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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 |
Syntax
Content-Type: text/html; charset=utf-8 Content-Type: multipart/form-data; boundary=something
Directives
media-type
- The MIME type of the resource or the data.
- charset
- The character encoding standard.
- boundary
- 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.
Examples
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> </form>
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" ---------------------------974767299852498929531610575 some text ---------------------------974767299852498929531610575 Content-Disposition: form-data; name="myFile"; filename="foo.txt" Content-Type: text/plain (content of the uploaded file foo.txt) ---------------------------974767299852498929531610575
Specifications
Specification | Title |
---|---|
RFC 7233, section 4.1: Content-Type in multipart | Hypertext Transfer Protocol (HTTP/1.1): Range Requests |
RFC 7231, section 3.1.1.5: Content-Type | Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | Servo |
---|---|---|---|---|---|---|---|
Basic Support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
Feature | Android | Chrome for Android | Edge Mobile | Firefox for Android | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|
Basic Support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
See also
Accept
andAccept-Charset
Content-Disposition
206
Partial ContentX-Content-Type-Options