Literally the best list on Letterboxd.
The 50 Greatest Cartoons: As Selected by 1,000 Animation Professionals is a 1994 book by animation historian Jerry Beck. It consists of articles about 50 highly regarded animated short films made in North America and other notable cartoons, which are ranked according to a poll of 1,000 people working in the animation industry. In addition to the main list, the book also recommends other cartoons that were nominated for the main list.
I love cartoons.
#1-50 are ranked.
#51+ are the runners-up, listed in alphabetical order.