URL Regex Javascript Validator

What is URL Regex in JavaScript?

In JavaScript, a URL regex (regular expression) is used to check whether a given string follows the structure of a valid web address. This can include HTTP or HTTPS links, domain names, and optional paths or query parameters. Regex helps developers filter out invalid or malformed links in user input, APIs, and forms.

URL regex patterns are useful for:

• Validating links in forms and user input

• Extracting URLs from text or logs

• Cleaning and processing data in web scraping or automation scripts

• Preventing invalid links from being submitted to servers

Common URL Regex Pattern (JavaScript)

A commonly used regex for basic URL validation is:

/^(https?:\/\/)?([\w-]+\.)+[\w-]{2,}(\/[\w\-._~:/?#[\]@!$&'()*+,;=]*)?$/

This pattern checks:

• Optional http or https

• A valid domain name

• An optional path and query string

How to Validate URLs in JavaScript Using Regex

Here’s how you can use regex to validate a URL in JavaScript:

function isValidURL(url) {
  const urlPattern = /^(https?:\/\/)?([\w-]+\.)+[\w-]{2,}(\/[\w\-._~:/?#[\]@!$&'()*+,;=]*)?$/;
  return urlPattern.test(url);
}

// Test
console.log(isValidURL("https://example.com"));           // true
console.log(isValidURL("http://my.site/path?q=1"));       // true
console.log(isValidURL("invalid-url"));                   // false

Examples of Valid and Invalid URLs

Pro Tips for Using URL Regex in JavaScript

• Use non-capturing groups when you don’t need to extract sub-matches. It improves performance.

• Combine this with the JavaScript Regex Tester to test complex patterns interactively.

• Avoid overly strict patterns—some valid URLs might be blocked unintentionally.

• Normalize input before validation (e.g., trimming whitespaces).

• Pair it with tools like the Token Generator to validate URLs containing access tokens or the Base64 Encoder for secure URL components.

Regex Metacharacters Used 

• ^ : Anchors the match at the start of the string

• $ : Anchors the match at the end of the string

• ? : Marks the preceding token as optional

• () : Capturing group

• (?:): Non-capturing group

• [] : Character set

• . : Matches any character except newline

• + : Matches one or more occurrences

• * : Matches zero or more occurrences

• \/ : Escaped slash (for path components)

Combine with These Tools

• JavaScript Regex Tester – Live test any pattern.

• Token Generator – Validate tokenized URL parameters.

• Base64 Encoder – Encode data inside URLs.

• UUID Regex JavaScript Validator – Match UUIDs used in RESTful URLs.

• Email Regex JavaScript Validator – Validate email addresses often linked in forms.

• Phone Number Regex JavaScript Validator – For contact forms that include phone and URL fields.