Not to be rude but i'd like only educated answers, meaning people who actually know that arn't just guessing. Thanks a million.

Chihuahua, but bad breeding results of "Teacup" dogs which can be smaller the 2lbs full grown

I'm quite sure that the smallest breed of dog in the world is a Chihuahua. A full-grown Chihuahua will be 6 to 9 inches tall and will weigh 2 to 6 pounds. Hope that helps =)

proably a miniture pinscher

A teacup chihuahua is the smallest I've seen so far. Its so tiny, you need to becareful where you walk, or you could accidentally step and crush the little fella!

The Prazky Krysarik, or Prague Ratter, is the worlds smallest dog. We had a client who bought two to breed from Poland and they were never supposed to get over 1 1/2 pounds but the girl got 3 pounds and the boy was only 1 pound.