How to validate URLs in JavaScript (2023 edition)

There's news on the URL validation front in JavaScript land! After all these years of cursing JavaScript for not having an easy way to validate URLs, there's a new method in town — URL.canParse()!

URL.canParse('https://www.stefanjudis.com'); // true 
URL.canParse('www.stefanjudis.com'); // false

Hallelujah! URL.canParse() offers a quick way to figure out if a string is a valid URL. Can you use it today? Find up-to-date browser support information powered by MDN below. 👇

MDN Compat Data (source)

Browser support info for canParse() static method

120	120	120	115	115	17	17	25.0	120

URL.canParse() relies on the same algorithm to evaluate a valid URL as the URL() constructor.

So if the browser support above isn't working for you, could quickly polyfill canParse similar to how core-js does it or even write your own isUrlValid function.

function isUrlValid(string) {
  try {
    new URL(string);
    return true;
  } catch (err) {
    return false;
  }
}

isUrlValid('https://www.stefanjudis.com'); // true
isUrlValid('www.stefanjudis.com'); // false

Place the new URL() call in a helper function, check if it throws an exception and call it a day!

In the end, the only question remaining is "What is a valid URL?". But I'll leave this one for another time — it's a tough one.

• The GitHub issues that led to the URL.canParse() implementation