What is MIME type "image/jxl"?

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

image/jxl is the MIME type for JPEG XL images. It tells your computer that the file uses the new JPEG XL format. This format is designed to deliver high-quality images while keeping file sizes small.

JPEG XL supports both lossless and lossy compression. It is built to improve on older image formats by offering better detail preservation and efficient compression.

Main use case: Efficient storage and transmission of high-quality images, especially for web and digital photography.
Additional uses: Handling advanced image features such as high dynamic range, wide color gamut, and transparency.
Key fact: Files using this format typically carry the JXL extension, representing the JPEG XL codestream.

Its design makes it practical for modern computing and internet applications. For more technical details, you can visit the official JPEG XL page.

Associated file extensions

.jxl

Usage Examples

HTTP Header

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


    Content-Type: image/jxl

HTML

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


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

Associated file extensions

.jxl

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.