Our free and fast tool will convert your 3D U3D (Universal 3D) model files to a standard FBX (Autodesk Filmbox) file that can then be edited further in most popular 3D editing packages or 3D printed without any further processing. Our conversion tool can also batch convert multiple U3D files; up to 200 files at a time can be converted.
To convert your U3D file, click the Upload button above and select the file to convert. Once selected, the file will be converted to a FBX file and will be ready for download shortly afterwards. For more information about the U3D to FBX conversion process, see the conversion information section below.
| Extension | U3D |
| Full Name | Universal 3D |
| Type | 3D Model |
| Mime Type | model/u3d |
| Format | Binary |
| Tools | U3D Converters, 3D Model Voxelizer, Create U3D Animation |
The U3D file is a 3D file format (Universal 3D) developed by a consortium of well-known companies in 2005 with the idea of creating a standardized file format for storing 3D data, including mesh vertices, textures, bones, and effects.
U3D files are binary in nature, containing a block-based structure that, following later revisions, could be extended with custom blocks.
| Extension | FBX |
| Full Name | Autodesk Filmbox |
| Type | 3D Model |
| Mime Type | application/octet-stream |
| Format | Text & Binary |
| Tools | FBX Converters, 3D Model Voxelizer, Create FBX Animation, FBX Asset Extractor, Text to FBX, FBX Viewer |
| Open With | Blender, MeshLab |
The FBX format by AutoDesk was originally developed by Kaydara in the 1990s as a means to store 2D or 3D content with motion data. It has evolved over the years to become a widely used format by 3D modeling applications such as Blender, 3D Studio Max, and others due to its 3D animation capabilities.
The format is used to contain 3D models, which include vertices, faces, and other 3D geometry along with animation data. The format is proprietary; however, there is a publicly available API to use for development purposes. The file contents can be either text or binary, and work has been carried out by the Blender Foundation to document the format.
If your original model file contains texture images and other texture-related data, these will be included in the final FBX file.
Converting from the U3D file format to FBX can be a complex process, and any tool used for this conversion process needs to be able to handle a variety of data conversion tasks as well as identify any defects within the 3D model and fix them. Here we will explain the conversion process used by our tool to accurately convert your U3D file to a valid FBX 3D model. Let's start with the conversion process, which involves the following steps:
In its simplest form, an U3D file is a binary data file containing 3D data such as vertices, faces, normals, and more. When combined, these make up the 3D model you see on your screen.
For more information regarding the U3D file format, please see this great article that goes into a lot of detail explaining the U3D format.
With the U3D file data read, our tool generates an internal representation of the full 3D model and will attempt to fix any geometry issues encountered. Along with repairing any issues with the 3D model, the tool will remove any duplicated vertices and prepare the model for exporting to the FBX format.
With the conversion process entering its final stages, our tool now needs to take the in-memory 3D model we have created in step 2 and convert it to the FBX format.
Yes! Our U3D tool supports full batch conversions. You can upload up to 200 U3D files at a time. Our tool will convert them all as quickly as possible. Once completed, you can either download the FBX files individually or download them all in a single ZIP file.
First click the "Upload..." button, and select your U3D file to upload. You can also drag and drop your file onto the tool. Once your file is selected, you can set any configuration options. When the U3D to FBX conversion has completed, you can download your FBX file straight away.
We aim to process all U3D to FBX conversions as quickly as possible, this usually takes around 5 seconds but can be more for larger more complex files so please be patient.
We aim to create the most accurate conversions with our tools. Our tools are under constant development with new features and improvements being added every week.
Yes, of course! We do not store the U3D file you submit to us. The resulting FBX file, once created, is stored for 4 hours after upload; after this time it is deleted, and the short-term download link will stop working. You can create a long-term download Url with most tools that will ensure the file is retained for 24 hours, allowing you to download the file when convenient. Our tools also come with a Delete button, allowing you to delete the file immediately.
No. All our conversion tools process your U3D file on our dedicated conversion servers, meaning you can use our tools on low-spec computers, laptops, tablets, and mobile devices and receive your converted FBX file quickly.
Yes! Our U3D to FBX tool will run on any system with a modern web browser. No specialist software is needed to run any of our conversion tools.
Yes. Although you can use an Ad Blocker, if you like our U3D conversion tool please consider white-listing our website. When an Ad Blocker is enabled there are some conversion limits and some settings may not be available when using our tools. Processing/conversion and download times will also be longer.
Yes. When you have converted your U3D to FBX, there is a "Feedback" option that you can use to let us know of any issues you encountered when converting your file.
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