everything merges into one object. If you need the structure, export to GLB, OBJ, DXF instead.
▶Will the PLY open at the right size?
PLY stores no unit. Coordinates are written in meters, so set the import unit to meters if the destination asks.
▶How large a CityGML file can I convert?
Up to 200 MB, and the ceiling adapts to how much memory your device reports. The conversion runs on your own hardware, so a desktop with plenty of RAM will handle more than a phone.
▶Can I convert PLY back to CityGML?
Not here. We read CityGML and write PLY, but not the reverse. the universal 3D viewer
▶Which browsers does it work in?
Chrome, Edge, Firefox and Safari, on Windows, macOS, Linux, iOS and Android. No plugin and no extension.
Convert CityGML to something else
Convert something else to PLY
Or start from the universal 3D viewer.