Animal Companion level

[Calantyr]

Simple question: Is the level of your Animal Companion based on the class level of the class that gave you the feat, or total caster level?

For example, is it worth getting the Animal domain if you're not going to have more than 20 levels in cleric, but still have a caster level of 30+?

[Nyeleni]

The class level. With a cleric 20 you will have a weaker animal companion than with a pure cleric at lvl 30 with the animal domain.

[metaquad4]

Ranger (-3 Levels), Cleric (with animal domain), Hierophant (with a feat it can get), Cavestalker and Druid all progress animal companion levels. You can make up 3 levels with natural bond, as well.

[Egg Shen]

So, what level companion would a cleric (animal) 11, heirophant 10, ranger 6, monk 3 with natural bond end up at? 27? Or would it be 3 different wimpy companions?

[Nyeleni]

Level from different classes do stack. Assuming Hierophant does progress it too this would give you an animal companion from a pure druid at lvl 24 (Cleric + Hierophant + Ranger -3).

Keep in mind that the companion only progresses every three levels of the character class (with progression in it).

So if I'm not wrong this should give you a lvl 17 companion. Which you can boost with natural bond and epic animal companion for a lvl 21.