X3D is an XML-based file format for representing 3-D graphics on the Internet. X3D has the the following features:

• Superior application programming interfaces (APIs)
• Extensions to its predecessor, the Virtual Reality Modeling Language (VRML), for example, CAD capabilities, humanoid animation, NURBS, geospatial, etc.
• Ability to encode a scene using an XML syntax in addition to the Open Inventor-like syntax of VRML97
• Support for multi-texture and multi-stage rendering
• Support for shading with normal map and lightmap
• Support for deferred rendering architecture
• Ability to import cascaded shadow mapping (CSM), screen space ambient occlusion (SSAO), as well as real-time environment reflection/lighting
• Lets users benefit from optimizations such as binary space partitioning trees/quadtrees/octtrees or culling in the Extensible 3D Graphics scene

X3D specifies various profiles for different capability levels, which include X3D Interchange, X3D Core, X3D Interactive, X3D Immersive, X3D CADInterchange and X3D Full.

There are plenty of software programs that natively parse and interpret X3D files. These include Blender, a 3-D graphics and animation editor, and Project Wonderland, the Sun Microsystems virtual world client.

Another program called X3D applet works within a browser and shows content in 3-D, making use of OpenGL 3-D graphics technology. X3D applet can display X3D contents in multiple browsers on multiple operating systems.

In the 2000s, various organizations, including Bitmanagement, enhanced the quality level of X3D's virtual effects to match that of DirectX 9.0c, but at the cost of using proprietary solutions. All key features, including game modeling, have already been completed.