How to get the domain name without www, subdomain, and com/net/org/etc

Question

I just need to get the domain name only form a url, (without com and everything else) example:

I have:

http://www.subdomain.domain1.com/
www.subdomain.domain2.net
subdomain.subdomain2.domain3.org/
http://domain4.com

I want to get with PHP:

domain1
domain2
domain3
domain4

Solution 1

parse_url()

with the "PHP_URL_HOST" argument

then explode() on the "." and extract the penultimate element of the resulting array

Solution 2

Building off of Shyam's answer and employing the concept suggested by Mark Baker to get the penultimate element of the namespace, I might suggest using a simpler regular expression that utilizes an anchored lookahead like the following:

function get_domain($url) {
    $matches = [];
    preg_match('/[\w-]+(?=(?:\.\w{2,6}){1,2}(?:\/|$))/', $url, $matches);
    return $matches[0];
}

Matches

• names in https://www.names.co.uk/
• domain1 in http://www.subdomain.domain1.com/
• domain2 in www.subdomain.domain2.net
• domain3 in subdomain.subdomain2.domain3.org/
• domain4 in http://domain4.com
• seventymm in http://www.seventymm.co.in/browse/buy-home-furnishing-bed-sheets-pack-of-3/2456/1/v2034/0/0/1/2/1/0/go

Comments

[user1502679]

But how to get the penultimate element? so I can update the post with the solution. Thanks!

[Decent Dabbler]

Be aware of possible urls with top level domains such as .co.uk (are those officially called top level as well, by the way?), etc., though.

[Carlos]

@fireeyedboy Very good point!

[Syntax Error]

This is not a flexible solution - it only works when the subdomain is known.

[Wernight]

It'll also not work if you have only the IP.