InRegexNatural Language Regex Generator
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Match Valid Username in Javascript
Explanation
This regex pattern matches a valid username that consists of alphanumeric characters (both uppercase and lowercase), underscores, with a length between 5 and 20 characters.
Javascript
Example Usage
const regex = /^[a-zA-Z0-9_]{5,20}$/;
const username = 'john_doe123';
if (regex.test(username)) {
console.log('Valid username');
} else {
console.log('Invalid username');
}Copy