|Developed by||3D Industry Forum,
|Initial release||August 2005|
|Latest release||4th edition / June 2007|
|Type of format||File format for 3D computer graphics|
Universal 3D (U3D) is a compressed file format standard for 3D computer graphics data.
The format was defined by a special consortium called 3D Industry Forum that brought together a diverse group of companies and organizations, including Intel, Boeing, HP, Adobe Systems, Bentley Systems, Right Hemisphere and others whose main focus had been the promotional development of 3D graphics for use in various industries, specifically at this time manufacturing as well as construction and industrial plant design. The format was later standardized by Ecma International in August 2005 as ECMA-363.
The goal is a universal standard for three-dimensional data of all kinds, to facilitate data exchange. The consortium promoted also the development of an open source library for facilitating the adoption of the format. The library is also well known for having serious memory management issues.
Editions of U3D 
There are four editions to date.
The first edition is supported by many/all of the various applications mentioned below. It is capable of storing vertex based geometry, color, textures, lighting, bones, and transform based animation.
The second and third editions correct some errata in the first edition, and the third edition also adds the concept of vendor specified blocks. One such block widely deployed is the RHAdobeMesh block, which provides a more compressed alternative to the mesh blocks defined in the first edition. Deep Exploration, 3D PDF Converter for Acrobat Pro and PDF3D-SDK can author this data, and Adobe Acrobat and Reader 8.1 can read this data.
The fourth edition provides definitions for higher order primitives - curved surfaces.
Application support 
PDF with embedded U3D objects can be created by at least the following list of applications:
- Adobe Systems Acrobat Extended allows PDF creation and conversion of various file formats to U3D within the PDF.
- Adobe Systems Acrobat Pro allows PDF creation and embedding of pre-created U3D files.
- tetra4D - 3D PDF Converter allows 3D PDF creation and includes conversion of popular 3D file formats to U3D within the PDF
- Bluebeam Software, Inc. Bluebeam PDF Revu Revu 9 allows PDF creation and embedding of pre-created U3D files.
- Bentley Systems MicroStation allows export of PDF containing U3D.
- Jreality, an open source mathematical visualization package with 3D-PDF and U3D export
- Kubotek KeyCreator allows opening and importing U3D, export of U3D, and export of PDF containing U3D.
- Nemetschek Allplan allows export of PDF containing U3D.
- AVEVA Review allows exportation of 3D models to 3D PDF and U3D formats.
- Vertex G4 CAD allows exportation of 3D models to 3D PDF and U3D formats.
- pdfTeX with the media9 package.
- iText open source Java library allows creation of PDF containing U3D
- SolidWorks allows saving of files to 3D PDF containing U3D.
- 3DVIA Composer allows exportation of 3D models to 3D PDF and U3D formats.
- Siemens PLM Software Process Simulate allows export of U3D files.
- ESKOArtwork "Studio" a Plugin for Adobe Illustrator, allows export of U3D files.
- Okino PolyTrans provides full, bidirectional U3D conversions.
- Pro Engineer Wildfire Allows saving of files to 3D PDF and U3D formats.
- SAP Visual Enterprise Generator from SAP AG allows export of PDF containing U3D.
- Graphisoft ArchiCAD allows export of U3D files.
- PDF3D SDK toolkit generates 3D PDF, U3D (with Right Hemisphere Compression) and PRC (file format).
- Adobe Systems Photoshop CS3, CS4 and CS5 Extended are able to export a 3D Layer as a U3D file.
- Open Inventor SDK by VSG generates 3D PDF, U3D 
- Autodesk Revit using 3D PDF for Revit plugin supports saving of files to 3D PDF using the U3D format.
- Autodesk 3DS Max using 3D PDF for 3DS Max plugin supports saving of files to 3D PDF using the U3D format.
- Autodesk Navisworks using 3D PDF for Navisworks plugin supports saving of files to 3D PDF using the U3D format.
- Autodesk Inventor using 3D PDF for Inventor plugin supports saving of files to 3D PDF using the U3D format.
- Autodesk Maya using 3D PDF for Maya plugin supports saving of files to 3D PDF using the U3D format.
- Autodesk AutoCAD using 3D PDF for AutoCAD plugin supports saving of files to 3D PDF using the U3D format.
U3D files can be imported by at least the following list of applications:
See also 
- ECMA-363: Universal 3D File Format official specifications of the format
- The U3D Sample Software development formerly www.3dif.org
- Embedding interactive 3D object in a PDF using MeshLab and U3D, Visual Computing Group. ISTI CNR. Example of an embedded U3D in a pdf.
- German Tutorial for creating 3DPDF An interactive tutorial about embedding a U3D file into a PDF with Meshlab and Miktex.