4.10.5.1 States of the type attribute
4.10.5.1.1 Hidden state (type=hidden)

The input element represents a value that is not intended to be examined or manipulated by the user.

If the name attribute is present and has a value that is a case-sensitive match for the string "_charset_", then the element's value attribute must be omitted.

The value IDL attribute applies to this element and is in mode default.

The following content attributes must not be specified and do not apply to the element: accept, alt, autocomplete, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, required, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input and change events do not apply.

4.10.5.1.2 Text (type=text) state and Search state (type=search)

The input element represents a one line plain text edit control for the element's value.

The difference between the Text state and the Search state is primarily stylistic: on platforms where search fields are distinguished from regular text fields, the Search state might result in an appearance consistent with the platform's search fields rather than appearing like a regular text field.

The value attribute, if specified, must have a value that contains no U+000A LINE FEED (LF) or U+000D CARRIAGE RETURN (CR) characters.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, dirname, inputmode, list, maxlength, minlength, pattern, placeholder, readonly, required, and size content attributes; list, selectionStart, selectionEnd, selectionDirection, and value IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, formaction, formenctype, formmethod, formnovalidate, formtarget, height, max, min, multiple, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

4.10.5.1.3 Telephone state (type=tel)

The input element represents a control for editing a telephone number given in the element's value.

The value attribute, if specified, must have a value that contains no U+000A LINE FEED (LF) or U+000D CARRIAGE RETURN (CR) characters.

Unlike the URL and E-mail types, the Telephone type does not enforce a particular syntax. This is intentional; in practice, telephone number fields tend to be free-form fields, because there are a wide variety of valid phone numbers. Systems that need to enforce a particular format are encouraged to use the pattern attribute or the setCustomValidity() method to hook into the client-side validation mechanism.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, maxlength, minlength, pattern, placeholder, readonly, required, and size content attributes; list, selectionStart, selectionEnd, selectionDirection, and value IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, max, min, multiple, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

4.10.5.1.4 URL state (type=url)

The input element represents a control for editing a single absolute URL given in the element's value.

The value attribute, if specified and not empty, must have a value that is a valid URL potentially surrounded by spaces that is also an absolute URL.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, maxlength, minlength, pattern, placeholder, readonly, required, and size content attributes; list, selectionStart, selectionEnd, selectionDirection, and value IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, max, min, multiple, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

If a document contained the following markup:

<input type="url" name="location" list="urls">
<datalist id="urls">
 <option label="MIME: Format of Internet Message Bodies" value="http://tools.ietf.org/html/rfc2045">
 <option label="HTML 4.01 Specification" value="http://www.w3.org/TR/html4/">
 <option label="Form Controls" value="http://www.w3.org/TR/xforms/slice8.html#ui-commonelems-hint">
 <option label="Scalable Vector Graphics (SVG) 1.1 Specification" value="http://www.w3.org/TR/SVG/">
 <option label="Feature Sets - SVG 1.1 - 20030114" value="http://www.w3.org/TR/SVG/feature.html">
 <option label="The Single UNIX Specification, Version 3" value="http://www.unix-systems.org/version3/">
</datalist>

...and the user had typed "www.w3", and the user agent had also found that the user had visited http://www.w3.org/Consortium/#membership and http://www.w3.org/TR/XForms/ in the recent past, then the rendering might look like this:

A text box with an icon on the left followed by the text "www.w3" and a cursor, with a drop down button on the right hand side; with, below, a drop down box containing a list of six URLs on the left, with the first four having grayed out labels on the right; and a scroll bar to the right of the drop down box, indicating further values are available.

The first four URLs in this sample consist of the four URLs in the author-specified list that match the text the user has entered, sorted in some UA-defined manner (maybe by how frequently the user refers to those URLs). Note how the UA is using the knowledge that the values are URLs to allow the user to omit the scheme part and perform intelligent matching on the domain name.

The last two URLs (and probably many more, given the scrollbar's indications of more values being available) are the matches from the user agent's session history data. This data is not made available to the page DOM. In this particular case, the UA has no titles to provide for those values.

4.10.5.1.5 E-mail state (type=email)

How the E-mail state operates depends on whether the multiple attribute is specified or not.

When the multiple attribute is not specified on the element

The input element represents a control for editing an e-mail address given in the element's value.

The value attribute, if specified and not empty, must have a value that is a single valid e-mail address.

When the multiple attribute is specified on the element

The input element represents a control for adding, removing, and editing the e-mail addresses given in the element's values.

The value attribute, if specified, must have a value that is a valid e-mail address list.

A valid e-mail address is a string that matches the email production of the following ABNF, the character set for which is Unicode. This ABNF implements the extensions described in RFC 1123. [ABNF] [RFC5322] [RFC1034] [RFC1123]

email         = 1*( atext / "." ) "@" label *( "." label )
label         = let-dig [ [ ldh-str ] let-dig ]  ; limited to a length of 63 characters by RFC 1034 section 3.5
atext         = < as defined in RFC 5322 section 3.2.3 >
let-dig       = < as defined in RFC 1034 section 3.5 >
ldh-str       = < as defined in RFC 1034 section 3.5 >

This requirement is a willful violation of RFC 5322, which defines a syntax for e-mail addresses that is simultaneously too strict (before the "@" character), too vague (after the "@" character), and too lax (allowing comments, whitespace characters, and quoted strings in manners unfamiliar to most users) to be of practical use here.

The following JavaScript- and Perl-compatible regular expression is an implementation of the above definition.

/^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$/

A valid e-mail address list is a set of comma-separated tokens, where each token is itself a valid e-mail address.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, maxlength, minlength, multiple, pattern, placeholder, readonly, required, and size content attributes; list and value IDL attributes.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, max, min, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown() and stepUp() methods.

4.10.5.1.6 Password state (type=password)

The input element represents a one line plain text edit control for the element's value. The user agent should obscure the value so that people other than the user cannot see it.

The value attribute, if specified, must have a value that contains no U+000A LINE FEED (LF) or U+000D CARRIAGE RETURN (CR) characters.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, inputmode, maxlength, minlength, pattern, placeholder, readonly, required, and size content attributes; selectionStart, selectionEnd, selectionDirection, and value IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, list, max, min, multiple, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, list, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

4.10.5.1.7 Date and Time state (type=datetime)

The input element represents a control for setting the element's value to a string representing a specific global date and time.

See the introduction section for a discussion of the difference between the input format and submission format for date, time, and number form controls.

The value attribute, if specified and not empty, must have a value that is a valid global date and time string.

The min attribute, if specified, must have a value that is a valid global date and time string. The max attribute, if specified, must have a value that is a valid global date and time string.

The step attribute is expressed in seconds. The default step is 60 seconds.

The Date and Time state (and other date- and time-related states described in subsequent sections) is not intended for the entry of values for which a precise date and time relative to the contemporary calendar cannot be established. For example, it would be inappropriate for the entry of times like "one millisecond after the big bang", "the early part of the Jurassic period", or "a winter around 250 BCE".

For the input of dates before the introduction of the Gregorian calendar, authors are encouraged to not use the Date and Time state (and the other date- and time-related states described in subsequent sections), as user agents are not required to support converting dates and times from earlier periods to the Gregorian calendar, and asking users to do so manually puts an undue burden on users. (This is complicated by the manner in which the Gregorian calendar was phased in, which occurred at different times in different countries, ranging from partway through the 16th century all the way to early in the 20th.) Instead, authors are encouraged to provide fine-grained input controls using the select element and input elements with the Number state.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, readonly, required, and step content attributes; list, value, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, and selectionDirection IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

The following fragment shows part of a calendar application. A user can specify a date and time for a meeting (in his local time zone, probably, though the user agent can allow the user to change that), and since the submitted data includes the time-zone offset, the application can ensure that the meeting is shown at the correct time regardless of the time zones used by all the participants.

<fieldset>
 <legend>Add Meeting</legend>
 <p><label>Meeting name: <input type=text name="meeting.label"></label>
 <p><label>Meeting time: <input type=datetime name="meeting.start"></label>
</fieldset>

Had the application used the datetime-local type instead, the calendar application would have also had to explicitly determine which time zone the user intended.

For events where the precise time is to vary as the user travels (e.g. "celebrate the new year!"), and for recurring events that are to stay at the same time for a specific geographic location even though that location may go in and out of daylight savings time (e.g. "bring the kid to school"), the datetime-local type combined with a select element (or other similar control) to pick the specific geographic location to which to anchor the time would be more appropriate.

4.10.5.1.8 Date state (type=date)

The input element represents a control for setting the element's value to a string representing a specific date.

See the introduction section for a discussion of the difference between the input format and submission format for date, time, and number form controls.

The value attribute, if specified and not empty, must have a value that is a valid date string.

The min attribute, if specified, must have a value that is a valid date string. The max attribute, if specified, must have a value that is a valid date string.

The step attribute is expressed in days. The default step is 1 day.

See the note on historical dates in the Date and Time state section.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, readonly, required, and step content attributes; list, value, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, selectionStart, selectionEnd, and selectionDirection IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

4.10.5.1.9 Month state (type=month)

The input element represents a control for setting the element's value to a string representing a specific month.

See the introduction section for a discussion of the difference between the input format and submission format for date, time, and number form controls.

The value attribute, if specified and not empty, must have a value that is a valid month string.

The min attribute, if specified, must have a value that is a valid month string. The max attribute, if specified, must have a value that is a valid month string.

The step attribute is expressed in months. The default step is 1 month.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, readonly, required, and step content attributes; list, value, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, and selectionDirection IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

4.10.5.1.10 Week state (type=week)

The input element represents a control for setting the element's value to a string representing a specific week.

See the introduction section for a discussion of the difference between the input format and submission format for date, time, and number form controls.

The value attribute, if specified and not empty, must have a value that is a valid week string.

The min attribute, if specified, must have a value that is a valid week string. The max attribute, if specified, must have a value that is a valid week string.

The step attribute is expressed in weeks. The default step is 1 week.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, readonly, required, and step content attributes; list, value, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, and selectionDirection IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

4.10.5.1.11 Time state (type=time)

The input element represents a control for setting the element's value to a string representing a specific time.

See the introduction section for a discussion of the difference between the input format and submission format for date, time, and number form controls.

The value attribute, if specified and not empty, must have a value that is a valid time string.

The min attribute, if specified, must have a value that is a valid time string. The max attribute, if specified, must have a value that is a valid time string.

The step attribute is expressed in seconds. The default step is 60 seconds.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, readonly, required, and step content attributes; list, value, valueAsDate, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, and selectionDirection IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

4.10.5.1.12 Local Date and Time state (type=datetime-local)

The input element represents a control for setting the element's value to a string representing a local date and time, with no time-zone offset information.

See the introduction section for a discussion of the difference between the input format and submission format for date, time, and number form controls.

The value attribute, if specified and not empty, must have a value that is a valid local date and time string.

The min attribute, if specified, must have a value that is a valid local date and time string. The max attribute, if specified, must have a value that is a valid local date and time string.

The step attribute is expressed in seconds. The default step is 60 seconds.

See the note on historical dates in the Date and Time state section.

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, readonly, required, and step content attributes; list, value, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, selectionDirection, and valueAsDate IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

The following example shows part of a flight booking application. The application uses an input element with its type attribute set to datetime-local, and it then interprets the given date and time in the time zone of the selected airport.

<fieldset>
 <legend>Destination</legend>
 <p><label>Airport: <input type=text name=to list=airports></label></p>
 <p><label>Departure time: <input type=datetime-local name=totime step=3600></label></p>
</fieldset>
<datalist id=airports>
 <option value=ATL label="Atlanta">
 <option value=MEM label="Memphis">
 <option value=LHR label="London Heathrow">
 <option value=LAX label="Los Angeles">
 <option value=FRA label="Frankfurt">
</datalist>

If the application instead used the datetime type, then the user would have to work out the time-zone conversions himself, which is clearly not a good user experience!

4.10.5.1.13 Number state (type=number)

The input element represents a control for setting the element's value to a string representing a number.

This specification does not define what user interface user agents are to use; user agent vendors are encouraged to consider what would best serve their users' needs. For example, a user agent in Persian or Arabic markets might support Persian and Arabic numeric input (converting it to the format required for submission as described above). Similarly, a user agent designed for Romans might display the value in Roman numerals rather than in decimal; or (more realistically) a user agent designed for the French market might display the value with apostrophes between thousands and commas before the decimals, and allow the user to enter a value in that manner, internally converting it to the submission format described above.

The value attribute, if specified and not empty, must have a value that is a valid floating-point number.

The min attribute, if specified, must have a value that is a valid floating-point number. The max attribute, if specified, must have a value that is a valid floating-point number.

The default step is 1 (allowing only integers to be selected by the user, unless the step base has a non-integer value).

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, placeholder, readonly, required, and step content attributes; list, value, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, selectionDirection, and valueAsDate IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

Here is an example of using a numeric input control:

<label>How much do you want to charge? $<input type=number min=0 step=0.01 name=price></label>

As described above, a user agent might support numeric input in the user's local format, converting it to the format required for submission as described above. This might include handling grouping separators (as in "872,000,000,000") and various decimal separators (such as "3,99" vs "3.99") or using local digits (such as those in Arabic, Devanagari, Persian, and Thai).

The type=number state is not appropriate for input that happens to only consist of numbers but isn't strictly speaking a number. For example, it would be inappropriate for credit card numbers or US postal codes. A simple way of determining whether to use type=number is to consider whether it would make sense for the input control to have a spinbox interface (e.g. with "up" and "down" arrows). Getting a credit card number wrong by 1 in the last digit isn't a minor mistake, it's as wrong as getting every digit incorrect. So it would not make sense for the user to select a credit card number using "up" and "down" buttons. When a spinbox interface is not appropriate, type=text is probably the right choice (possibly with a pattern attribute).

4.10.5.1.14 Range state (type=range)

The input element represents a control for setting the element's value to a string representing a number, but with the caveat that the exact value is not important, letting UAs provide a simpler interface than they do for the Number state.

The value attribute, if specified, must have a value that is a valid floating-point number.

The min attribute, if specified, must have a value that is a valid floating-point number. The default minimum is 0. The max attribute, if specified, must have a value that is a valid floating-point number. The default maximum is 100.

The default value is the minimum plus half the difference between the minimum and the maximum, unless the maximum is less than the minimum, in which case the default value is the minimum.

The default step is 1 (allowing only integers, unless the min attribute has a non-integer value).

The following common input element content attributes, IDL attributes, and methods apply to the element: autocomplete, list, max, min, and step content attributes; list, value, and valueAsNumber IDL attributes; stepDown() and stepUp() methods.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, maxlength, minlength, multiple, pattern, placeholder, readonly, required, size, src, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, selectionDirection, and valueAsDate IDL attributes; select(), setRangeText(), and setSelectionRange() methods.

Here is an example of a range control using an autocomplete list with the list attribute. This could be useful if there are values along the full range of the control that are especially important, such as preconfigured light levels or typical speed limits in a range control used as a speed control. The following markup fragment:

<input type="range" min="-100" max="100" value="0" step="10" name="power" list="powers">
<datalist id="powers">
 <option value="0">
 <option value="-30">
 <option value="30">
 <option value="++50">
</datalist>

...with the following style sheet applied:

input { height: 75px; width: 49px; background: #D5CCBB; color: black; }

...might render as:

A vertical slider control whose primary color is black and whose background color is beige, with the slider having five tick marks, one long one at each extremity, and three short ones clustered around the midpoint.

Note how the UA determined the orientation of the control from the ratio of the style-sheet-specified height and width properties. The colors were similarly derived from the style sheet. The tick marks, however, were derived from the markup. In particular, the step attribute has not affected the placement of tick marks, the UA deciding to only use the author-specified completion values and then adding longer tick marks at the extremes.

Note also how the invalid value ++50 was completely ignored.

For another example, consider the following markup fragment:

<input name=x type=range min=100 max=700 step=9.09090909 value=509.090909>

A user agent could display in a variety of ways, for instance:

As a dial.

Or, alternatively, for instance:

As a long horizontal slider with tick marks.

The user agent could pick which one to display based on the dimensions given in the style sheet. This would allow it to maintain the same resolution for the tick marks, despite the differences in width.

Finally, here is an example of a range control with two labeled values:

<input type="range" name="a" list="a-values">
<datalist id="a-values">
 <option value="10" label="Low">
 <option value="90" label="High">
</datalist>

With styles that make the control draw vertically, it might look as follows:

A vertical slider control with two tick marks, one near the top labeled 'High', and one near the bottom labeled 'Low'.

4.10.5.1.15 Color state (type=color)

The input element represents a color well control, for setting the element's value to a string representing a simple color.

The value attribute, if specified and not empty, must have a value that is a valid simple color.

The following common input element content attributes and IDL attributes apply to the element: autocomplete and list content attributes; list and value IDL attributes.

The value IDL attribute is in mode value.

The input and change events apply.

The following content attributes must not be specified and do not apply to the element: accept, alt, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, required, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

4.10.5.1.16 Checkbox state (type=checkbox)

The input element represents a two-state control that represents the element's checkedness state. If the element's checkedness state is true, the control represents a positive selection, and if it is false, a negative selection. If the element's indeterminate IDL attribute is set to true, then the control's selection should be obscured as if the control was in a third, indeterminate, state.

The control is never a true tri-state control, even if the element's indeterminate IDL attribute is set to true. The indeterminate IDL attribute only gives the appearance of a third state.

input . indeterminate [ = value ]

When set, overrides the rendering of checkbox controls so that the current value is not visible.

The following common input element content attributes and IDL attributes apply to the element: checked, and required content attributes; checked and value IDL attributes.

The value IDL attribute is in mode default/on.

The change event applies.

The following content attributes must not be specified and do not apply to the element: accept, alt, autocomplete, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input event does not apply.

4.10.5.1.17 Radio Button state (type=radio)

The input element represents a control that, when used in conjunction with other input elements, forms a radio button group in which only one control can have its checkedness state set to true. If the element's checkedness state is true, the control represents the selected control in the group, and if it is false, it indicates a control in the group that is not selected.

The radio button group that contains an input element a also contains all the other input elements b that fulfill all of the following conditions:

A document must not contain an input element whose radio button group contains only that element.

If none of the radio buttons in a radio button group are checked when they are inserted into the document, then they will all be initially unchecked in the interface, until such time as one of them is checked (either by the user or by script).

The following common input element content attributes and IDL attributes apply to the element: checked and required content attributes; checked and value IDL attributes.

The value IDL attribute is in mode default/on.

The change event applies.

The following content attributes must not be specified and do not apply to the element: accept, alt, autocomplete, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input event does not apply.

4.10.5.1.18 File Upload state (type=file)

The input element represents a list of selected files, each file consisting of a file name, a file type, and a file body (the contents of the file).


The accept attribute may be specified to provide user agents with a hint of what file types will be accepted.

If specified, the attribute must consist of a set of comma-separated tokens, each of which must be an ASCII case-insensitive match for one of the following:

The string audio/*
Indicates that sound files are accepted.
The string video/*
Indicates that video files are accepted.
The string image/*
Indicates that image files are accepted.
A valid MIME type with no parameters
Indicates that files of the specified type are accepted.
A string whose first character is a U+002E FULL STOP character (.)
Indicates that files with the specified file extension are accepted.

The tokens must not be ASCII case-insensitive matches for any of the other tokens (i.e. duplicates are not allowed).

User agents may use the value of this attribute to display a more appropriate user interface than a generic file picker. For instance, given the value image/*, a user agent could offer the user the option of using a local camera or selecting a photograph from their photo collection; given the value audio/*, a user agent could offer the user the option of recording a clip using a headset microphone.

Authors are encouraged to specify both any MIME types and any corresponding extensions when looking for data in a specific format.

For example, consider an application that converts Microsoft Word documents to Open Document Format files. Since Microsoft Word documents are described with a wide variety of MIME types and extensions, the site can list several, as follows:

<input type="file" accept=".doc,.docx,.xml,application/msword,application/vnd.openxmlformats-officedocument.wordprocessingml.document">

On platforms that only use file extensions to describe file types, the extensions listed here can be used to filter the allowed documents, while the MIME types can be used with the system's type registration table (mapping MIME types to extensions used by the system), if any, to determine any other extensions to allow. Similarly, on a system that does not have file names or extensions but labels documents with MIME types internally, the MIME types can be used to pick the allowed files, while the extensions can be used if the system has an extension registration table that maps known extensions to MIME types used by the system.

Extensions tend to be ambiguous (e.g. there are an untold number of formats that use the ".dat" extension, and users can typically quite easily rename their files to have a ".doc" extension even if they are not Microsoft Word documents), and MIME types tend to be unreliable (e.g. many formats have no formally registered types, and many formats are in practice labeled using a number of different MIME types). Authors are reminded that, as usual, data received from a client should be treated with caution, as it may not be in an expected format even if the user is not hostile and the user agent fully obeyed the accept attribute's requirements.

For historical reasons, the value IDL attribute prefixes the file name with the string "C:\fakepath\". Some legacy user agents actually included the full path (which was a security vulnerability). As a result of this, obtaining the file name from the value IDL attribute in a backwards-compatible way is non-trivial. The following function extracts the file name in a suitably compatible manner:

function extractFilename(path) {
  if (path.substr(0, 12) == "C:\\fakepath\\")
    return path.substr(12); // modern browser
  var x;
  x = path.lastIndexOf('/');
  if (x >= 0) // Unix-based path
    return path.substr(x+1);
  x = path.lastIndexOf('\\');
  if (x >= 0) // Windows-based path
    return path.substr(x+1);
  return path; // just the file name
}

This can be used as follows:

<p><input type=file name=image onchange="updateFilename(this.value)"></p>
<p>The name of the file you picked is: <span id="filename">(none)</span></p>
<script>
 function updateFilename(path) {
   var name = extractFilename(path);
   document.getElementById('filename').textContent = name;
 }
</script>

The following common input element content attributes and IDL attributes apply to the element: accept, multiple, and required content attributes; files and value IDL attributes.

The value IDL attribute is in mode filename.

The change event applies.

The following content attributes must not be specified and do not apply to the element: alt, autocomplete, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, minlength, pattern, placeholder, readonly, size, src, step, and width.

The element's value attribute must be omitted.

The following IDL attributes and methods do not apply to the element: checked, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input event does not apply.

4.10.5.1.19 Submit Button state (type=submit)

The input element represents a button that, when activated, submits the form. The element is a button, specifically a submit button. (This is a fingerprinting vector.)

The formaction, formenctype, formmethod, formnovalidate, and formtarget attributes are attributes for form submission.

The formnovalidate attribute can be used to make submit buttons that do not trigger the constraint validation.

The following common input element content attributes and IDL attributes apply to the element: formaction, formenctype, formmethod, formnovalidate, and formtarget content attributes; value IDL attribute.

The value IDL attribute is in mode default.

The following content attributes must not be specified and do not apply to the element: accept, alt, autocomplete, checked, dirname, height, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, required, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input and change events do not apply.

4.10.5.1.20 Image Button state (type=image)

The input element represents either an image from which a user can select a coordinate and submit the form, or alternatively a button from which the user can submit the form. The element is a button, specifically a submit button.

The coordinate is sent to the server during form submission by sending two entries for the element, derived from the name of the control but with ".x" and ".y" appended to the name with the x and y components of the coordinate respectively.


The image is given by the src attribute. The src attribute must be present, and must contain a valid non-empty URL potentially surrounded by spaces referencing a non-interactive, optionally animated, image resource that is neither paged nor scripted.

The alt attribute provides the textual label for the button for users and user agents who cannot use the image. The alt attribute must be present, and must contain a non-empty string giving the label that would be appropriate for an equivalent button if the image was unavailable.

The input element supports dimension attributes.

The formaction, formenctype, formmethod, formnovalidate, and formtarget attributes are attributes for form submission.

image . width [ = value ]
image . height [ = value ]

These attributes return the actual rendered dimensions of the image, or zero if the dimensions are not known.

They can be set, to change the corresponding content attributes.

The following common input element content attributes and IDL attributes apply to the element: alt, formaction, formenctype, formmethod, formnovalidate, formtarget, height, src, and width content attributes; value IDL attribute.

The value IDL attribute is in mode default.

The following content attributes must not be specified and do not apply to the element: accept, autocomplete, checked, dirname, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, required, size, and step.

The element's value attribute must be omitted.

The following IDL attributes and methods do not apply to the element: checked, files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input and change events do not apply.

Many aspects of this state's behavior are similar to the behavior of the img element. Readers are encouraged to read that section, where many of the same requirements are described in more detail.

Take the following form:

<form action="process.cgi">
 <input type=image src=map.png name=where alt="Show location list">
</form>

If the user clicked on the image at coordinate (127,40) then the URL used to submit the form would be "process.cgi?where.x=127&where.y=40".

(In this example, it's assumed that for users who don't see the map, and who instead just see a button labeled "Show location list", clicking the button will cause the server to show a list of locations to pick from instead of the map.)

4.10.5.1.21 Reset Button state (type=reset)

The input element represents a button that, when activated, resets the form. The element is a button. (This is a fingerprinting vector.)

The value IDL attribute applies to this element and is in mode default.

The following content attributes must not be specified and do not apply to the element: accept, alt, autocomplete, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, required, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input and change events do not apply.

4.10.5.1.22 Button state (type=button)

The input element represents a button with no default behavior. A label for the button must be provided in the value attribute, though it may be the empty string. The element is a button.

The value IDL attribute applies to this element and is in mode default.

The following content attributes must not be specified and do not apply to the element: accept, alt, autocomplete, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, minlength, multiple, pattern, placeholder, readonly, required, size, src, step, and width.

The following IDL attributes and methods do not apply to the element: checked, files, list, selectionStart, selectionEnd, selectionDirection, valueAsDate, and valueAsNumber IDL attributes; select(), setRangeText(), setSelectionRange(), stepDown(), and stepUp() methods.

The input and change events do not apply.