Here is a jungle ranking of League of Legends.
Rules of jungle ranking:
Those champion can be treated as the king of jungling. They have a good performance in every aspect. If you want to handle the junlge, you should control one of these champion.
Those champion is not good as above champion. They only play good in some aspects.But they have some weakness. If you want to have a good performance, you should focus on their advantages.
Those champion is similar to Tier 2. The reason I put them in Tier 3 is that I consider champions of Tier 2 is updating from Tier 3.
Those champions are much weaker than above. Some of them born to not fit for jungle. They often are bullied in jungling.
They are specila from other tier. Those champion can jungle and they do not need special item. But those items will affect the later game, which can not be neglected.