Free Online CityJSON Viewer (No Signup)
Also opens DWG, DXF, STEP, IGES, IFC, SKP, STL, OBJ, GLB, FBX, 3DM and other 3D/CAD files. Drop any file on the viewer.
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What Is a CityJSON File?
CityJSON stores the same 3D city model as CityGML in JSON, which makes it smaller and simpler to read and write. A file lists its city objects by id, each with its type (Building, BuildingPart, TINRelief, Road, WaterBody, SolitaryVegetationObject, Bridge and more), its attributes, its parent and children, and its geometries. All vertices are kept in one shared list as integers, turned into real coordinates by a scale and a translation, and every surface can carry its meaning (roof, wall, ground, window, door), a material and a texture. CityJSON is an OGC community standard, and version 2.0 matches the CityGML 3.0 data model.
CityJSONSeq (.city.jsonl) streams a model as lines: a header with the coordinate system, then one feature per line, each a building or another object with its own vertices. The 3D BAG of the Netherlands and many other open datasets are published as CityJSON tiles.
This viewer reads both in your browser and draws each object at its highest level of detail, coloured by its surfaces and materials, with the coordinates recentred so a city tile draws without jitter. The model exports to OBJ, GLB, DXF or STL. City models in XML open in the CityGML viewer.
Who Uses CityJSON Files?
GIS analysts and researchers working with open 3D building data, urban planners, architects who need the surrounding buildings of a site, developers of digital twins and web maps, and anyone who downloads a 3D BAG tile or another CityJSON dataset and wants to see it without setting up cjio, QGIS or Blender plugins.
Common Use Cases
- Look at a 3D BAG tile or another CityJSON download in 3D
- Check the object types, levels of detail and attributes a file holds
- Open a CityJSONSeq stream as one model
- Measure building heights and distances in metres
- Bring the buildings around a site into SketchUp, Rhino or Blender as OBJ, DXF or GLB
- 3D print a neighbourhood by exporting it as STL or 3MF
Features
CityJSON 1.0, 1.1 and 2.0
Files with or without a transform, as .json or .city.json, recognised by their content.
CityJSONSeq Streams
A .city.jsonl stream opens as one model, feature by feature.
Highest Level of Detail
Each object is drawn at its most detailed level; 3D BAG buildings at LOD 2.2.
Every Geometry Type
MultiSurface, CompositeSurface, Solid, MultiSolid, CompositeSolid, lines and geometry templates.
Surfaces and Materials in Colour
Roofs, walls, ground, windows and doors in their own colours, and the file’s material colours.
Grouped by Object Type
One layer per object type, with children under their parents in the object tree.
Textures
Photo textures are drawn when their images are opened with the model.
City-Scale Coordinates
Coordinates are recentred, so a whole tile draws without jitter, in metres.
Export Back to the Grid
DXF, DWG, OBJ and PLY exports carry the original coordinates; GLB, STL and 3MF use local metres.
Nothing Is Uploaded
The file is read and drawn entirely in your browser. No account, no upload, no copy of your model on a server.
Compatibility & Format Notes
Versions: CityJSON 1.0, 1.1 and 2.0, with or without a transform, and CityJSONSeq streams. Files are recognised by their content, so a .json, a .city.json or a renamed file opens, and other JSON files keep opening as text. Geometry types read: MultiSurface, CompositeSurface, Solid, MultiSolid, CompositeSolid, MultiLineString and GeometryInstance with its template; surfaces keep their holes.
Drawing: each object is drawn at its highest level of detail, and a building whose parts are modelled in more detail is drawn by its parts. Semantic surfaces and object types have their own colours, the first material theme keeps its colours, and the first texture theme is drawn when its images are opened with the file or dropped on the viewer afterwards. Objects are grouped by type, one layer each, with children under their parents and attributes kept with each object. Coordinates are read in metres, and DXF, DWG, OBJ and PLY exports put the model back on its original coordinates.
Not drawn: MultiPoint geometry, and the material and texture themes after the first one.
Embed on Your Website
Add this viewer to your own site with a single line of HTML. Click Embed in the toolbar to generate an embed code, or use the snippet below with your own file URL.
Your Files Stay on Your Computer
Your CityJSON files are parsed entirely in your browser. Nothing is uploaded, stored, or shared unless you explicitly click the Share button. Shared files are hosted for 90 days then deleted.
Frequently Asked Questions
▶How do I open a CityJSON file?
Drop the .json, .city.json or .city.jsonl file on the viewer on this page. It reads the model in your browser and shows it in 3D, on any computer or phone, with nothing to install.
▶Does it open 3D BAG tiles?
Yes. 3D BAG tiles store each building as an LOD0 footprint with building parts at LOD 1.2, 1.3 and 2.2; the viewer draws the parts at LOD 2.2. Both the CityJSON tiles and the CityJSONSeq downloads open.
▶Why are my textures missing?
CityJSON names its texture photos as image files beside the model. Open the model together with its images, or drop the images on the viewer after the model has opened, and the textured surfaces are drawn with their photos.
▶Will the exported model line up with my other data?
DXF, DWG, OBJ and PLY exports carry the original coordinates, so they line up with drawings and GIS layers in the same coordinate system. GLB, STL and the other model formats use local metres centred on the model.
▶Is this CityJSON viewer really free?
Yes, completely free. No signup, no watermarks, no file size limits on the viewer (the optional share-link feature has a 100 MB upload cap). Built by Innerscene as a tool for architects, engineers, and designers.
▶Are my files uploaded to a server?
No. All parsing, rendering, and conversion runs in your browser: nothing is uploaded, stored, or transmitted by default. The Share button is the only feature that uploads a file, and only when you explicitly click it.
▶Can I convert to another format?
Yes. Click Export in the toolbar to save as STL (3D printing), OBJ (Wavefront), GLB (glTF binary), or PDF (snapshot of the current view).
▶Can I embed this viewer on my own site?
Yes. Click Embed in the toolbar to generate a one-line <iframe> snippet you can paste into any HTML page. You can choose whether the embed shows the viewer’s toolbar.
CityJSON is an OGC community standard. Innerscene is not affiliated with the OGC or the CityJSON authors.