How To Get Redirect URL In PHP

HTTP redirects usually have the response status 301 or 302 and provide the redirection URL in the “Location” header. I’ve written three complementary PHP functions that you can use to find out where an URL redirects to (based on a helpful thread at WebmasterWorld). You don’t even need CURL for this – fsockopen() will do just fine.

The PHP script

/**
 * get_redirect_url()
 * Gets the address that the provided URL redirects to,
 * or FALSE if there's no redirect. 
 *
 * @param string $url
 * @return string
 */
function get_redirect_url($url){
	$redirect_url = null; 

	$url_parts = @parse_url($url);
	if (!$url_parts) return false;
	if (!isset($url_parts['host'])) return false; //can't process relative URLs
	if (!isset($url_parts['path'])) $url_parts['path'] = '/';
	 
	$sock = fsockopen($url_parts['host'], (isset($url_parts['port']) ? (int)$url_parts['port'] : 80), $errno, $errstr, 30);
	if (!$sock) return false;
	 
	$request = "HEAD " . $url_parts['path'] . (isset($url_parts['query']) ? '?'.$url_parts['query'] : '') . " HTTP/1.1\r\n"; 
	$request .= 'Host: ' . $url_parts['host'] . "\r\n"; 
	$request .= "Connection: Close\r\n\r\n"; 
	fwrite($sock, $request);
	$response = '';
	while(!feof($sock)) $response .= fread($sock, 8192);
	fclose($sock);

	if (preg_match('/^Location: (.+?)$/m', $response, $matches)){
		if ( substr($matches[1], 0, 1) == "/" )
			return $url_parts['scheme'] . "://" . $url_parts['host'] . trim($matches[1]);
		else
			return trim($matches[1]);
 
	} else {
		return false;
	}
	
}

/**
 * get_all_redirects()
 * Follows and collects all redirects, in order, for the given URL. 
 *
 * @param string $url
 * @return array
 */
function get_all_redirects($url){
	$redirects = array();
	while ($newurl = get_redirect_url($url)){
		if (in_array($newurl, $redirects)){
			break;
		}
		$redirects[] = $newurl;
		$url = $newurl;
	}
	return $redirects;
}

/**
 * get_final_url()
 * Gets the address that the URL ultimately leads to. 
 * Returns $url itself if it isn't a redirect.
 *
 * @param string $url
 * @return string
 */
function get_final_url($url){
	$redirects = get_all_redirects($url);
	if (count($redirects)>0){
		return array_pop($redirects);
	} else {
		return $url;
	}
}

Here’s an example that lists all URLs that a given address redirects to (in order) :

$rez = get_all_redirects('http://daerils.gtrends.hop.clickbank.net/');
print_r($rez);

Known Issues

Most likely you won’t ever run into one of these, but here they are anyway :

The script doesn’t recognize infinite redirects that don’t form a loop. However, it can handle normal redirection loops – get_all_redirects() exits as soon as it encounters an URL that it has already seen.
Relative redirects multiple (e.g. “Location: go.php?asdf”) won’t be fully followed by get_all_redirects().
Not an issue per-se, yet something to note : these functions won’t tell you if an URL is valid, just what it redirects to (if anything).

On a related note, check out the Firefox extension Redirect Remover.

Related posts :

This entry was posted on Saturday, July 5th, 2008 at 23:54 and is filed under Web Development. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

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66 Responses to “How To Get Redirect URL In PHP”

Sadik says:

August 28, 2010 at 09:25

Thanks a million… You saved me the coding 🙂
Ravishankar says:

September 24, 2010 at 13:14

Returning back to comment 26 above my Manish, the URL he mentions consists of (note the secure protocol) https://…..

So, if the URL contains https://, the above codes does not seem to work. I’m facing the same issue.. any help?

Ravi.
White Shadow says:

September 26, 2010 at 23:06

To check HTTPS URLs, you would need to rewrite the script to use something like curl.
Itzekocke says:

April 11, 2011 at 10:26

Thanks,

that little function helped a lot!

Itzekocke
Johnny Tsunami says:

April 13, 2011 at 12:55

Good stuff! You helped me, too.
Prasenjit Das says:

July 1, 2011 at 12:46

This helps me a lot.Many thanks.
Ruth says:

August 24, 2011 at 14:32

Hi
Worked for many sites, but did not work for http://www.oldcastle.com/.
Can anyone find a solution for this.
Thanks,
Ruth.
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September 17, 2011 at 04:03

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Michel says:

October 4, 2011 at 18:14

This script works great!
Only thing I was wondering is, if it is possible to check the final url with the given redirected url.

Let me give an example:

I want example.com/1
To redirect to example.com/2

With this script I created that I can manually check if the url is correct. But if I have a lot more redirects to check, I would like to handle that automatically like:

I redirected it to example.com/2 now when I run this script, what I would like it to do.

I give an array with the redirect from urls (example.com/1)
And at the check I want it to check if example.com/1 really does go to example.com/2.

I’m not really an expert in PHP so I hope you can give an answer.

Thanks,
Michel
Christoph says:

April 22, 2012 at 15:07

Thanks!

I’ve need it for my new Facebook App… 🙂
Alex says:

July 5, 2012 at 12:34

THANKS … very thanks
Khoa NĐ says:

September 13, 2012 at 11:14

Thanks. It’s amazing.
Andre says:

November 17, 2012 at 16:55

It doesn’t work with ampersands in the url.
Lennart says:

December 16, 2012 at 16:11

To use with ampersands urlencode the URL first.
Neues Projekt: SerienjunkiesCollector | StefanFabian.ME - Blog - DE says:

February 6, 2013 at 00:24

[…] PHP REDIRECT Decoder […]
How to get final URL after following HTTP redirections in pure PHP? - PHP Solutions - Developers Q & A says:

September 22, 2013 at 11:43

[…] http://w-shadow.com/blog/2008/07/05/how-to-get-redirect-url-in-php/ […]
romuald says:

February 23, 2014 at 17:13

I do a cmd c cmd v run it ! it works !

BIG THANKS

Rafael says:

April 22, 2014 at 03:54

I needed to handle https, and did not have to change much in the function:

function get_redirect_url($url){
    $redirect_url = null; 

    $url_parts = @parse_url($url);
    if (!$url_parts) return false;
    if (!isset($url_parts['host'])) return false; //can't process relative URLs
    if (!isset($url_parts['path'])) $url_parts['path'] = '/';
	$url_host = $url_parts['host'];
	if (isset($url_parts['scheme']) &amp;&amp; $url_parts['scheme'] == 'https') {
		$url_host = 'ssl://' . $url_host;
		$url_default_port = 443;
	} else {
		$url_default_port = 80;
	}
    $sock = fsockopen($url_host, (isset($url_parts['port']) ? (int)$url_parts['port'] : $url_default_port), $errno, $errstr, 30);
    if (!$sock) return false;

    $request = &quot;HEAD &quot; . $url_parts['path'] . (isset($url_parts['query']) ? '?'.$url_parts['query'] : '') . &quot; HTTP/1.1\r\n&quot;; 
    $request .= 'Host: ' . $url_parts['host'] . &quot;\r\n&quot;; 
    $request .= &quot;Connection: Close\r\n\r\n&quot;; 
    fwrite($sock, $request);
    $response = '';
    while(!feof($sock)) $response .= fread($sock, 8192);
    fclose($sock);

    if (preg_match('/^Location: (.+?)$/m', $response, $matches)){
        if ( substr($matches[1], 0, 1) == &quot;/&quot; )
            return $url_parts['scheme'] . &quot;://&quot; . $url_parts['host'] . trim($matches[1]);
        else
            return trim($matches[1]);

    } else {
        return false;
    }

}

I did have curl and openssl enabled, mind you.

Otyan Mckiny says:

March 11, 2015 at 10:10

Also it handle https request, i tried it on 2 differen php type websites and redirection url is not a problem on them.
planetslagu says:

August 17, 2017 at 16:25

how create redirect at get

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