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Summary
The HTML <form>
element represents a document section that contains interactive controls to submit information to a web server.
It is possible to use the :valid
and :invalid
CSS pseudo-classes to style a <form>
element.
Content categories | Flow content, palpable content |
---|---|
Permitted content | Flow content, but not containing <form> elements |
Tag omission | None, both the starting and ending tag are mandatory. |
Permitted parent elements | Any element that accepts flow content |
DOM interface | HTMLFormElement |
Attributes
This element includes the global attributes.
accept
HTML 4- A comma-separated list of content types that the server accepts.
accept-charset
- A space- or comma-delimited list of character encodings that the server accepts. The browser uses them in the order in which they are listed. The default value, the reserved string
"UNKNOWN"
, indicates the same encoding as that of the document containing the form element.
In previous versions of HTML, the different character encodings could be delimited by spaces or commas. In HTML5, only spaces are allowed as delimiters. action
- The URI of a program that processes the form information. This value can be overridden by a
formaction
attribute on a<button>
or<input>
element. autocapitalize
- This is a nonstandard attribute used by iOS Safari Mobile which controls whether and how the text value for textual form control descendants should be automatically capitalized as it is entered/edited by the user. If the
autocapitalize
attribute is specified on an individual form control descendant, it trumps the form-wideautocapitalize
setting. The non-deprecated values are available in iOS 5 and later. The default value issentences
. Possible values are:none
: Completely disables automatic capitalizationsentences
: Automatically capitalize the first letter of sentences.words
: Automatically capitalize the first letter of words.characters
: Automatically capitalize all characters.on
: Deprecated since iOS 5.off
: Deprecated since iOS 5.
autocomplete
HTML5- Indicates whether input elements can by default have their values automatically completed by the browser. This setting can be overridden by an
autocomplete
attribute on an element belonging to the form. Possible values are:off
: The user must explicitly enter a value into each field for every use, or the document provides its own auto-completion method; the browser does not automatically complete entries.on
: The browser can automatically complete values based on values that the user has previously entered in the form.
-
Note: If you set
autocomplete
tooff
in a form because the document provides its own auto-completion, then you should also setautocomplete
tooff
for each of the form'sinput
elements that the document can auto-complete. For details, see Google Chrome notes. enctype
- When the value of the
method
attribute ispost
, enctype is the MIME type of content that is used to submit the form to the server. Possible values are:application/x-www-form-urlencoded
: The default value if the attribute is not specified.multipart/form-data
: The value used for an<input>
element with thetype
attribute set to "file".text/plain (HTML5)
This value can be overridden by a
formenctype
attribute on a<button>
or<input>
element. method
- The HTTP method that the browser uses to submit the form. Possible values are:
post
: Corresponds to the HTTP POST method ; form data are included in the body of the form and sent to the server.get
: Corresponds to the HTTP GET method; form data are appended to theaction
attribute URI with a '?' as separator, and the resulting URI is sent to the server. Use this method when the form has no side-effects and contains only ASCII characters.
This value can be overridden by a
formmethod
attribute on a<button>
or<input>
element. name
- The name of the form. In HTML 4, its use is deprecated (
id
should be used instead). It must be unique among the forms in a document and not just an empty string in HTML 5. novalidate
HTML5- This Boolean attribute indicates that the form is not to be validated when submitted. If this attribute is not specified (and therefore the form is validated), this default setting can be overridden by a
formnovalidate
attribute on a<button>
or<input>
element belonging to the form. target
- A name or keyword indicating where to display the response that is received after submitting the form. In HTML 4, this is the name/keyword for a frame. In HTML5, it is a name/keyword for a browsing context (for example, tab, window, or inline frame). The following keywords have special meanings:
_self
: Load the response into the same HTML 4 frame (or HTML5 browsing context) as the current one. This value is the default if the attribute is not specified._blank
: Load the response into a new unnamed HTML 4 window or HTML5 browsing context._parent
: Load the response into the HTML 4 frameset parent of the current frame, or HTML5 parent browsing context of the current one. If there is no parent, this option behaves the same way as_self
._top
: HTML 4: Load the response into the full original window, and cancel all other frames. HTML5: Load the response into the top-level browsing context (i.e., the browsing context that is an ancestor of the current one, and has no parent). If there is no parent, this option behaves the same way as_self
.- iframename: The response is displayed in a named
<iframe>
.
HTML5: This value can be overridden by a
formtarget
attribute on a<button>
or<input>
element.
Examples
HTML Content
<!-- Simple form which will send a GET request --> <form action=""> <label for="GET-name">Name:</label> <input id="GET-name" type="text"> <input type="submit" value="Save"> </form> <!-- Simple form which will send a POST request --> <form action="" method="post"> <label for="POST-name">Name:</label> <input id="POST-name" type="text"> <input type="submit" value="Save"> </form> <!-- Form with fieldset, legend, and label --> <form action="" method="post"> <fieldset> <legend>Title</legend> <input type="radio" id="radio"> <label for="radio">Click me</label> </fieldset> </form>
Specifications
Specification | Status | Comment |
---|---|---|
WHATWG HTML Living Standard The definition of '<form>' in that specification. |
Living Standard | |
HTML5 The definition of '<form>' in that specification. |
Recommendation | |
HTML 4.01 Specification The definition of '<form>' in that specification. |
Recommendation | Initial definition |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 1.0[1] | 1.0 (1.7 or earlier) | (Yes) | (Yes) | (Yes) |
novalidate attribute |
1.0 | 4.0 (2.0) | 10 | ? | ? |
Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | (Yes) | 1.0 (1.0) | (Yes) | (Yes) | (Yes) |
novalidate attribute |
? | 4.0 (2.0) | (Yes) | ? | ? |
[1] The Google Chrome UI for auto-complete request varies, depending on whether autocomplete
is set to off
on input
elements as well as their form. Specifically, when a form has autocomplete
set to off
and its input element's autocomplete
field is not set, then if the user asks for autofill suggestions for the input element, Chrome might display a message saying "autocomplete has been disabled for this form." On the other hand, if both the form and the input element have autocomplete
set to off
, the browser will not display that message. For this reason, you should set autocomplete
to off
for each input that has custom auto-completion.
See also
- HTML forms guide
- Other elements that are used for creating forms:
<button>
,<datalist>
,<fieldset>
,<input>
,<keygen>
,<label>
,<legend>
,<meter>
,<optgroup>
,<option>
,<output>
,<progress>
,<select>
,<textarea>
.