Check if there's consecutive chars

Check if first char is 0 followed by 9 digits

substring

matches the http portion of a url, both http:// and https://, and also matches the www. portion if that is included.

It is not compatible with leet speak, you can replace all numbers with their letter counterparts before matching the string with regex.

Regular expression ^(?:https?:)?(?:\/\/)?(?:+@)?(?:www\.)?(+) used below extracts domain with subdomains out of a full url. It skips protocol (ex: https:), "//", "@", www subdomain and then captures everything (ex: domain) before ":" or "/" or end of line.