6/10 Many episodes contain uses of words like fricking, bitch, bastard, crap, ass, damn, god, dick, hell, retard and slut.
'Shite' (British equivalent of 'shit') is used by the school's groundskeeper very infrequently in the fifteenth season. In Britain, this is omitted from television broadcast.
There are uses of bullshit, whore and fuck, but they are censored on TV
The character of Ned Flanders may be considered as a mockery of Christianity. There are many jokes and mockeries of religious themes (mainly Christian, some Jewish, Buddhist and Hindu) that some may consider rude.
A few mild racial slurs. Frequent parodies of various cultures (somewhat offensive but still funny), including American, British, Irish, Scottish, French, Hispanic, Italian, Russian, Chinese, Japanese, Jewish and Australian. Ethnic and religious stereotypes are used and abused. They are not used in racist ways but rather sacrilegious ways.