4.10.7 The input element

Categories:
Flow content.
Phrasing content.
If the type attribute is not in the Hidden state: Interactive content.
If the type attribute is not in the Hidden state: Listed, labelable, submittable, and resettable form-associated element.
If the type attribute is in the Hidden state: Listed, submittable, and resettable form-associated element.
If the type attribute is not in the Hidden state: Palpable content.
Contexts in which this element can be used:
Where phrasing content is expected.
Content model:
Empty.
Tag omission in text/html:
No end tag.
Content attributes:
Global attributes
accept — Hint for expected file type in file upload controls
alt — Replacement text for use when images are not available
autocomplete — Hint for form autofill feature
autofocus — Automatically focus the form control when the page is loaded
checked — Whether the command or control is checked
dirname — Name of form field to use for sending the element's directionality in form submission
disabled — Whether the form control is disabled
form — Associates the control with a form element
formaction — URL to use for form submission
formenctype — Form data set encoding type to use for form submission
formmethod — HTTP method to use for form submission
formnovalidate — Bypass form control validation for form submission
formtarget — Browsing context for form submission
height — Vertical dimension
inputmode — Hint for selecting an input modality
list — List of autocomplete options
max — Maximum value
maxlength — Maximum length of value
min — Minimum value
multiple — Whether to allow multiple values
name — Name of form control to use for form submission and in the form.elements API
pattern — Pattern to be matched by the form control's value
placeholder — User-visible label to be placed within the form control
readonly — Whether to allow the value to be edited by the user
required — Whether the control is required for form submission
size — Size of the control
src — Address of the resource
step — Granularity to be matched by the form control's value
type — Type of form control
value — Value of the form control
width — Horizontal dimension
DOM interface:
interface HTMLInputElement : HTMLElement {
           attribute DOMString accept;
           attribute DOMString alt;
           attribute DOMString autocomplete;
           attribute boolean autofocus;
           attribute boolean defaultChecked;
           attribute boolean checked;
           attribute DOMString dirName;
           attribute boolean disabled;
  readonly attribute HTMLFormElement? form;
  readonly attribute FileList? files;
           attribute DOMString formAction;
           attribute DOMString formEnctype;
           attribute DOMString formMethod;
           attribute boolean formNoValidate;
           attribute DOMString formTarget;
           attribute unsigned long height;
           attribute boolean indeterminate;
           attribute DOMString inputMode;
  readonly attribute HTMLElement? list;
           attribute DOMString max;
           attribute long maxLength;
           attribute DOMString min;
           attribute boolean multiple;
           attribute DOMString name;
           attribute DOMString pattern;
           attribute DOMString placeholder;
           attribute boolean readOnly;
           attribute boolean required;
           attribute unsigned long size;
           attribute DOMString src;
           attribute DOMString step;
           attribute DOMString type;
           attribute DOMString defaultValue;
  [TreatNullAs=EmptyString] attribute DOMString value;
           attribute Date? valueAsDate;
           attribute unrestricted double valueAsNumber;
           attribute unsigned long width;

  void stepUp(optional long n = 1);
  void stepDown(optional long n = 1);

  readonly attribute boolean willValidate;
  readonly attribute ValidityState validity;
  readonly attribute DOMString validationMessage;
  boolean checkValidity();
  void setCustomValidity(DOMString error);

  readonly attribute NodeList labels;

  void select();
           attribute unsigned long selectionStart;
           attribute unsigned long selectionEnd;
           attribute DOMString selectionDirection;
  void setRangeText(DOMString replacement);
  void setRangeText(DOMString replacement, unsigned long start, unsigned long end, optional SelectionMode selectionMode);
  void setSelectionRange(unsigned long start, unsigned long end, optional DOMString direction);

  // also has obsolete members
};

The input element represents a typed data field, usually with a form control to allow the user to edit the data.

The type attribute controls the data type (and associated control) of the element. It is an enumerated attribute. The following table lists the keywords and states for the attribute — the keywords in the left column map to the states in the cell in the second column on the same row as the keyword.

Keyword State Data type Control type
hidden Hidden An arbitrary string n/a
text Text Text with no line breaks A text field
search Search Text with no line breaks Search field
tel Telephone Text with no line breaks A text field
url URL An absolute URL A text field
email E-mail An e-mail address or list of e-mail addresses A text field
password Password Text with no line breaks (sensitive information) A text field that obscures data entry
datetime Date and Time A date and time (year, month, day, hour, minute, second, fraction of a second) with the time zone set to UTC A date and time control
date Date A date (year, month, day) with no time zone A date control
month Month A date consisting of a year and a month with no time zone A month control
week Week A date consisting of a week-year number and a week number with no time zone A week control
time Time A time (hour, minute, seconds, fractional seconds) with no time zone A time control
datetime-local Local Date and Time A date and time (year, month, day, hour, minute, second, fraction of a second) with no time zone A date and time control
number Number A numerical value A text field or spinner control
range Range A numerical value, with the extra semantic that the exact value is not important A slider control or similar
color Color An sRGB color with 8-bit red, green, and blue components A color well
checkbox Checkbox A set of zero or more values from a predefined list A checkbox
radio Radio Button An enumerated value A radio button
file File Upload Zero or more files each with a MIME type and optionally a file name A label and a button
submit Submit Button An enumerated value, with the extra semantic that it must be the last value selected and initiates form submission A button
image Image Button A coordinate, relative to a particular image's size, with the extra semantic that it must be the last value selected and initiates form submission Either a clickable image, or a button
reset Reset Button n/a A button
button Button n/a A button

The missing value default is the Text state.

Which of the accept, alt, autocomplete, checked, dirname, formaction, formenctype, formmethod, formnovalidate, formtarget, height, inputmode, list, max, maxlength, min, multiple, pattern, placeholder, readonly, required, size, src, step, and width content attributes, the checked, files, valueAsDate, valueAsNumber, and list IDL attributes, the select() method, the selectionStart, selectionEnd, and selectionDirection, IDL attributes, the setRangeText() and setSelectionRange() methods, the stepUp() and stepDown() methods, and the input and change events apply to an input element depends on the state of its type attribute. The subsections that define each type also clearly define in normative "bookkeeping" sections which of these feature apply, and which do not apply, to each type. The behavior of these features depends on whether they apply or not, as defined in their various sections.

The following table is non-normative and summarizes which of those content attributes, IDL attributes, methods, and events apply to each state:

Hidden Text, Search URL, Telephone E-mail Password Date and Time, Date, Month, Week, Time Local Date and Time Number Range Color Checkbox, Radio Button File Upload Submit Button Image Button Reset Button, Button
Content attributes
accept · · · · · · · · · · · Yes · · ·
alt · · · · · · · · · · · · · Yes ·
autocomplete · Yes Yes Yes Yes Yes Yes Yes Yes Yes · · · · ·
checked · · · · · · · · · · Yes · · · ·
dirname · Yes · · · · · · · · · · · · ·
formaction · · · · · · · · · · · · Yes Yes ·
formenctype · · · · · · · · · · · · Yes Yes ·
formmethod · · · · · · · · · · · · Yes Yes ·
formnovalidate · · · · · · · · · · · · Yes Yes ·
formtarget · · · · · · · · · · · · Yes Yes ·
height · · · · · · · · · · · · · Yes ·
inputmode · Yes · · · · · · · · · · · · ·
list · Yes Yes Yes · Yes Yes Yes Yes Yes · · · · ·
max · · · · · Yes Yes Yes Yes · · · · · ·
maxlength · Yes Yes Yes Yes · · · · · · · · · ·
min · · · · · Yes Yes Yes Yes · · · · · ·
multiple · · · Yes · · · · · · · Yes · · ·
pattern · Yes Yes Yes Yes · · · · · · · · · ·
placeholder · Yes Yes Yes Yes · · Yes · · · · · · ·
readonly · Yes Yes Yes Yes Yes Yes Yes · · · · · · ·
required · Yes Yes Yes Yes Yes Yes Yes · · Yes Yes · · ·
size · Yes Yes Yes Yes · · · · · · · · · ·
src · · · · · · · · · · · · · Yes ·
step · · · · · Yes Yes Yes Yes · · · · · ·
width · · · · · · · · · · · · · Yes ·
IDL attributes and methods
checked · · · · · · · · · · Yes · · · ·
files · · · · · · · · · · · Yes · · ·
value default value value value value value value value value value default/on filename default default default
valueAsDate · · · · · Yes · · · · · · · · ·
valueAsNumber · · · · · Yes Yes Yes Yes · · · · · ·
list · Yes Yes Yes · Yes Yes Yes Yes Yes · · · · ·
select() · Yes Yes · Yes · · · · · · · · · ·
selectionStart · Yes Yes · Yes · · · · · · · · · ·
selectionEnd · Yes Yes · Yes · · · · · · · · · ·
selectionDirection · Yes Yes · Yes · · · · · · · · · ·
setRangeText() · Yes Yes · Yes · · · · · · · · · ·
setSelectionRange() · Yes Yes · Yes · · · · · · · · · ·
stepDown() · · · · · Yes Yes Yes Yes · · · · · ·
stepUp() · · · · · Yes Yes Yes Yes · · · · · ·
Events
input event · Yes Yes Yes Yes Yes Yes Yes Yes Yes · · · · ·
change event · Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes · · ·

Some states of the type attribute define a value sanitization algorithm.

Each input element has a value, which is exposed by the value IDL attribute. Some states define an algorithm to convert a string to a number, an algorithm to convert a number to a string, an algorithm to convert a string to a Date object, and an algorithm to convert a Date object to a string, which are used by max, min, step, valueAsDate, valueAsNumber, stepDown(), and stepUp().

Each input element has a boolean dirty value flag. The dirty value flag must be initially set to false when the element is created, and must be set to true whenever the user interacts with the control in a way that changes the value. (It is also set to true when the value is programmatically changed, as described in the definition of the value IDL attribute.)

The value content attribute gives the default value of the input element. When the value content attribute is added, set, or removed, if the control's dirty value flag is false, the user agent must set the value of the element to the value of the value content attribute, if there is one, or the empty string otherwise, and then run the current value sanitization algorithm, if one is defined.

Each input element has a checkedness, which is exposed by the checked IDL attribute.

Each input element has a boolean dirty checkedness flag. When it is true, the element is said to have a dirty checkedness. The dirty checkedness flag must be initially set to false when the element is created, and must be set to true whenever the user interacts with the control in a way that changes the checkedness.

The checked content attribute is a boolean attribute that gives the default checkedness of the input element. When the checked content attribute is added, if the control does not have dirty checkedness, the user agent must set the checkedness of the element to true; when the checked content attribute is removed, if the control does not have dirty checkedness, the user agent must set the checkedness of the element to false.

The reset algorithm for input elements is to set the dirty value flag and dirty checkedness flag back to false, set the value of the element to the value of the value content attribute, if there is one, or the empty string otherwise, set the checkedness of the element to true if the element has a checked content attribute and false if it does not, empty the list of selected files, and then invoke the value sanitization algorithm, if the type attribute's current state defines one.

Each input element can be mutable. Except where otherwise specified, an input element is always mutable. Similarly, except where otherwise specified, the user agent should not allow the user to modify the element's value or checkedness.

When an input element is disabled, it is not mutable.

The readonly attribute can also in some cases (e.g. for the Date state, but not the Checkbox state) stop an input element from being mutable.

The cloning steps for input elements must propagate the value, dirty value flag, checkedness, and dirty checkedness flag from the node being cloned to the copy.

When an input element is first created, the element's rendering and behavior must be set to the rendering and behavior defined for the type attribute's state, and the value sanitization algorithm, if one is defined for the type attribute's state, must be invoked.

When an input element's type attribute changes state, the user agent must run the following steps:

  1. If the previous state of the element's type attribute put the value IDL attribute in the value mode, and the element's value is not the empty string, and the new state of the element's type attribute puts the value IDL attribute in either the default mode or the default/on mode, then set the element's value content attribute to the element's value.

  2. Otherwise, if the previous state of the element's type attribute put the value IDL attribute in any mode other than the value mode, and the new state of the element's type attribute puts the value IDL attribute in the value mode, then set the value of the element to the value of the value content attribute, if there is one, or the empty string otherwise, and then set the control's dirty value flag to false.

  3. Update the element's rendering and behavior to the new state's.

  4. Invoke the value sanitization algorithm, if one is defined for the type attribute's new state.

The name attribute represents the element's name. The dirname attribute controls how the element's directionality is submitted. The disabled attribute is used to make the control non-interactive and to prevent its value from being submitted. The form attribute is used to explicitly associate the input element with its form owner. The autofocus attribute controls focus. The inputmode attribute controls the user interface's input modality for the control. The autocomplete attribute controls how the user agent provides autofill behavior.

The indeterminate IDL attribute must initially be set to false. On getting, it must return the last value it was set to. On setting, it must be set to the new value. It has no effect except for changing the appearance of checkbox controls.

The accept, alt, max, min, multiple, pattern, placeholder, required, size, src, and step IDL attributes must reflect the respective content attributes of the same name. The dirName IDL attribute must reflect the dirname content attribute. The readOnly IDL attribute must reflect the readonly content attribute. The defaultChecked IDL attribute must reflect the checked content attribute. The defaultValue IDL attribute must reflect the value content attribute.

The type IDL attribute must reflect the respective content attribute of the same name, limited to only known values. The inputMode IDL attribute must reflect the inputmode content attribute, limited to only known values. The maxLength IDL attribute must reflect the maxlength content attribute, limited to only non-negative numbers.

The IDL attributes width and height must return the rendered width and height of the image, in CSS pixels, if an image is being rendered, and is being rendered to a visual medium; or else the intrinsic width and height of the image, in CSS pixels, if an image is available but not being rendered to a visual medium; or else 0, if no image is available. When the input element's type attribute is not in the Image Button state, then no image is available. [CSS]

On setting, they must act as if they reflected the respective content attributes of the same name.

The willValidate, validity, and validationMessage IDL attributes, and the checkValidity() and setCustomValidity() methods, are part of the constraint validation API. The labels IDL attribute provides a list of the element's labels. The select(), selectionStart, selectionEnd, selectionDirection, setRangeText(), and setSelectionRange() methods and IDL attributes expose the element's text selection. The autofocus, disabled, form, and name IDL attributes are part of the element's forms API.