Is there an official site for anime and manga ranking? Is there any official site for anime and manga ranking? I know some site for anime and manga, and they have some kind of rating and ranking, but their rating and ranking are different. I'm wondering if there are any official site for anime, maybe something like IMDB? Honestly, I don't really know if IMDB is official or not, but if someone is to ask for the rating of a movie, they always say to look it in IMDB.
As far as I know there is no official ranking site for anime/manga.

The closest thing you could get to an official ranking would be ranking them according to their sales, which gets featured on a lot of sites. An example would be this MyAnimeList post. More info and sites can be found on the post Where can one learn about viewership ratings for anime?, where some nice sites have been listed.

Most other rating sites are, as hungerartist mentioned, user rated and therefore not official.