mime-types
Advanced tools
The mime-types npm package is a utility for resolving file extensions to MIME types and vice versa. It is based on the mime-db dataset, which is a comprehensive set of MIME type definitions.
Lookup MIME type for a file extension
This feature allows you to find the MIME type for a given file extension. If the extension has a MIME type in the database, it will return it as a string; otherwise, it will return false.
const mime = require('mime-types');
const mimeType = mime.lookup('json'); // 'application/json'Determine the default extension for a MIME type
This feature enables you to find the default file extension for a given MIME type. If the MIME type has an associated extension, it will return it as a string; otherwise, it will return false.
const mime = require('mime-types');
const extension = mime.extension('application/json'); // 'json'Lookup charset for a MIME type
This feature allows you to find the default charset for a given MIME type, which can be useful when setting the 'Content-Type' header in HTTP responses.
const mime = require('mime-types');
const charset = mime.charset('text/markdown'); // 'UTF-8'Content-Type parsing
This feature is used to build a full Content-Type header given a MIME type or extension. It will also append the charset parameter when appropriate.
const mime = require('mime-types');
const contentType = mime.contentType('markdown'); // 'text/markdown; charset=utf-8'The 'mime' package is similar to 'mime-types' and provides MIME type lookup and extension lookup. It differs in that it allows for custom MIME type definitions and has a slightly different API.
The 'file-type' package is used to detect the file type and MIME type of a Buffer/Uint8Array/ArrayBuffer. Unlike 'mime-types', it does not rely on file extensions and can detect the type of binary content.
The ultimate javascript content-type utility.
Similar to node-mime, except:
mime-types simply returns false,
so do var type = mime.lookup('unrecognized') || 'application/octet-stream'.new Mime() business, so you could do var lookup = require('mime-types').lookup..define() functionalityOtherwise, the API is compatible.
$ npm install mime-types
All mime types are based on mime-db, so open a PR there if you'd like to add mime types.
var mime = require('mime-types')
All functions return false if input is invalid or not found.
Lookup the content-type associated with a file.
mime.lookup('json') // 'application/json'
mime.lookup('.md') // 'text/x-markdown'
mime.lookup('file.html') // 'text/html'
mime.lookup('folder/file.js') // 'application/javascript'
mime.lookup('folder/.htaccess') // false
mime.lookup('cats') // false
Create a full content-type header given a content-type or extension.
mime.contentType('markdown') // 'text/x-markdown; charset=utf-8'
mime.contentType('file.json') // 'application/json; charset=utf-8'
// from a full path
mime.contentType(path.extname('/path/to/file.json')) // 'application/json; charset=utf-8'
Get the default extension for a content-type.
mime.extension('application/octet-stream') // 'bin'
Lookup the implied default charset of a content-type.
mime.charset('text/x-markdown') // 'UTF-8'
A map of content-types by extension.
A map of extensions by content-type.
FAQs
The ultimate javascript content-type utility.
The npm package mime-types receives a total of 92,986,171 weekly downloads. As such, mime-types popularity was classified as popular.
We found that mime-types demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 5 open source maintainers collaborating on the project.
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