Html input hidden required

HTML Input Types

This chapter describes the different types for the HTML element.

HTML Input Types

Here are the different input types you can use in HTML:

Tip: The default value of the type attribute is «text».

Input Type Text

defines a single-line text input field:

Example

This is how the HTML code above will be displayed in a browser:

Input Type Password

defines a password field:

Example

This is how the HTML code above will be displayed in a browser:

The characters in a password field are masked (shown as asterisks or circles).

Input Type Submit

defines a button for submitting form data to a form-handler.

The form-handler is typically a server page with a script for processing input data.

The form-handler is specified in the form’s action attribute:

Example

This is how the HTML code above will be displayed in a browser:

If you omit the submit button’s value attribute, the button will get a default text:

Example

Input Type Reset

defines a reset button that will reset all form values to their default values:

Example

This is how the HTML code above will be displayed in a browser:

If you change the input values and then click the «Reset» button, the form-data will be reset to the default values.

Input Type Radio

defines a radio button.

Radio buttons let a user select ONLY ONE of a limited number of choices:

Example

Choose your favorite Web language:

This is how the HTML code above will be displayed in a browser:

Input Type Checkbox

defines a checkbox.

Checkboxes let a user select ZERO or MORE options of a limited number of choices.

Example

This is how the HTML code above will be displayed in a browser:

I have a bike
I have a car
I have a boat

Input Type Button

defines a button:

Example

This is how the HTML code above will be displayed in a browser:

Input Type Color

The is used for input fields that should contain a color.

Depending on browser support, a color picker can show up in the input field.

Example

Input Type Date

The is used for input fields that should contain a date.

Depending on browser support, a date picker can show up in the input field.

Example

You can also use the min and max attributes to add restrictions to dates:

Example

Input Type Datetime-local

The specifies a date and time input field, with no time zone.

Depending on browser support, a date picker can show up in the input field.

Example

Input Type Email

The is used for input fields that should contain an e-mail address.

Depending on browser support, the e-mail address can be automatically validated when submitted.

Some smartphones recognize the email type, and add «.com» to the keyboard to match email input.

Example

Input Type Image

The defines an image as a submit button.

The path to the image is specified in the src attribute.

Example

Input Type File

The defines a file-select field and a «Browse» button for file uploads.

Example

Input Type Hidden

The defines a hidden input field (not visible to a user).

A hidden field lets web developers include data that cannot be seen or modified by users when a form is submitted.

A hidden field often stores what database record that needs to be updated when the form is submitted.

Note: While the value is not displayed to the user in the page’s content, it is visible (and can be edited) using any browser’s developer tools or «View Source» functionality. Do not use hidden inputs as a form of security!

Example

Input Type Month

The allows the user to select a month and year.

Depending on browser support, a date picker can show up in the input field.

Example

Input Type Number

The defines a numeric input field.

You can also set restrictions on what numbers are accepted.

The following example displays a numeric input field, where you can enter a value from 1 to 5:

Example

Input Restrictions

Here is a list of some common input restrictions:

Attribute	Description
checked	Specifies that an input field should be pre-selected when the page loads (for type=»checkbox» or type=»radio»)
disabled	Specifies that an input field should be disabled
max	Specifies the maximum value for an input field
maxlength	Specifies the maximum number of character for an input field
min	Specifies the minimum value for an input field
pattern	Specifies a regular expression to check the input value against
readonly	Specifies that an input field is read only (cannot be changed)
required	Specifies that an input field is required (must be filled out)
size	Specifies the width (in characters) of an input field
step	Specifies the legal number intervals for an input field
value	Specifies the default value for an input field

You will learn more about input restrictions in the next chapter.

The following example displays a numeric input field, where you can enter a value from 0 to 100, in steps of 10. The default value is 30:

Example

Input Type Range

The defines a control for entering a number whose exact value is not important (like a slider control). Default range is 0 to 100. However, you can set restrictions on what numbers are accepted with the min , max , and step attributes:

Example

Input Type Search

The is used for search fields (a search field behaves like a regular text field).

Example

Input Type Tel

The is used for input fields that should contain a telephone number.

Example

Input Type Time

The allows the user to select a time (no time zone).

Depending on browser support, a time picker can show up in the input field.

Example

Input Type Url

The is used for input fields that should contain a URL address.

Depending on browser support, the url field can be automatically validated when submitted.

Some smartphones recognize the url type, and adds «.com» to the keyboard to match url input.

Example

Input Type Week

The allows the user to select a week and year.

Depending on browser support, a date picker can show up in the input field.

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Html input hidden required

Note: The input and change events do not apply to this input type. Hidden inputs cannot be focused even using JavaScript (e.g. hiddenInput.focus() ).

Value

The element’s value attribute holds a string that contains the hidden data you want to include when the form is submitted to the server. This specifically can’t be edited or seen by the user via the user interface, although you could edit the value via browser developer tools.

Warning: While the value isn’t displayed to the user in the page’s content, it is visible—and can be edited—using any browser’s developer tools or «View Source» functionality. Do not rely on hidden inputs as a form of security.

Additional attributes

name

This is actually one of the common attributes, but it has a special meaning available for hidden inputs. Normally, the name attribute functions on hidden inputs just like on any other input. However, when the form is submitted, a hidden input whose name is set to _charset_ will automatically be reported with the value set to the character encoding used to submit the form.

Using hidden inputs

As mentioned above, hidden inputs can be used anywhere that you want to include data the user can’t see or edit along with the form when it’s submitted to the server. Let’s look at some examples that illustrate its use.

Tracking edited content

One of the most common uses for hidden inputs is to keep track of what database record needs to be updated when an edit form is submitted. A typical workflow looks like this:

1. User decides to edit some content they have control over, such as a blog post, or a product entry. They get started by pressing the edit button.
2. The content to be edited is taken from the database and loaded into an HTML form to allow the user to make changes.
3. After editing, the user submits the form, and the updated data is sent back to the server to be updated in the database.

The idea here is that during step 2, the ID of the record being updated is kept in a hidden input. When the form is submitted in step 3, the ID is automatically sent back to the server with the record content. The ID lets the site’s server-side component know exactly which record needs to be updated with the submitted data.

You can see a full example of what this might look like in the Examples section below.

Improving website security

Hidden inputs are also used to store and submit security tokens or secrets, for the purposes of improving website security. The basic idea is that if a user is filling in a sensitive form, such as a form on their banking website to transfer some money to another account, the secret they would be provided with would prove that they are who they say they are, and that they are using the correct form to submit the transfer request.

This would stop a malicious user from creating a fake form, pretending to be a bank, and emailing the form to unsuspecting users to trick them into transferring money to the wrong place. This kind of attack is called a Cross Site Request Forgery (CSRF); pretty much any reputable server-side framework uses hidden secrets to prevent such attacks.

Note: Placing the secret in a hidden input doesn’t inherently make it secure. The key’s composition and encoding would do that. The value of the hidden input is that it keeps the secret associated with the data and automatically includes it when the form is sent to the server. You need to use well-designed secrets to actually secure your website.

Validation

Hidden inputs don’t participate in constraint validation; they have no real value to be constrained.

Examples

Let’s look at how we might implement a simple version of the edit form we described earlier (see Tracking edited content), using a hidden input to remember the ID of the record being edited.

The edit form’s HTML might look a bit like this:

form> div> label for="title">Post title:label> input type="text" id="title" name="title" value="My excellent blog post" /> div> div> label for="content">Post content:label> textarea id="content" name="content" cols="60" rows="5"> This is the content of my excellent blog post. I hope you enjoy it! textarea> div> div> button type="submit">Update postbutton> div> input type="hidden" id="postId" name="postId" value="34657" /> form> 

Let’s also add some simple CSS:

html  font-family: sans-serif; > form  width: 500px; > div  display: flex; margin-bottom: 10px; > label  flex: 2; line-height: 2; text-align: right; padding-right: 20px; > input, textarea  flex: 7; font-family: sans-serif; font-size: 1.1rem; padding: 5px; > textarea  height: 60px; > 

The server would set the value of the hidden input with the ID » postID » to the ID of the post in its database before sending the form to the user’s browser and would use that information when the form is returned to know which database record to update with modified information. No scripting is needed in the content to handle this.

The output looks like this:

Note: You can also find the example on GitHub (see the source code, and also see it running live).

When submitted, the form data sent to the server will look something like this:

Even though the hidden input cannot be seen at all, its data is still submitted.

Technical summary

Specifications

Browser compatibility

BCD tables only load in the browser

See also

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This page was last modified on Mar 13, 2023 by MDN contributors.

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