HTML <button> Tag

The HTML <button> tag is used for creating a button control in an HTML document.

A <button> element enables the user to submit forms and interact with the document by clicking on the button.

Although this tag is often nested inside a <form> element, this is not a requirement. It can also be linked to a form elsewhere in the document with the form attribute. It can also be used as a standalone control (i.e. without being associated with any <form> elements).

Syntax

The <button> tag is written as <button></button> with its contents between the start and end tag. The contents act as the button's label (i.e. anything written between the start and end tag is displayed on the button). The <button> element accepts a number of attributes that enable you to customize the button's appearance, behavior and more. See below for a full list of attributes that can be used with the <button> tag.

Here's an example of the basic syntax for presenting a <button> element:

Examples

Basic tag usage

Here we use a standalone button (i.e. not attached to a form). We keep things simple by using JavaScript to display an alert box when the user clicks on the button.

<button onclick="JavaScript:alert('Well done!')">Click Me!</button>

Button Nested within a Form

Here we nest the button within a <form> element, which makes the button part of the form.

<form action="/html_5/tags/html_form_tag_action.cfm" method="get" target="_blank">
First name:
<input type="text" name="first_name" maxlength="100">
<br />
Last name:
<input type="text" name="last_name" maxlength="100">
<button type="submit">Submit</button>
</form>

Button Associated to a Form

Here we associate the button to a <form> element by using the form attribute (i.e. we insert the form id as the value). By doing this, we don't need to nest the <button> element inside the <form> element.

<form action="/html_5/tags/html_form_tag_action.cfm" method="get" target="_blank" id="my_form">
First name:
<input type="text" name="first_name" maxlength="100">
<br />
Last name:
<input type="text" name="last_name" maxlength="100">
</form>
<p>Other content...</p>
<button type="submit" form="my_form">Submit</button>

About Form-Associated Elements

Some HTML elements can have a "form owner". This means that the element is associated with the form and it can be used as though it was part of that form. This can be handy if you have one or more forms on a page and the element is not nested within any of them.

The following HTML elements are "form-associated elements":

button
fieldset
input
keygen
label
object
output
select
textarea
img

The ability to associate a form control with a form can overcome the lack of support for nested <form> elements. Although nested <form> elements are not supported in the HTML specification, it is possible that a script could manipulate the DOM in a way that results in nested <form> elements. The HTML5 specification acknowledges this situation and appears to make allowances for it, while warning about the non-conformance of nested <form> elements.

Button with an Image

You can include an <img> element inside your <button> element to display the image on the button. You can still add text to the button, resulting in a combination of image and text.

Like this:

<button onclick="JavaScript:alert('You will love this book!')">
<img src="/pix/web_graphics/free_website_graphics/icons/books/book13.gif" alt="Read book">
<br>Read Book!</button>

Attributes

Attributes can be added to an HTML element to provide more information about how the element should appear or behave.

There are 3 kinds of attributes that you can add to your HTML tags: Element-specific, global, and event handler content attributes.

The <button> element accepts the following attributes.

Element-Specific Attributes

This table shows the attributes that are specific to the <button> tag/element.

Attribute	Description
autofocus	Automatically gives focus to this control when the page loads. This allows the user to start using the control without having to select it first. There must not be more than one element in the document with the autofocus attribute specified. This is a boolean attribute. If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute's canonical name, with no leading or trailing whitespace (i.e. either `autofocus` or `autofocus="autofocus"`). Possible values: [Empty string] autofocus
disabled	Disables the control. Therefore, if the user tries to use the control, nothing will happen. This is a boolean attribute. If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute's canonical name, with no leading or trailing whitespace (i.e. either `disabled` or `disabled="disabled"`). Possible values: [Empty string] disabled
form	Specifies the ID of a form to which this control belongs. Possible values: [The ID of a form element in the element's owner `Document`]
formaction	Specifies the URL of the file that will process the control when submitted.
formenctype	Specifies the content type used to encode the form data set when it's submitted to the server. Possible values: `application/x-www-form-urlencoded` (default) `multipart/form-data` (use this when uploading files) `text/plain` (use this when uploading files)
formmethod	Specifies the HTTP method to use when the control is submitted. Possible values: `get` (the form data is appended to the URL when submitted) `post` (the form data is not appended to the URL) `dialog` (Closes the dialog box in which the form finds itself, if any, and otherwise does not submit.)
formnovalidate	Specifies that the form is not to be validated during submission. This is a boolean attribute. If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute's canonical name, with no leading or trailing whitespace (i.e. either `novalidate` or `novalidate="novalidate"`). Possible values: [Empty string] novalidate
formtarget	Specifies the browsing context to load the destination indicated in the `action` attribute. Possible values: `_blank` `_self` `_top` `_parent`
menu	If the `type` attribute has a value of `menu`, the `menu` attribute must be provided in order to specify the element's menu. The value must be the ID of a `<menu>` element in the same home subtree whose `type` attribute is in the popup menu state. The `menu` attribute can only be used when the `type` attribute has a value of `menu`.
name	Assigns the name of the control.
type	Specifies the type of button. Possible values: `submit` Submits the form. This is the default value. `reset` Resets the form. `button` Does nothing. You can use JavaScript to make the control actually do something. `menu` Displays a menu. When using this value, you must specify the menu using the `menu` attribute (see above).
value	Assigns an initial value to the control. A button (and its value) is only included in the form submission if the button itself was used to initiate the form submission.

Global Attributes

The following attributes are standard across all HTML5 elements. Therefore, you can use these attributes with the <button> tag , as well as with all other HTML tags.

accesskey
class
contenteditable
contextmenu
dir
draggable
dropzone
hidden
id
inert
itemid
itemprop
itemref
itemscope
itemtype
lang
spellcheck
style
tabindex
title
translate

For a full explanation of these attributes, see HTML 5 global attributes.

Event Handler Content Attributes

Event handler content attributes enable you to invoke a script from within your HTML. The script is invoked when a certain "event" occurs. Each event handler content attribute deals with a different event.

Below are the standard HTML5 event handler content attributes.

Again, you can use any of these with the <button> element, as well as any other HTML5 element.

onabort
oncancel
onblur
oncanplay
oncanplaythrough
onchange
onclick
oncontextmenu
ondblclick
ondrag
ondragend
ondragenter
ondragexit
ondragleave
ondragover
ondragstart
ondrop
ondurationchange
onemptied
onended
onerror
onfocus
onformchange
onforminput
oninput
oninvalid
onkeydown
onkeypress
onkeyup
onload
onloadeddata
onloadedmetadata
onloadstart
onmousedown
onmousemove
onmouseout
onmouseover
onmouseup
onmousewheel
onpause
onplay
onplaying
onprogress
onratechange
onreadystatechange
onscroll
onseeked
onseeking
onselect
onshow
onstalled
onsubmit
onsuspend
ontimeupdate
onvolumechange
onwaiting

For a full explanation of these attributes, see HTML 5 event handler content attributes.

Differences Between HTML 4 & HTML 5

HTML5 introduced the following attributes for the <button> element:

autofocus
form
formaction
formenctype
formmethod
formnovalidate
formtarget

To see more detail on the two versions see HTML5 <button> Tag and HTML4 <button> Tag. Also check out the links to the official specifications below.

Template

Here's a template for the <button> tag with all available attributes for the tag (based on HTML5). These are grouped into attribute types, each type separated by a space. In many cases, you will probably only need one or two (if any) attributes. Simply remove the attributes you don't need.

For more information on attributes for this tag, see HTML5 <button> Tag and HTML4 <button> Tag.

Tag Details

For more details about the <button> tag, see HTML5 <button> Tag and HTML4 <button> Tag.

Specifications

Here are the official specifications for the <button> element.

HTML5 Specification (W3C)
HTML Living Standard (WHATWG)
Current W3C Draft (the next version that is currently being worked on)
HTML 4 (W3C)

What's the Difference?

W3C creates "snapshot" specifications that don't change once defined. So the HTML5 specification won't change once it becomes an official recommendation. WHATWG on the other hand, develops a "living standard" that is updated on a regular basis. In general, you will probably find that the HTML living standard will be more closely aligned to the current W3C draft than to the HTML5 specification.

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