There are a bunch of them, but as @zdanko mentioned, the IUCN Red List is the most widely used one.
That said, my experiences working with the Red List and trying to get species descriptions and classifications updated shows pretty clearly that the Red List is riddled with outdated information.
The Red List is also quite deficient when it comes to plants, gastropods, arthropods, and marine life in general. This is largely due to the difficulties in collecting data at the accuracy level needed to properly evaluate the species, to a lack of people researching certain species in certain areas, and a lack of people doing the necessary species evaluations even in the case the data exists.
Despite my criticisms of it, it’s still the best that’s out there, but for any particular species make sure to check the dates for the last time it was updated, and check with individuals who are working with species in question for the most up-to-date information.