# Mime [](https://www.npmjs.com/package/mime) [](https://github.com/broofa/mime/actions/workflows/ci.yml?query=branch%3Amain) An API for MIME type information. - All `mime-db` types - Compact and dependency-free [](https://bundlejs.com/?q=mime) - Full TS support > [!Note] > `mime@4` is now `latest`. If you're upgrading from `mime@3`, note the following: > * `mime@4` is API-compatible with `mime@3`, with ~~one~~ two exceptions: > * Direct imports of `mime` properties [no longer supported](https://github.com/broofa/mime/issues/295) > * `mime.define()` cannot be called on the default `mime` object > * ESM module support is required. [ESM Module FAQ](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c). > * Requires an [ES2020](https://caniuse.com/?search=es2020) or newer runtime > * Built-in Typescript types (`@types/mime` no longer needed) ## Installation ```bash npm install mime ``` ## Quick Start For the full version (800+ MIME types, 1,000+ extensions): ```javascript import mime from 'mime'; mime.getType('txt'); // ⇨ 'text/plain' mime.getExtension('text/plain'); // ⇨ 'txt' ``` ### Lite Version [](https://bundlejs.com/?q=mime/lite) `mime/lite` is a drop-in `mime` replacement, stripped of unofficial ("`prs.*`", "`x-*`", "`vnd.*`") types: ```javascript import mime from 'mime/lite'; ``` ## API ### `mime.getType(pathOrExtension)` Get mime type for the given file path or extension. E.g. ```javascript mime.getType('js'); // ⇨ 'application/javascript' mime.getType('json'); // ⇨ 'application/json' mime.getType('txt'); // ⇨ 'text/plain' mime.getType('dir/text.txt'); // ⇨ 'text/plain' mime.getType('dir\\text.txt'); // ⇨ 'text/plain' mime.getType('.text.txt'); // ⇨ 'text/plain' mime.getType('.txt'); // ⇨ 'text/plain' ``` `null` is returned in cases where an extension is not detected or recognized ```javascript mime.getType('foo/txt'); // ⇨ null mime.getType('bogus_type'); // ⇨ null ``` ### `mime.getExtension(type)` Get file extension for the given mime type. Charset options (often included in Content-Type headers) are ignored. ```javascript mime.getExtension('text/plain'); // ⇨ 'txt' mime.getExtension('application/json'); // ⇨ 'json' mime.getExtension('text/html; charset=utf8'); // ⇨ 'html' ``` ### `mime.getAllExtensions(type)` > [!Note] > New in `mime@4` Get all file extensions for the given mime type. ```javascript --run default mime.getAllExtensions('image/jpeg'); // ⇨ Set(3) { 'jpeg', 'jpg', 'jpe' } ``` ## Custom `Mime` instances The default `mime` objects are immutable. Custom, mutable versions can be created as follows... ### new Mime(type map [, type map, ...]) Create a new, custom mime instance. For example, to create a mutable version of the default `mime` instance: ```javascript import { Mime } from 'mime/lite'; import standardTypes from 'mime/types/standard.js'; import otherTypes from 'mime/types/other.js'; const mime = new Mime(standardTypes, otherTypes); ``` Each argument is passed to the `define()` method, below. For example `new Mime(standardTypes, otherTypes)` is synonomous with `new Mime().define(standardTypes).define(otherTypes)` ### `mime.define(type map [, force = false])` > [!Note] > Only available on custom `Mime` instances Define MIME type -> extensions. Attempting to map a type to an already-defined extension will `throw` unless the `force` argument is set to `true`. ```javascript mime.define({'text/x-abc': ['abc', 'abcd']}); mime.getType('abcd'); // ⇨ 'text/x-abc' mime.getExtension('text/x-abc') // ⇨ 'abc' ``` ## Command Line ### Extension -> type ```bash $ mime scripts/jquery.js application/javascript ``` ### Type -> extension ```bash $ mime -r image/jpeg jpeg ```