What is MIME type "text/javascript"?

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

text/javascript is a MIME type used to mark files containing JavaScript code in plain text. It tells browsers and other software that the content should be treated as executable JavaScript, enabling dynamic behavior on web pages.

When you include a script in an HTML page, the browser uses this MIME type to know it must execute the code. This is common with inline scripts or external files loaded with the <script> tag.

The primary use is to run interactive code on websites.
It helps in delivering client-side functionality such as form validations, animations, and interactive user interfaces.
It is also used in various development tools and environments where JavaScript-based configurations or extensions are needed.

Files carrying JavaScript code may have many extensions. For example, files like JS, JSX, MJS, or even those used for JSON with comments like JSONC are tied to this MIME type. These variations support different development approaches and coding environments.

For more detailed technical information about MIME types, you can refer to resources such as MIME Types on MDN or visit the official IANA Media Types page.

Associated file extensions

.json, .js, .es, .pac, .cy, .jsx, .gs, .mjs, .jsonc, .jsm, .jss, .jsb, .sjs, .jsfl, .code-workspace, .frag, .bones, ._js, .cjs, .code-snippets, .es6, .jake, .javascript, .jscad, .jslib, .jspre, .njs, .peggy, .pegjs, .qs, .ssjs, .sublime-build, .sublime-color-scheme, .sublime-commands, .sublime-completions, .sublime-keymap, .sublime-macro, .sublime-menu, .sublime-mousemap, .sublime-project, .sublime-settings, .sublime-theme, .sublime-workspace, .sublime_metrics, .sublime_session, .xsjs, .xsjslib

Usage Examples

HTTP Header

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


    Content-Type: text/javascript

HTML

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


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

Associated file extensions

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.