MDN wants to talk to developers like you:


The Content-Type entity header is used to indicate the media type of the resource.

In responses, a Content-Type header tells the client what the content type of the returned content actually is. Browsers will do MIME sniffing in some cases and will not necessarily follow the value of this header; to prevent this behavior, the header X-Content-Type-Options can be set to nosniff.

In requests, (such as POST or PUT), the client tells the server what type of data is actually sent.

Header type Entity header
Forbidden header name no
CORS-safelisted response-header yes


Content-Type: text/html; charset=utf-8
Content-Type: multipart/form-data; boundary=something


The MIME type of the resource or the data.
The character encoding standard.
For multipart entities the boundary directive is required, which consists of 1 to 70 characters from a set of characters known to be very robust through email gateways, and not ending with white space. It is used to encapsulate the boundaries of the multiple parts of the message.


Content-Type in HTML forms

In a POST request, resulting from an HTML form submission, the Content-Type of the request is specified by the enctype attribute on the <form> element.

<form action="/" method="post" enctype="multipart/form-data">
  <input type="text" name="description" value="some text">
  <input type="file" name="myFile">
  <button type="submit">Submit</button>

The request looks something like this (less interesting headers are omitted here):

POST /foo HTTP/1.1
Content-Length: 68137
Content-Type: multipart/form-data; boundary=---------------------------974767299852498929531610575

Content-Disposition: form-data; name="description" 

some text
Content-Disposition: form-data; name="myFile"; filename="foo.txt" 
Content-Type: text/plain 

(content of the uploaded file foo.txt)


Specification Title
RFC 7233, section 4.1: Content-Type in multipart Hypertext Transfer Protocol (HTTP/1.1): Range Requests
RFC 7231, section Content-Type Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari Servo
Feature Android Chrome for Android Edge Mobile Firefox for Android IE Mobile Opera Mobile Safari Mobile

See also

Document Tags and Contributors

 Contributors to this page: hutushen222, fscholz, TED-996, teoli, Jeremie
 Last updated by: hutushen222,