Example
An HTML form with an input field that can contain only three letters (no numbers or special characters):
<form action=”/action_page.php”>
Country code: <input type=”text” name=”country_code”
pattern=”[A-Za-z]{3}” title=”Three letter country code”>
<input type=”submit”>
</form>
More “Try it Yourself” examples below.
Definition and Usage
The pattern attribute specifies a regular expression that the <input> element’s value is checked against.
Note: The pattern attribute works with the following input types: text, date, search, url, tel, email, and password.
Tip: Use the global title attribute to describe the pattern to help the user.
Tip: Learn more about regular expressions in our JavaScript tutorial.
Browser Support
The numbers in the table specify the first browser version that fully supports the attribute.
| Attribute | |||||
|---|---|---|---|---|---|
| pattern | 5.0 | 10.0 | 4.0 | 10.1 | 9.6 |
Differences Between HTML 4.01 and HTML5
The pattern attribute is new in HTML5.
Syntax
<input pattern=”regexp“>
Attribute Values
| Value | Description |
|---|---|
| regexp | Specifies a regular expression that the <input> element’s value is checked against |
