Screenit is a site that has been online for at least two decades. The service they offer is a breakdown of movie content. You search for a movie, and screenit will provide a breakdown of any and all content that may be questionable for young viewers. It offers a free three-day trial. Newly released movies are often listed on their homepage for free.
The site offers a graph view of many movies, and then gives detailed descriptions for each identified category of content as shown in the graph below.