What is MIME type "audio/x-s3m"?

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

audio/x-s3m is a MIME type for module music files. It denotes files that combine audio samples with sequencing data. These files let programs generate multi-channel music from small, efficient packages.

They are built for tracker software that arranges digital sounds. The format supports creative, sample-based compositions often heard in demos and games.

Key uses include:

Module Music Playback – Trackers render dynamic sound patterns and layered audio.
Efficient Audio Composition – The format combines instruments and patterns, saving space.
Creative Sound Design – Widely used in the demo scene and vintage video games.

This MIME type also covers several related module formats such as MOD, FAR, XM, IT, STM, AMF, MED, WOW, DMF, S3M, 669, MTM, MT2, ULT, and OKT.

For further technical details, check the Scream Tracker article on Wikipedia.

Associated file extensions

.mod, .far, .xm, .it, .stm, .amf, .med, .wow, .dmf, .s3m, .669, .mtm, .mt2, .ult, .okt

Usage Examples

HTTP Header

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


    Content-Type: audio/x-s3m

HTML

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


    <a href="file.dat" type="audio/x-s3m">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', 'audio/x-s3m');
      res.end('Content here');
    }).listen(3000);

Associated file extensions

.mod, .far, .xm, .it, .stm, .amf, .med, .wow, .dmf, .s3m, .669, .mtm, .mt2, .ult, .okt

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.