POST

The HTTP POST method sends data to the server. The type of the body of the request is indicated by the Content-Type header.

A POST request is typically sent via an HTML form and results in a change on the server. In this case, the content type is selected by putting the adequate string in the enctype attribute of the <form> element or the formenctype attribute of the <input> or <button> elements:

• application/x-www-form-urlencoded: the values are encoded in key-value tuples separated by '&', with a '=' between the key and the value. Non-alphanumeric characters are percent encoded: this is the reason why this type is not suitable to use with binary data (use application/form-data instead)
• application/form-data
• text/plain

When the POST request is sent via another method that an HTML form, like via an XMLHttpRequest, the body can take any type. As described in the HTTP 1.1 specification, POST is designed to allow a uniform method to cover the following functions:

• Annotation of existing resources
• Posting a message to a bulletin board, newsgroup, mailing list, or similar group of articles;
• Providing a block of data, such as the result of submitting a form, to a data-handling process;
• Extending a database through an append operation.

Request has body	Yes
Successful response has body	Yes
Safe	No
Idempotent	No
Cacheable	Only if freshness information is included
Allowed in HTML forms	Yes

Syntax

POST /index.html

Example

A simple form using the default application/x-www-form-urlencoded content type:

POST / HTTP/1.1
Host: foo.com
Content-Type: application/x-www-form-urlencoded
Content-Length: 13

say=Hi&to=Mom

A form using the multipart/form-data content type:

POST /test.html HTTP/1.1 
Host: example.org 
Content-Type: multipart/form-data;boundary="boundary" 

--boundary 
Content-Disposition: form-data; name="field1" 

value1 
--boundary 
Content-Disposition: form-data; name="field2"; filename="example.txt" 

value2

Specifications

Specification	Title
RFC 7231, section 4.3.3: POST	Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Browser compatibility

See also

• Content-Type
• Content-Disposition