Extracting top-level and second-level domain from a URL using regex

Question

How can I extract only top-level and second-level domain from a URL using regex? I want to skip all lower level domains. Any ideas?

Answer 1

Also, you can likely do that with some expression similar to,

^(?:https?:\/\/)(?:w{3}\.)?.*?([^.\r\n\/]+\.)([^.\r\n\/]+\.[^.\r\n\/]{2,6}(?:\.[^.\r\n\/]{2,6})?).*$

and add as much as capturing groups that you want to capture the components of a URL.

Demo

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If you wish to simplify/modify/explore the expression, it's been explained on the top right panel of regex101.com. If you'd like, you can also watch in this link, how it would match against some sample inputs.

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RegEx Circuit

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