What is MIME type "model/vnd.usdz+zip"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

model/vnd.usdz+zip is a MIME type for 3D model files. It marks files that use a zipped archive to bundle all 3D scene data.

This format is common in augmented reality workflows. It lets a single file package detailed 3D assets, like textures, animations, and geometry. The use of zip compression makes these files easier to distribute and load.

Main Use: Delivering 3D models for AR experiences, especially on Apple devices.
Other Uses: Storing and transferring complex model data with associated resources.
Functionality: Ensures that software handling 3D content can unzip and render the model correctly.

Files with this MIME type usually have the extension USDZ.

For more details on how this file type supports AR and 3D applications, check out Apple AR Quick Look.

Associated file extensions

.usdz

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: model/vnd.usdz+zip

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="model/vnd.usdz+zip">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'model/vnd.usdz+zip');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.usdz

FAQs

How do I configure my web server to serve USDZ files correctly?

To ensure AR Quick Look works on iOS devices, your server must send the correct Content-Type header. For Apache, add AddType model/vnd.usdz+zip .usdz to your .htaccess file. For Nginx, add model/vnd.usdz+zip usdz; inside your mime.types file or types block.

Why isn't my USDZ file opening in AR on iPhone?

The most common issue is the server sending the wrong MIME type, such as application/octet-stream or application/zip. Apple devices require the specific header model/vnd.usdz+zip to automatically trigger the AR viewer. You should also ensure the file is a valid, uncompressed zip archive.

What is the difference between USDZ and GLB?

While both are single-file 3D formats, USDZ is the standard for Apple's AR ecosystem (iOS/macOS), whereas GLB (using model/gltf-binary) is the standard for Android and general web usage. Developers often host both versions and serve the correct one based on the user's operating system.

Does model/vnd.usdz+zip imply compression?

Technically, the file is a ZIP container, but the USDZ specification requires that the data inside be stored without compression (Store method). This allows the 3D engine to read data directly from the file without using memory and CPU to decompress it first, which is critical for mobile AR performance.

Can I open USDZ files on Windows or Android?

Native support is primarily found on Apple devices. On Android, you usually need to convert the file to a GLB file. On Windows, you can view these files using select tools like Adobe Aero or specific 3D viewers that support the Pixar USD standard.

Is model/usd interchangeable with model/vnd.usdz+zip?

No. model/usd usually refers to the uncompressed text or binary USD files. The model/vnd.usdz+zip type is specific to the packaged, archive format used for distribution. Browsers treat them differently, so always use the correct MIME type for .usdz files.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.