^ (?i) # apply this regex in a case-insensitive manner. # One or more dot-separated parts . . . (?: [a-z0-9]\. | [a-z0-9][-a-z0-9]*[a-z0-9]\. )+ # Followed by the final suffix part . . . (?: com|edu|gov|int|mil|net|org|biz|info|name|museum|coop|aero|[a-z][a-z] ) $ ----------------------------------------------------------------------------- Copyright 1997-2024 Jeffrey Friedl