The pattern attribute in HTML is used to set a regular expression in the following input types: text, url, tel, search, date, email, and password. For passwords, with the pattern attribute, you can set the minimum required values. For example, password should have at least 8 characters.
Example
You can try to run the following code to learn how to use pattern attribute in HTML. Here, we have set the pattern for 8 or more characters in the password. If a user will add less than that, then by clicking Submit button, an error will raise i.e. “Please match the requested format: Eight or more characters”.
<!DOCTYPE html>
<html>
<body>
<h2>Register</h2>
<form action="/new.php">
Student UserName<br><input type = "text" name = "name"/><br>
Password<br><input type = "password" name = "password" pattern = ".{8,}"
title="Eight or more characters"><br><br>
<input type = "submit" value = "Submit">
</form>
</body>
</html>