For movie's we use
The Internet Movie Database (IMDb) Just last night my daughter was at a friends house and called home to see if she can watch a movie she was unsure about. (what a good kid

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We pulled it up on
IMDb looked for the link that said "Parents Guide: View content advisory for parents". It gives a very detailed description of sexual content, violence, profanity, alcohol/drugs/smoking, and frightening/intense scenes. We had to say no the first movie, but yes to the second.