What is MIME type "application/unigraphics"?

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

application/unigraphics is a MIME type that identifies files created by Siemens Unigraphics, now known as Siemens NX. These files contain detailed 3D design and engineering data.

They use the file format linked here: PRT. This extension is common for parts made in advanced CAD software.

Store design details in a structured, proprietary format.
Enable seamless data exchange between different CAD systems.
Support engineering analysis and production planning workflows.

This MIME type helps operating systems and applications recognize file content and treat it appropriately. For additional insights, visit the Siemens NX official page.

Associated file extensions

.prt

Usage Examples

HTTP Header

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


    Content-Type: application/unigraphics

HTML

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


    <a href="file.dat" type="application/unigraphics">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', 'application/unigraphics');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.prt

FAQs

What kind of file uses the application/unigraphics MIME type?

The application/unigraphics MIME type is specifically used for Siemens NX (formerly Unigraphics) part files. These files typically use the .prt extension and contain complex 3D geometry, topology, and metadata required for computer-aided design (CAD) and manufacturing.

How do I configure Apache to serve .prt files correctly?

To ensure Apache serves Siemens NX files with the correct headers, add the following line to your .htaccess file or main configuration: AddType application/unigraphics .prt. This prevents the browser from misinterpreting the binary CAD data as plain text.

Can web browsers display application/unigraphics files?

No, standard web browsers like Chrome, Firefox, or Edge cannot natively render application/unigraphics content. When a user navigates to a file with this MIME type, the browser will usually trigger a download dialog so the file can be opened in local CAD software.

What software is required to open this MIME type?

Files served as application/unigraphics require specialized engineering software. The primary application is Siemens NX, though other advanced CAD tools like Solid Edge or dedicated 3D viewers may also support importing this proprietary format.

Are there other MIME types associated with the .prt extension?

Yes, the .prt extension is ambiguous and is also used by PTC Creo (formerly Pro/ENGINEER). While application/unigraphics identifies Siemens files, PTC files might be served as application/pro_eng or generic application/octet-stream. You may need to inspect the file header to distinguish them.

How do I add support for this MIME type in Nginx?

Open your mime.types file (usually located in /etc/nginx/) and add the entry: application/unigraphics prt;. After saving the file, reload the Nginx service to ensure that users downloading .prt files receive the correct Content-Type header.

Why does the file open as random characters in my browser?

If a .prt file displays as "garbage" text, your web server is likely misconfigured and sending a text/plain header by default. You must explicitly configure the server to associate the extension with application/unigraphics to force a file download instead of a text render.

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.