Extensible 3D .x3d
VRML’s ISO-standard successor, in XML.
What an .x3d file holds
X3D is the ISO standard that replaced VRML, and it describes a scene as an XML document: a tree of Transform nodes holding Shape nodes, each pairing an Appearance with a geometry node such as IndexedFaceSet, IndexedTriangleSet or a primitive. It is the archival format for a great deal of scientific, medical and museum 3D work, and because it is XML it is one of the few 3D formats you can usefully read in a text editor.
Commonly seen in: Web3D Consortium tooling, scientific visualisation, museum and heritage archives, BlenderX3D.
| Data | Stored in X3D |
|---|---|
| Geometry | Yes |
| Materials and colour | Yes |
| Texture maps | Yes |
| Animation and rigs | No |
| Scene hierarchy | Yes |
| Read here | Yes |
| Written here | Yes |
Tested against a real file
The last sweep loaded ComputerKeyboard.x3d from Assimp test models with its 1 sidecar files through the viewer on this site: 2,020 triangles across 100 meshes and 100 materials, in 1.9 seconds. Every format's result is on the test results page, run 2026-09-08.
What we put in an .x3d file we write
Geometry, normals and per-mesh material colour. Texture images are not written, for the same reason as VRML: X3D references them by filename rather than carrying them.
Files to bring with it
Drop any referenced texture images in alongside the .x3d.
Convert X3D to another format
Every pairing has a page saying what survives the trip.
Convert something else to X3D
Other things to do with an .x3d file
Questions about X3D
How do I open an .x3d file?
Drop it into the viewer on this site and it opens in the browser, with the scene tree, the materials and the mesh statistics. Nothing is uploaded. If you want it in another program instead, convert it to GLB, which almost everything reads.
Is X3D a good format to archive in?
X3D stores geometry, materials and colour, texture maps, scene hierarchy. Anything outside that list will not be in the file at all, so archive the original alongside it if the surfacing or the rig matters.
Does converting X3D lose quality?
Geometry is copied vertex for vertex, so the shape does not degrade. What gets lost is whatever the target format has no field for: convert to STL and the materials go, convert to OBJ and the animation goes. The comparison table on each converter page says exactly which.
Formats that hold the same things
Or go back to the full format reference.