562

Is there a way in JavaScript to check if a string is a URL?

RegExes are excluded because the URL is most likely written like stackoverflow; that is to say that it might not have a .com, www or http.

13
  • 37
    If it is missing the http, it is per default no url.
    – nfechner
    Apr 19, 2011 at 13:29
  • 2
    @nfechner that is to say that if it doesn't specify a protocol and use the colon character (preferably with two forward slashes next) then it is not a URL?
    – jcolebrand
    Apr 19, 2011 at 13:30
  • 7
    As you can read in the URL RFC, the only part actually neccessary to make a String a valid URL is the colon. Valid URLs look like: <scheme>:<scheme-specific-part>
    – nfechner
    Apr 19, 2011 at 13:34
  • 1
    see stackoverflow.com/a/3975573/572180
    – nguyên
    May 29, 2013 at 1:30
  • 13
    How you test whether something is a URL is highly context-dependent and too vague without further qualification. Does it matter to you whether it conforms to the URL RFC spec, works when making an OS system call to open the URL, parses as an href in an anchor element, works when calling window.open(url), points to something that really exists, works in the browser location bar, or a combination of the above? You'll get very different answers depending on which of these you care about.
    – Roy Tinker
    Apr 18, 2018 at 18:59

38 Answers 38

651

If you want to check whether a string is valid HTTP URL, you can use URL constructor (it will throw on malformed string):

function isValidHttpUrl(string) {
  let url;
  
  try {
    url = new URL(string);
  } catch (_) {
    return false;  
  }

  return url.protocol === "http:" || url.protocol === "https:";
}

Note: Per RFC 3886, URL must begin with a scheme (not limited to http/https), e. g.:

  • www.example.com is not valid URL (missing scheme)
  • javascript:void(0) is valid URL, although not an HTTP one
  • http://.. is valid URL with the host being .. (whether it resolves depends on your DNS)
  • https://example..com is valid URL, same as above
28
  • 21
    @AshD no, it's not; e.g. you can't use as href attribute for <a>. Valid URL must begin with a scheme name, e.g. https://.
    – Pavlo
    Apr 21, 2017 at 8:26
  • 9
    new URL('javascript:alert(23)')
    – blade091
    Oct 2, 2017 at 15:47
  • 11
    @Pavlo this returns true isValidUrl("javascript:void(0)")
    – Praveena
    Nov 2, 2017 at 3:55
  • 7
    I like this for teaching me new things about js! It has no false negatives that I could find. It does have some false positives: http://.. Or http:///a
    – aamarks
    Apr 16, 2018 at 16:42
  • 5
    FWIW new URL('#') return as valid
    – Sgnl
    Sep 24, 2021 at 6:12
410

A related question with an answer

Or this Regexp from Devshed:

function validURL(str) {
  var pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol
    '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name
    '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
    '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
    '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
    '(\\#[-a-z\\d_]*)?$','i'); // fragment locator
  return !!pattern.test(str);
}
28
166
function isURL(str) {
  var pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol
  '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.?)+[a-z]{2,}|'+ // domain name
  '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
  '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
  '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
  '(\\#[-a-z\\d_]*)?$','i'); // fragment locator
  return pattern.test(str);
}
16
  • 17
    fails for google search image links : http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707
    – bill davis
    Apr 23, 2014 at 0:23
  • 9
    this is unusable slow Jan 28, 2015 at 3:00
  • 10
    @HernánEche What so you mean by slow? start = new Date(); isURL("http://michalstefanow.com"); end = new Date(); diff = end - start; console.log(diff) I put a kettle on, went to a toilet, called my mum and the thing was done in no time... May 2, 2016 at 13:59
  • 78
    It returns true for aaa. Dec 1, 2016 at 9:13
  • 4
    This absolutely should not be the correct answer. It fails many test cases and more importantly it hangs your page on even a short string: isURL('12345678901234567890123') add some more characters and it's even worse.
    – aamarks
    Apr 16, 2018 at 16:51
117

Rather than using a regular expression, I would recommend making use of an anchor element.

when you set the href property of an anchor, various other properties are set.

var parser = document.createElement('a');
parser.href = "http://example.com:3000/pathname/?search=test#hash";

parser.protocol; // => "http:"
parser.hostname; // => "example.com"
parser.port;     // => "3000"
parser.pathname; // => "/pathname/"
parser.search;   // => "?search=test"
parser.hash;     // => "#hash"
parser.host;     // => "example.com:3000"

source

However, if the value href is bound to is not a valid url, then the value of those auxiliary properties will be the empty string.

Edit: as pointed out in the comments: if an invalid url is used, the properties of the current URL may be substituted.

So, as long as you're not passing in the URL of the current page, you can do something like:

function isValidURL(str) {
   var a  = document.createElement('a');
   a.href = str;
   return (a.host && a.host != window.location.host);
}
12
  • 8
    This isn't the case (in Chrome 48 at least). If the url passed to a.href is invalid, parser.host returns the hostname of the page you're currently on, not the expected false. Feb 25, 2016 at 15:37
  • 3
    Gah! that's weird. I swear I tested this! I think it's fair to say that this wont really ever have to be used ON the current page, so the conditional can just be changed. I'll edit the post.
    – Luke
    Feb 25, 2016 at 22:48
  • it is not a very typical use case, but this technique does not work in the context of Firefox browser window (important for addon development)
    – chrmod
    May 15, 2016 at 16:01
  • 6
    function isValidURL(str): so much better than using regex! Thank you!
    – Rodrigo
    Apr 13, 2018 at 15:55
  • 1
    Pretty simple way to hack around the problem. These properties are experimental though: developer.mozilla.org/en-US/docs/Web/API/HTMLAnchorElement Nov 30, 2018 at 14:19
106
+50

I am using below function to validate URL with or without http/https:

function isValidURL(string) {
  var res = string.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g);
  return (res !== null)
};

var testCase1 = "http://en.wikipedia.org/wiki/Procter_&_Gamble";
console.log(isValidURL(testCase1)); // return true

var testCase2 = "http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707";
console.log(isValidURL(testCase2)); // return true

var testCase3 = "https://sdfasd";
console.log(isValidURL(testCase3)); // return false

var testCase4 = "dfdsfdsfdfdsfsdfs";
console.log(isValidURL(testCase4)); // return false

var testCase5 = "magnet:?xt=urn:btih:123";
console.log(isValidURL(testCase5)); // return false

var testCase6 = "https://stackoverflow.com/";
console.log(isValidURL(testCase6)); // return true

var testCase7 = "https://w";
console.log(isValidURL(testCase7)); // return false

var testCase8 = "https://sdfasdp.ppppppppppp";
console.log(isValidURL(testCase8)); // return false

15
  • 2
    Seems a nice solution! Could you add some tests showing it works in some corner cases (see for example these comments)?
    – Basj
    Apr 16, 2018 at 7:36
  • @Basj added test cases. Please check Apr 16, 2018 at 8:00
  • 6
    its returning true for [email protected]...should it? I guess it should not
    – Zohab Ali
    Jan 2, 2019 at 9:05
  • 3
    This fails when the URL has a port.
    – Wedava
    Jul 22, 2019 at 9:15
  • 1
    this code is not validating protocol See your self url = 'htt1ps://googl1e.com' console.log(url + ' -> ' + isValidURL(url)) Jun 16, 2020 at 14:22
52

To Validate Url using javascript is shown below

function ValidURL(str) {
  var regex = /(?:https?):\/\/(\w+:?\w*)?(\S+)(:\d+)?(\/|\/([\w#!:.?+=&%!\-\/]))?/;
  if(!regex .test(str)) {
    alert("Please enter valid URL.");
    return false;
  } else {
    return true;
  }
}
2
  • "mailto:[email protected]" this is a link but ur code is not work. How can I fix?
    – Tu Le Anh
    Apr 20, 2022 at 16:52
  • URLs that use http or https are only for web addresses. There are a multitude of others that do not use those schemes and they are valid also.
    – Suncat2000
    May 4, 2022 at 21:25
31

Rely on a library: https://www.npmjs.com/package/valid-url

import { isWebUri } from 'valid-url';
// ...
if (!isWebUri(url)) {
    return "Not a valid url.";
}
1
  • 2
    this one gives me a lot of trouble with weird urls that are actually parsed by the browser, e.g.: having a { in the url
    – Willyfrog
    Jun 19, 2020 at 8:56
27

Improvement on the accepted answer...

  • Check for ftp/ftps as protocol
  • Has double escaping for backslashes (\\)
  • Ensures that domains have a dot and an extension (.com .io .xyz)
  • Allows full colon (:) in the path e.g. http://thingiverse.com/download:1894343
  • Allows ampersand (&) in path e.g http://en.wikipedia.org/wiki/Procter_&_Gamble
  • Allows @ symbol in path e.g. https://medium.com/@techytimo

    isURL(str) {
      var pattern = new RegExp('^((ft|htt)ps?:\\/\\/)?'+ // protocol
      '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name and extension
      '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
      '(\\:\\d+)?'+ // port
      '(\\/[-a-z\\d%@_.~+&:]*)*'+ // path
      '(\\?[;&a-z\\d%@_.,~+&:=-]*)?'+ // query string
      '(\\#[-a-z\\d_]*)?$','i'); // fragment locator
      return pattern.test(str);
    }
    
8
  • 6
    No it shouldn't be the accepted answer. Like some of the others it hangs on a mere 33 character string: isURL('123456789012345678901234567890123') and fails many edge case tests: foo.com/blah_blah_(wikipedia)_(again) //incorrectly returns false.
    – aamarks
    Apr 16, 2018 at 16:23
  • 2
    That is because localhost:8080 isn't a valid URL.
    – Shanerk
    Oct 12, 2018 at 18:56
  • 1
    Working sample: runkit.com/shanekenyon87/5bc0e57263c77b0012db05dc
    – Shanerk
    Oct 12, 2018 at 19:07
  • Should be ftps://localhost:8080 =)
    – vp_arth
    Feb 10, 2019 at 21:22
  • 1
    It doesn't seem to work: hangs on long input (like @aanmarks said)
    – cecemel
    Mar 28, 2019 at 16:50
24

You can use the URL native API:

  const isUrl = string => {
      try { return Boolean(new URL(string)); }
      catch(e){ return false; }
  }
2
  • 4
    Looks very similar to the answer provided by @pavlo, only variable names changed ;) Apr 16, 2018 at 21:28
  • 2
    there should really be a simple native method to check for this by now - this answer looked very promising but it returns true early as @Basj mentioned above.
    – zero_cool
    Sep 6, 2018 at 6:11
20

Use validator.js

ES6

import isURL from 'validator/lib/isURL'

isURL(string)

No ES6

var validator = require('validator');

validator.isURL(string)

You can also fine tune this function's behavior by passing optional options object as the second argument of isURL

Here is the default options object:

let options = {
    protocols: [
        'http',
        'https',
        'ftp'
    ],
    require_tld: true,
    require_protocol: false,
    require_host: true,
    require_valid_protocol: true,
    allow_underscores: false,
    host_whitelist: false,
    host_blacklist: false,
    allow_trailing_dot: false,
    allow_protocol_relative_urls: false,
    disallow_auth: false
}

isURL(string, options)

host_whitelist and host_blacklist can be arrays of hosts. They also support regular expressions.

let options = {
    host_blacklist: ['foo.com', 'bar.com'],
}

isURL('http://foobar.com', options) // => true
isURL('http://foo.bar.com/', options) // => true
isURL('http://qux.com', options) // => true

isURL('http://bar.com/', options) // => false
isURL('http://foo.com/', options) // => false


options = {
    host_blacklist: ['bar.com', 'foo.com', /\.foo\.com$/],
}

isURL('http://foobar.com', options) // => true
isURL('http://foo.bar.com/', options) // => true
isURL('http://qux.com', options) // => true

isURL('http://bar.com/', options) // => false
isURL('http://foo.com/', options) // => false
isURL('http://images.foo.com/', options) // => false
isURL('http://cdn.foo.com/', options) // => false
isURL('http://a.b.c.foo.com/', options) // => false
5
  • 5
    Nice! Small library (less than 40k minified), popular library (over 3M weekly downloads on npm), gives you tons of flexibility on specifying the validity of the URLs for your particular use case, and has a number of other validators besides URL. This is by far the best answer, IMHO. Mar 26, 2020 at 2:07
  • 1
    Nice library. It can validate URL but also many other things.
    – Bemipefe
    Dec 2, 2020 at 11:09
  • 1
    This worked for me when creating a New Relic Synthetics script. Very useful. May 19, 2021 at 23:19
  • 1
    The best solution by far Jul 25, 2021 at 22:15
  • I am sorry, @JavidJamae? Is 40K a small library when "minified"? There's a 3D video game .kkrieger the size of which is less than 100K ^^
    – Artfaith
    Jul 10, 2023 at 17:51
16

Here is yet another method.

// ***note***: if the incoming value is empty(""), the function returns true

var elm;
function isValidURL(u){
  //A precaution/solution for the problem written in the ***note***
  if(u!==""){  
      if(!elm){
      elm = document.createElement('input');
      elm.setAttribute('type', 'url');
      }
  elm.value = u;
  return elm.validity.valid;
  }
  else{
      return false
  }
}

console.log(isValidURL(''));
console.log(isValidURL('http://www.google.com/'));
console.log(isValidURL('//google.com'));
console.log(isValidURL('google.com'));
console.log(isValidURL('localhost:8000'));

3
  • Educational code! The mechanism here is probably identical to how new URL(string) in Pavlo's code works. Both tests have identical results with all the edge cases I tested. I like his code because it is simpler and doesn't involve creating elements, but yours is a few times faster (probably because it doesn't create the el after the first use).
    – aamarks
    Apr 23, 2018 at 22:05
  • 1
    Thank you! I implemented your advice. Be aware however: Older browsers and/or mobile device WebView may have not implemented the <input type =url> element; thus the input value would be treated just like a regular text (no URL validation). REF: developer.mozilla.org/en-US/docs/Web/HTML/Element/input/url Dec 7, 2018 at 15:17
  • To avoid empty values from returning true using the Constrain validation API, you also have to set required to true on the input field. Apr 16, 2022 at 13:00
15

As has been noted the perfect regex is elusive but still seems to be a reasonable approach (alternatives are server side tests or the new experimental URL API). However the high ranking answers are often returning false for common URLs but even worse will freeze your app/page for minutes on even as simple a string as isURL('aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa'). It's been pointed out in some of the comments, but most probably haven't entered a bad value to see it. Hanging like that makes that code unusable in any serious application. I think it's due to the repeated case insensitive sets in code like ((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.?)+[a-z]{2,}|' .... Take out the 'i' and it doesn't hang but will of course not work as desired. But even with the ignore case flag those tests reject high unicode values that are allowed.

The best already mentioned is:

function isURL(str) {
  return /^(?:\w+:)?\/\/([^\s\.]+\.\S{2}|localhost[\:?\d]*)\S*$/.test(str); 
}

That comes from Github segmentio/is-url. The good thing about a code repository is you can see the testing and any issues and also the test strings run through it. There's a branch that would allow strings missing protocol like google.com, though you're probably making too many assumptions then. The repository has been updated and I'm not planning on trying to keep up a mirror here. It's been broken up into separate tests to avoid RegEx redos which can be exploited for DOS attacks (I don't think you have to worry about that with client side js, but you do have to worry about your page hanging for so long that your visitor leaves your site).

There is one other repository I've seen that may even be better for isURL at dperini/regex-weburl.js, but it is highly complex. It has a bigger test list of valid and invalid URLs. The simple one above still passes all the positives and only fails to block a few odd negatives like http://a.b--c.de/ as well as the special ips.

Whichever you choose, run it through this function which I've adapted from the tests on dperini/regex-weburl.js, while using your browser's Developer Tools inpector.

function testIsURL() {
//should match
console.assert(isURL("http://foo.com/blah_blah"));
console.assert(isURL("http://foo.com/blah_blah/"));
console.assert(isURL("http://foo.com/blah_blah_(wikipedia)"));
console.assert(isURL("http://foo.com/blah_blah_(wikipedia)_(again)"));
console.assert(isURL("http://www.example.com/wpstyle/?p=364"));
console.assert(isURL("https://www.example.com/foo/?bar=baz&inga=42&quux"));
console.assert(isURL("http://✪df.ws/123"));
console.assert(isURL("http://userid:[email protected]:8080"));
console.assert(isURL("http://userid:[email protected]:8080/"));
console.assert(isURL("http://[email protected]"));
console.assert(isURL("http://[email protected]/"));
console.assert(isURL("http://[email protected]:8080"));
console.assert(isURL("http://[email protected]:8080/"));
console.assert(isURL("http://userid:[email protected]"));
console.assert(isURL("http://userid:[email protected]/"));
console.assert(isURL("http://142.42.1.1/"));
console.assert(isURL("http://142.42.1.1:8080/"));
console.assert(isURL("http://➡.ws/䨹"));
console.assert(isURL("http://⌘.ws"));
console.assert(isURL("http://⌘.ws/"));
console.assert(isURL("http://foo.com/blah_(wikipedia)#cite-1"));
console.assert(isURL("http://foo.com/blah_(wikipedia)_blah#cite-1"));
console.assert(isURL("http://foo.com/unicode_(✪)_in_parens"));
console.assert(isURL("http://foo.com/(something)?after=parens"));
console.assert(isURL("http://☺.damowmow.com/"));
console.assert(isURL("http://code.google.com/events/#&product=browser"));
console.assert(isURL("http://j.mp"));
console.assert(isURL("ftp://foo.bar/baz"));
console.assert(isURL("http://foo.bar/?q=Test%20URL-encoded%20stuff"));
console.assert(isURL("http://مثال.إختبار"));
console.assert(isURL("http://例子.测试"));
console.assert(isURL("http://उदाहरण.परीक्षा"));
console.assert(isURL("http://-.~_!$&'()*+,;=:%40:80%2f::::::@example.com"));
console.assert(isURL("http://1337.net"));
console.assert(isURL("http://a.b-c.de"));
console.assert(isURL("http://223.255.255.254"));
console.assert(isURL("postgres://u:[email protected]:5702/db"));
console.assert(isURL("https://[email protected]/13176"));

//SHOULD NOT MATCH:
console.assert(!isURL("http://"));
console.assert(!isURL("http://."));
console.assert(!isURL("http://.."));
console.assert(!isURL("http://../"));
console.assert(!isURL("http://?"));
console.assert(!isURL("http://??"));
console.assert(!isURL("http://??/"));
console.assert(!isURL("http://#"));
console.assert(!isURL("http://##"));
console.assert(!isURL("http://##/"));
console.assert(!isURL("http://foo.bar?q=Spaces should be encoded"));
console.assert(!isURL("//"));
console.assert(!isURL("//a"));
console.assert(!isURL("///a"));
console.assert(!isURL("///"));
console.assert(!isURL("http:///a"));
console.assert(!isURL("foo.com"));
console.assert(!isURL("rdar://1234"));
console.assert(!isURL("h://test"));
console.assert(!isURL("http:// shouldfail.com"));
console.assert(!isURL(":// should fail"));
console.assert(!isURL("http://foo.bar/foo(bar)baz quux"));
console.assert(!isURL("ftps://foo.bar/"));
console.assert(!isURL("http://-error-.invalid/"));
console.assert(!isURL("http://a.b--c.de/"));
console.assert(!isURL("http://-a.b.co"));
console.assert(!isURL("http://a.b-.co"));
console.assert(!isURL("http://0.0.0.0"));
console.assert(!isURL("http://10.1.1.0"));
console.assert(!isURL("http://10.1.1.255"));
console.assert(!isURL("http://224.1.1.1"));
console.assert(!isURL("http://1.1.1.1.1"));
console.assert(!isURL("http://123.123.123"));
console.assert(!isURL("http://3628126748"));
console.assert(!isURL("http://.www.foo.bar/"));
console.assert(!isURL("http://www.foo.bar./"));
console.assert(!isURL("http://.www.foo.bar./"));
console.assert(!isURL("http://10.1.1.1"));}

And then test that string of 'a's.

See this comparison of isURL regex by Mathias Bynens for more info before you post a seemingly great regex.

3
  • 1
    I checked your answer. Your answer is failing for sdfasdp.ppppppppppp i.e. returning true but expected is false Apr 17, 2018 at 8:26
  • 2
    I think that's a valid URL, structurally. Not an expert on the standard but I don't think there's a limit on the length of the .com portion (I know .online is legit).
    – aamarks
    Apr 17, 2018 at 22:12
  • 1
    I barely knew how to write a regex a couple of months ago. The problem is severe. Both of the regex I quoted can complete isURL('a'.repeat(100)) millions of times/sec (the more complex one from dperini is actually faster). Some of the high ranking answers of the form ([a-zA-Z]+)* would take hours to complete that once. Look up RegEx redos for more information.
    – aamarks
    Apr 23, 2018 at 20:27
15

This function disallows localhost and only allows URLs for web pages (ie, only allows http or https protocol).

It also only allows safe characters as defined here: https://www.urlencoder.io/learn/

function isValidWebUrl(url) {
   let regEx = /^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)$/gm;
   return regEx.test(url);
}
1
  • This best met my use case. Does the /g make any sense, though, since you can't match more than one and wouldn't want to?
    – Geoduck
    Apr 19, 2021 at 19:09
12

(I don't have reps to comment on ValidURL example; hence post this as an answer.)

While use of protocol relative URLs is not encouraged (The Protocol-relative URL), they do get employed sometimes. To validate such an URL with a regular expression the protocol part could be optional, e.g.:

function isValidURL(str) {
    var pattern = new RegExp('^((https?:)?\\/\\/)?'+ // protocol
        '(?:\\S+(?::\\S*)?@)?' + // authentication
        '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name
        '((\\d{1,3}\\.){3}\\d{1,3}))'+ // OR ip (v4) address
        '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
        '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
        '(\\#[-a-z\\d_]*)?$','i'); // fragment locater
    if (!pattern.test(str)) {
        return false;
    } else {
        return true;
    }
}

As others noted, regular expression does not seem to be the best suited approach for validating URLs, though.

3
  • I thought at first this was pretty good but it fails many of the tests at mathiasbynens.be/demo/url-regex, and then it hangs on isValidURL("https://[email protected]/13176")
    – aamarks
    Apr 23, 2018 at 21:21
  • Yes, like I said, I merely commented on the protocol part. I added the authentication clause to handle @. It doesn't hang in my browsers.
    – ko la
    Apr 25, 2018 at 3:23
  • Sorry, I was going through several of these to evaluate them and missed that yours was commenting on the given answer. I think your correction even helped me get started on these when I first visited this page. Not hanging now.
    – aamarks
    Apr 25, 2018 at 4:42
9

One function that I have been using to validate a URL "string" is:

var matcher = /^(?:\w+:)?\/\/([^\s\.]+\.\S{2}|localhost[\:?\d]*)\S*$/;

function isUrl(string){
  return matcher.test(string);
}

This function will return a boolean whether the string is a URL.

Examples:

isUrl("https://google.com");     // true
isUrl("http://google.com");      // true
isUrl("http://google.de");       // true
isUrl("//google.de");            // true
isUrl("google.de");              // false
isUrl("http://google.com");      // true
isUrl("http://localhost");       // true
isUrl("https://sdfasd");         // false
9

This is quite difficult to do with pure regex because URLs have many 'inconveniences'.

  1. For example domain names have complicated restrictions on hyphens:

    a. It is allowed to have many consecutive hyphens in the middle.

    b. but the first character and last character of the domain name cannot be a hyphen

    c. The 3rd and 4th character cannot be both hyphen

  2. Similarly port number can only be in the range 1-65535. This is easy to check if you extract the port part and convert to int but quite difficult to check with a regular expression.

  3. There is also no easy way to check valid domain extensions. Some countries have second-level domains(such as 'co.uk'), or the extension can be a long word such as '.international'. And new TLDs are added regularly. This type of things can only be checked against a hard-coded list. (see https://en.wikipedia.org/wiki/Top-level_domain)

  4. Then there are magnet urls, ftp addresses etc. These all have different requirements.

Nevertheless, here is a function that handles pretty much everything except:

  • Case 1. c
  • Accepts any 1-5 digit port number
  • Accepts any extension 2-13 chars
  • Does not accept ftp, magnet, etc...

function isValidURL(input) {
    pattern = '^(https?:\\/\\/)?' + // protocol
        '((([a-zA-Z\\d]([a-zA-Z\\d-]{0,61}[a-zA-Z\\d])*\\.)+' + // sub-domain + domain name
        '[a-zA-Z]{2,13})' + // extension
        '|((\\d{1,3}\\.){3}\\d{1,3})' + // OR ip (v4) address
        '|localhost)' + // OR localhost
        '(\\:\\d{1,5})?' + // port
        '(\\/[a-zA-Z\\&\\d%_.~+-:@]*)*' + // path
        '(\\?[a-zA-Z\\&\\d%_.,~+-:@=;&]*)?' + // query string
        '(\\#[-a-zA-Z&\\d_]*)?$'; // fragment locator
    regex = new RegExp(pattern);
    return regex.test(input);
}

let tests = [];
tests.push(['', false]);
tests.push(['http://en.wikipedia.org/wiki/Procter_&_Gamble', true]);
tests.push(['https://sdfasd', false]);
tests.push(['http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707', true]);
tests.push(['https://stackoverflow.com/', true]);
tests.push(['https://w', false]);
tests.push(['aaa', false]);
tests.push(['aaaa', false]);
tests.push(['oh.my', true]);
tests.push(['dfdsfdsfdfdsfsdfs', false]);
tests.push(['google.co.uk', true]);
tests.push(['test-domain.MUSEUM', true]);
tests.push(['-hyphen-start.gov.tr', false]);
tests.push(['hyphen-end-.com', false]);
tests.push(['https://sdfasdp.international', true]);
tests.push(['https://sdfasdp.pppppppp', false]);
tests.push(['https://sdfasdp.ppppppppppppppppppp', false]);
tests.push(['https://sdfasd', false]);
tests.push(['https://sub1.1234.sub3.sub4.sub5.co.uk/?', true]);
tests.push(['http://www.google-com.123', false]);
tests.push(['http://my--testdomain.com', false]);
tests.push(['http://my2nd--testdomain.com', true]);
tests.push(['http://thingiverse.com/download:1894343', true]);
tests.push(['https://medium.com/@techytimo', true]);
tests.push(['http://localhost', true]);
tests.push(['localhost', true]);
tests.push(['localhost:8080', true]);
tests.push(['localhost:65536', true]);
tests.push(['localhost:80000', false]);
tests.push(['magnet:?xt=urn:btih:123', true]);

for (let i = 0; i < tests.length; i++) {
    console.log('Test #' + i + (isValidURL(tests[i][0]) == tests[i][1] ? ' passed' : ' failed') + ' on ["' + tests[i][0] + '", ' + tests[i][1] + ']');
}

1
8

There's a lot of answers already, but here's another contribution: Taken directly from the URL polyfill validity check, use an input element with type="url" to take advantage of the browser's built-in validity check:

var inputElement = doc.createElement('input');
inputElement.type = 'url';
inputElement.value = url;

if (!inputElement.checkValidity()) {
    throw new TypeError('Invalid URL');
}

Source

4

Mathias Bynens has compiled a list of well-known URL regexes with test URLs. There is little reason to write a new regular expression; just pick an existing one that suits you best.

But the comparison table for those regexes also shows that it is next to impossible to do URL validation with a single regular expression. All of the regexes in Bynens' list produce false positives and false negatives.

I suggest that you use an existing URL parser (for example new URL('http://www.example.com/') in JavaScript) and then apply the checks you want to perform against the parsed and normalized form of the URL resp. its components. Using the JavaScript URL interface has the additional benefit that it will only accept such URLs that are really accepted by the browser.

You should also keep in mind that technically incorrect URLs may still work. For example http://w_w_w.example.com/, http://www..example.com/, http://123.example.com/ all have an invalid hostname part but every browser I know will try to open them without complaints, and when you specify IP addresses for those invalid names in /etc/hosts/ such URLs will even work but only on your computer.

The question is, therefore, not so much whether a URL is valid, but rather which URLs work and should be allowed in a particular context.

If you want to do URL validation there are a lot of details and edge cases that are easy to overlook:

  • URLs may contain credentials as in http://user:[email protected]/.
  • Port numbers must be in the range of 0-65535, but you may still want to exclude the wildcard port 0.
  • Port numbers may have leading zeros as in http://www.example.com:000080/.
  • IPv4 addresses are by no means restricted to 4 decimal integers in the range of 0-255. You can use one to four integers, and they can be decimal, octal or hexadecimal. The URLs https://010.010.000010.010/, https://0x8.0x8.0x0008.0x8/, https://8.8.2056/, https://8.526344/, https://134744072/ are all valid and just creative ways of writing https://8.8.8.8/.
  • Allowing loopback addresses (http://127.0.0.1/), private IP addresses (http://192.168.1.1), link-local addresses (http://169.254.100.200) and so on may have an impact on security or privacy. If, for instance, you allow them as the address of user avatars in a forum, you cause the users' browsers to send unsolicited network requests in their local network and in the internet of things such requests may cause funny and not so funny things to happen in your home.
  • For the same reasons, you may want to discard links to not fully qualified hostnames, in other words hostnames without a dot.
  • But hostnames may always have a trailing dot (like in http://www.stackoverflow.com.).
  • The hostname portion of a link may contain angle brackets for IPv6 addresses as in http://[::1].
  • IPv6 addresses also have ranges for private networks or link-local addresses etc.
  • If you block certain IPv4 addresses, keep in mind that for example https://127.0.0.1 and https://[::ffff:127.0.0.1] point to the same resource (if the loopback device of your machine is IPv6 ready).
  • The hostname portion of URLs may now contain Unicode, so that the character range [-0-9a-zA-z] is definitely no longer sufficient.
  • Many registries for top-level domains define specific restrictions, for example on the allowed set of Unicode characters. Or they subdivide their namespace (like co.uk and many others).
  • Top-level domains must not contain decimal digits, and the hyphen is not allowed unless for the IDN A-label prefix "xn--".
  • Unicode top-level domains (and their punycode encoding with "xn--") must still contain only letters but who wants to check that in a regex?

Which of these limitations and rules apply is a question of project requirements and taste.

I have recently written a URL validator for a web app that is suitable for user-supplied URLs in forums, social networks, or the like. Feel free to use it as a base for your own one:

I have also written a blog post The Gory Details of URL Validation with more in-depth information.

3

this working with me

function isURL(str) {
  var regex = /(http|https):\/\/(\w+:{0,1}\w*)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%!\-\/]))?/;
  var pattern = new RegExp(regex); 
return pattern.test(str);
}
2
  • 1
    This answer was already given above 4 years ago by kavitha Reddy.
    – aamarks
    Jun 1, 2019 at 19:09
  • i just made it more simple and abstract Feb 20, 2020 at 13:15
3

There are a couple of tests using the URL constructor which do not delineate whether the input is a string or URL object.

// Testing whether something is a URL
function isURL(url) {
    return toString.call(url) === "[object URL]";
}

// Testing whether the input is both a string and valid url:
function isUrl(url) {
    try {
        return toString.call(url) === "[object String]" && !!(new URL(url));
    } catch (_) {
        return false;  
    }
}
3

I had revised all the comments, notes and remarks is this topic and have made a new regular expression:

^((javascript:[\w-_]+(\([\w-_\s,.]*\))?)|(mailto:([\w\u00C0-\u1FFF\u2C00-\uD7FF-_]+\.)*[\w\u00C0-\u1FFF\u2C00-\uD7FF-_]+@([\w\u00C0-\u1FFF\u2C00-\uD7FF-_]+\.)*[\w\u00C0-\u1FFF\u2C00-\uD7FF-_]+)|(\w+:\/\/(([\w\u00C0-\u1FFF\u2C00-\uD7FF-]+\.)*([\w\u00C0-\u1FFF\u2C00-\uD7FF-]*\.?))(:\d+)?(((\/[^\s#$%^&*?]+)+|\/)(\?[\w\u00C0-\u1FFF\u2C00-\uD7FF:;&%_,.~+=-]+)?)?(#[\w\u00C0-\u1FFF\u2C00-\uD7FF-_]+)?))$

You can test and improve it here https://regexr.com/668mt .

I checked this expression on next values:

http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707
http://192.168.0.4:55/
https://web.archive.org/web/20170817095211/https://github.com/Microsoft/vscode/issues/32405
http://www.example.com
javascript:void()
http://.
https://example.
https://en.m.wikipedia.org/wiki/C_Sharp_(programming_language)
http://zh.wikipedia.org/wiki/Wikipedia:关于中文维基百科/en?a#a
https://medium.com/@User_name/
https://test-test-test-test-test-test-test-test-test.web.app/
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707
https://sdfasdp.ppppppppppp
mailto:[email protected]
https://тест.юа
2

If you need to also support https://localhost:3000 then use this modified version of [Devshed]s regex.

    function isURL(url) {
        if(!url) return false;
        var pattern = new RegExp('^(https?:\\/\\/)?'+ // protocol
            '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|'+ // domain name
            '((\\d{1,3}\\.){3}\\d{1,3}))|' + // OR ip (v4) address
            'localhost' + // OR localhost
            '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*'+ // port and path
            '(\\?[;&a-z\\d%_.~+=-]*)?'+ // query string
            '(\\#[-a-z\\d_]*)?$', 'i'); // fragment locator
        return pattern.test(url);
    }
2

I change the function to Match + make a change here with the slashes and its work: (http:// and https) both

function isValidUrl(userInput) {
    var res = userInput.match(/(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g);
    if(res == null)
       return false;
    else
       return true;
}
1
  • In 2021, this worked for me in all URL configurations Jan 21, 2021 at 17:16
2

Since Node v19.9.0 you can use URL.canParse(input, [base]).

  • input: <string> The absolute or relative input URL to parse. If input is relative, then base is required. If input is absolute, the base is ignored. If input is not a string, it is converted to a string first.
  • base: <string> The base URL to resolve against if the input is not absolute. If base is not a string, it is converted to a string first.

https://nodejs.org/api/url.html#urlcanparseinput-base

URL.canParse('https://example.org/foo'); // TRUE
URL.canParse('nothttps://example.org/foo'); // FALSE

Browser support is (very) limited at the moment. See https://developer.mozilla.org/en-US/docs/Web/API/URL/canParse_static

1

I think using the native URL API is better than a complex regex patterns as @pavlo suggested. It has some drawbacks though which we can fix by some extra code. This approach fails for the following valid url.

//cdn.google.com/script.js

We can add the missing protocol beforehand to avoid that. It also fails to detect following invalid url.

http://w
http://..

So why check the whole url? we can just check the domain. I borrowed the regex to verify domain from here.

function isValidUrl(string) {
    if (string && string.length > 1 && string.slice(0, 2) == '//') {
        string = 'http:' + string; //dummy protocol so that URL works
    }
    try {
        var url = new URL(string);
        return url.hostname && url.hostname.match(/^([a-z0-9])(([a-z0-9-]{1,61})?[a-z0-9]{1})?(\.[a-z0-9](([a-z0-9-]{1,61})?[a-z0-9]{1})?)?(\.[a-zA-Z]{2,4})+$/) ? true : false;
    } catch (_) {
        return false;
    }
}

The hostname attribute is empty string for javascript:void(0), so it works for that too, and you can also add IP address verifier too. I'd like to stick to native API's most, and hope it starts to support everything in near future.

1
  • Interesting, but may still need to work on the regex as it's now introduced false negatives which new URL doesn't have in the tests I've done. This is calling: http://142.42.1.1 //false and blocking high unicode strings.
    – aamarks
    Apr 23, 2018 at 22:17
1

The question asks a validation method for an url such as stackoverflow, without the protocol or any dot in the hostname. So, it's not a matter of validating url sintax, but checking if it's a valid url, by actually calling it.

I tried several methods for knowing if the url true exists and is callable from within the browser, but did not find any way to test with javascript the response header of the call:

  • adding an anchor element is fine for firing the click() method.
  • making ajax call to the challenging url with 'GET' is fine, but has it's various limitations due to CORS policies and it is not the case of using ajax, for as the url maybe any outside my server's domain.
  • using the fetch API has a workaround similar to ajax.
  • other problem is that I have my server under https protocol and throws an exception when calling non secure urls.

So, the best solution I can think of is getting some tool to perform CURL using javascript trying something like curl -I <url>. Unfortunately I did not find any and in appereance it's not possible. I will appreciate any comments on this.

But, in the end, I have a server running PHP and as I use Ajax for almost all my requests, I wrote a function on the server side to perform the curl request there and return to the browser.

Regarding the single word url on the question 'stackoverflow' it will lead me to https://daniserver.com.ar/stackoverflow, where daniserver.com.ar is my own domain.

1
  • The OP should probably have indicated more of what his intent was. The problem certainly varies upon your needs and whether it's more important to exclude false positives or include false negatives. As the problem is stated there seems to be no answer to me. Can you really take foo and assume it's http or https or .com or .es or any of the countless suffixes? Do you keep throwing the kitchen sink at it until you get a true?
    – aamarks
    Apr 23, 2018 at 21:45
1

This seems to be one of the hardest problems in CS ;)

Here's another incomplete solution that works well enough for me and better than the others I've seen here. I'm using a input[type=url] for this in order to support IE11, otherwise it would be much simpler using window.URL to perform the validation instead:

const ipv4Regex = /^(\d{1,3}\.){3}\d{1,3}$/;
function isValidIpv4(ip) {
  if (!ipv4Regex.test(ip)) return false;
  return !ip.split('.').find(n => n > 255);
}

const domainRegex = /(?:[a-z0-9-]{1,63}\.){1,125}[a-z]{2,63}$/i;
function isValidDomain(domain) {
  return isValidIpv4(domain) || domainRegex.test(domain);
}

let input;
function validateUrl(url) {
  if (! /^https?:\/\//.test(url)) url = `http://${url}`; // assuming Babel is used
  // to support IE11 we'll resort to input[type=url] instead of window.URL:
  // try { return isValidDomain(new URL(url).host) && url; } catch(e) { return false; }
  if (!input) { input = document.createElement('input'); input.type = 'url'; }
  input.value = url;
  if (! input.validity.valid) return false;
  const domain = url.split(/^https?:\/\//)[1].split('/')[0].split('@').pop();
  return isValidDomain(domain) && url;
}

console.log(validateUrl('google'), // false
  validateUrl('user:[email protected]'),
  validateUrl('https://google.com'),
  validateUrl('100.100.100.100/abc'),
  validateUrl('100.100.100.256/abc')); // false

In order to accept incomplete inputs such as "www.mydomain.com" it will also make it valid assuming the protocol is "http" in those cases and returning the valid URL if the address is valid. It returns false when invalid.

It also supports IPv4 domains, but not IPv6.

1

In my case my only requirement is that the user input won't be interpreted as a relative link when placed in the href of an a tag and the answers here were either a bit OTT for that or allowed URLs not meeting my requirements, so this is what I'm going with:

^https?://.+$

The same thing could be achieved pretty easily without regex.

1

If you can change the input type, I think this solution would be much easier:

You can simple use type="url" in your input and the check it with checkValidity() in js

E.g:

your.html

<input id="foo" type="url">

your.js

// The selector is JQuery, but the function is plain JS
$("#foo").on("keyup", function() {
    if (this.checkValidity()) {
        // The url is valid
    } else {
        // The url is invalid
    }
});
1

Using URL Class

/**
  * The given value must start with a protocol (e.g., http:// or https://)
  * If the value doesn't start with a protocol,
  * the function may return false.
*/
function testWithUrlClass(urlStr) {
    try {
    new URL(urlStr);
    return true;
  } catch(e) {
    return false;
  }
}

difficult to do with pure regex because URLs have many 'inconveniences'.

function isValidUrl(str) {
    /* const pattern = new RegExp(
      '^(https?:\\/\\/)?' + // protocol
      '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|' + // domain name
      '((\\d{1,3}\\.){3}\\d{1,3}))' + // OR IP (v4) address
      '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*' + // port and path
      '(\\?[a-zA-Z\\&\\d%_.,~+-:@=;&]*)?' + // query string
      '(\\#[-a-z\\d_]*)?$', // fragment locator
      'i'
    ); */
    
    /* reference from https://stackoverflow.com/a/54620350/14344959*/
    const newModi = new RegExp(
       '^(https?:\\/\\/)?' + // protocol
       '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}' + // domain name
       '|((\\d{1,3}\\.){3}\\d{1,3})' + // OR IP (v4) address
       '|localhost)' + // OR localhost
       // '(\\:\\d+) + // port (one or more digits)
       '(\\:\\d{1,5})?' + // port (digits limit 1 to 5)
       // '(\\/[-a-z\\d%_.~+]*)*'+ // path
       '(\\/[a-zA-Z\\&\\d%_.~+-:@]*)*' + // path
       // '(\\?[;&a-z\\d%_.~+=-]*)?' + // query string
      '(\\?[a-zA-Z\\&\\d%_.,~+-:@=;&]*)?' + // query string
      // '(\\#[-a-z\\d_]*)?$', // fragment locator
      '(\\#[-a-zA-Z&\\d_]*)?$', // fragment locator
    );
    
    return newModi.test(str);
  }

Valid Url Cases:

  1. only domain name
  2. full url with fragment also
  3. if url doesn't contains http or https protocol
  4. if url doesn't contains 'www.' before the domain
  5. url has sub domain

Run Below Snippet or run on jsFiddle for see Output of this regex method.

in Snippet & jsFiddle link - even you can also compare the output of above regex way & URL() class (checked url is valid or not by URL class method)

I hope you like this...

:) Happy Coding!

function isValidUrl(str) {
    /* const pattern = new RegExp(
      '^(https?:\\/\\/)?' + // protocol
      '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|' + // domain name
      '((\\d{1,3}\\.){3}\\d{1,3}))' + // OR IP (v4) address
      '(\\:\\d+)?(\\/[-a-z\\d%_.~+]*)*' + // port and path
      '(\\?[a-zA-Z\\&\\d%_.,~+-:@=;&]*)?' + // query string
      '(\\#[-a-z\\d_]*)?$', // fragment locator
      'i'
    ); */
    
     /* reference from https://stackoverflow.com/a/54620350/14344959*/
    const newModi = new RegExp(
       '^(https?:\\/\\/)?' + // protocol
       '((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}' + // domain name
       '|((\\d{1,3}\\.){3}\\d{1,3})' + // OR IP (v4) address
       '|localhost)' + // OR localhost
       // '(\\:\\d+) + // port (one or more digits)
       '(\\:\\d{1,5})?' + // port (digits limit 1 to 5)
       // '(\\/[-a-z\\d%_.~+]*)*'+ // path
       '(\\/[a-zA-Z\\&\\d%_.~+-:@]*)*' + // path
       // '(\\?[;&a-z\\d%_.~+=-]*)?' + // query string
      '(\\?[a-zA-Z\\&\\d%_.,~+-:@=;&]*)?' + // query string
      // '(\\#[-a-z\\d_]*)?$', // fragment locator
      '(\\#[-a-zA-Z&\\d_]*)?$', // fragment locator
    );
    
    return newModi.test(str);
  }

const testLinks  = [
    ['test', false],
  ['test.com', true],
  ['http://test.com', true],
    ['www.test.com', true],
  ['http://www.test.com', true],
  ['test.com/products', true],
  ['help.test.com', true],
  ['www.help.test.com', true],
  ['http://example.com', true],
  ['https://www.example.com/path', true],
  ['www.example.com', true],
  ['example.com/path', true],
  ['example.com?query=param', true],
  ['ftp://example.com', false],
  ['http://192.168.0.1', true],
  ['http://192.168.0.1:8080', true],
  ['http://example.com#section', true],
  ['http://example.com:8080/path?query=param', true],
  ['/product/sas.png', false],
  ['?query=param', false],
  ['#section', false],
  ['http://example.com?param=123&name=John', true],
  ['http://example.com?param1=123&param2=456', true],
  ['https://example.com/path?query=param#section', true],
  ['?name=John&age=30', false],
  ['#section-content', false],
  ['http://example.com#', true],
  ['https://example.com/path?', true],
  ['', false], // Empty string 
  [null, false], // Null value 
  [undefined, false], // Undefined value 
  
  
  // additional urls
  ['http://en.wikipedia.org/wiki/Procter_&_Gamble', true],
  ['https://sdfasd', false],
  ['http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&docid=nIv5rk2GyP3hXM&tbnid=isiOkMe3nCtexM:&ved=0CAUQjRw&url=http%3A%2F%2Fanimalcrossing.wikia.com%2Fwiki%2FLion&ei=ygZXU_2fGKbMsQTf4YLgAQ&bvm=bv.65177938,d.aWc&psig=AFQjCNEpBfKnal9kU7Zu4n7RnEt2nerN4g&ust=1398298682009707', true],
  
  ['https://stackoverflow.com/', true],
  ['https://w', false],
  ['aaa', false],
  ['aaaa', false],
  ['oh.my', true],
  ['dfdsfdsfdfdsfsdfs', false],
  ['google.co.uk', true],
  '-hyphen-start.gov.tr',
  ['test-domain.MUSEUM', true],
  ['-hyphen-start.gov.tr', false],
  ['hyphen-end-.com', false],
  ['https://sdfasdp.international', true],
  ['https://sdfasdp.pppppppp', false],
  ['https://sdfasdp.ppppppppppppppppppp', false],
  ['https://sdfasd', false],
  ['https://sub1.1234.sub3.sub4.sub5.co.uk/?', true],
  ['http://www.google-com.123', false],
  ['http://my--testdomain.com', false],
  ['http://my2nd--testdomain.com', true],
  ['http://thingiverse.com/download:1894343', true],
  ['https://medium.com/@techytimo', true],
  ['http://localhost', true],
  ['localhost', true],
  ['localhost:8080', true],
  ['localhost:65536', true],
  ['localhost:80000', false],
  ['magnet:?xt=urn:btih:123', true],
  ['test:8080', false],
  ['test.com:8080', false],
];

const validUrlResults = [];

const resElem = document.getElementById('result');
var resStr = '';
testLinks.forEach((e) => {
    let testResult = isValidUrl(e[0]);
  if (testResult === true) {
    validUrlResults.push(e[0]);
  }
  
    resStr += '<li><span class="input">' + e[0] + '</span> <span class="outputBool">'+ testWithUrlClass(e[0]) + '</span> <span class="outputBool">'+ testResult + '</span>  <span>' + (testResult === e[1] ? 'passed' : 'failed') + '</span></li>';
});

resElem.innerHTML = resElem.innerHTML + resStr;

// console.log(validUrlResults);

/**
  * The given value must start with a protocol (e.g., http:// or https://)
  * If the value doesn't start with a protocol,
  * the function may return false.
*/
function testWithUrlClass(urlStr) {
    try {
    new URL(urlStr);
    return true;
  } catch(e) {
    return false;
  }
}
li {
  margin-bottom: 15px;
}
.input {
  display: inline-block;
  width: 40%;
  word-break: break-all;
}

.outputBool {
 display: inline-block;
  width: 15%;
}
<ul id="result">
  <li>
    <span class="input"><b>Inputs</b></span>
    <span class="outputBool"><b>With Url Class</b></span>
    <span class="outputBool"><b>With Regex</b></span>
    <span><b>Regex passed as Expected?</b></span>
  </li>
</ul>

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