Our free and fast tool will convert your 3D U3D (Universal 3D) model files to a standard GLTF (Graphics Language Transmission Format) 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 GLTF file and will be ready for download shortly afterwards. For more information about the U3D to GLTF 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 | GLTF |
| Full Name | Graphics Language Transmission Format |
| Type | 3D Model |
| Mime Type | model/gltf-binary |
| Format | Text |
| Tools | GLTF Converters, 3D Model Voxelizer, Create GLTF Animation, GLTF Asset Extractor, Text to GLTF, GLTF Viewer |
The GLTF file format, which can also have the GLB file extension depending on whether the content is binary or text, JSON is a 3D file format used to describe 3D worlds and, as such, contains geometric data such as vertices, faces, normals, animations, and other 3D scene-related data.
The format, described by its creators as the "JPEG of 3D", has gained in popularity and is supported by a wide range of 3D modeling applications such as Blender and MeshLab. The GLTF format is an open standard that is maintained by the Khronos Group.
Converting from the U3D file format to GLTF 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 GLTF 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 GLTF 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 GLTF 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 GLTF 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 GLTF conversion has completed, you can download your GLTF file straight away.
We aim to process all U3D to GLTF 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 GLTF 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 GLTF file quickly.
Yes! Our U3D to GLTF 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 GLTF, 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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