What is MIME type "application/xliff+xml"?

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

The MIME type application/xliff+xml labels files based on the XLIFF standard. It uses XML to structure translation data for software localization.

XML-based format: The file stores text segments in XML, which defines both source and target translations.
Translation workflow: It helps exchange and manage translation strings efficiently between tools.
Interoperability: As an open standard, many computer-aided translation and localization tools support it.
Streamlined localization: It organizes context, meaning, and formatting details to speed up the translation process.

Files using this MIME type are recognized by the file extension XLF.

For more detailed information on the XLIFF standard, see the XLIFF documentation.

Associated file extensions

.xlf

Usage Examples

HTTP Header

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


    Content-Type: application/xliff+xml

HTML

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


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

Associated file extensions

.xlf

FAQs

What is the purpose of the application/xliff+xml MIME type?

This MIME type identifies files that adhere to the XLIFF (XML Localization Interchange File Format) standard. It tells software and servers that the file contains structured XML data specifically designed for exchanging translation and localization strings between different tools.

How do I open a file sent as application/xliff+xml?

These files are typically opened with Computer-Aided Translation (CAT) tools like SDL Trados Studio, Poedit, or MemoQ. Since the underlying format is text-based XML, you can also view the raw code using text editors like Notepad++ or Visual Studio Code.

How do I configure Apache or Nginx to serve XLIFF files correctly?

For Apache, add AddType application/xliff+xml .xlf to your .htaccess or config file. For Nginx, add application/xliff+xml xlf; inside the types { } block of your mime.types or nginx.conf file.

Why does my browser download the .xlf file instead of displaying it?

Most web browsers do not have a native rendering engine for XLIFF data, unlike standard HTML or generic XML. When a browser encounters application/xliff+xml, it usually defaults to downloading the file so you can open it with a specialized local application.

Is application/xliff+xml the same as text/xml?

No, although XLIFF files are technically XML, application/xliff+xml is a specific subtype. Using the specific MIME type is preferred because it explicitly informs the receiving application that the content follows the XLIFF schema, enabling specialized processing features.

Are there security risks associated with XLIFF files?

Because XLIFF is based on XML, it can be susceptible to XXE (XML External Entity) attacks if parsed by insecurely configured software. Always ensure your translation management systems and parsers are patched to disable external entity processing when handling untrusted files.

Can I use the .xliff extension instead of .xlf?

Yes, both .xlf and .xliff are common file extensions for this MIME type. While .xlf is the most widely used 3-letter extension, modern systems generally recognize .xliff as valid for application/xliff+xml as well.

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.