How Do Cats' and Dogs' Sense of Smell Compare to that of a Human?

A cat's sense of smell is 14 times more powerful than that of a human.

Cats’ and dogs’ senses of smell are much greater than that of human
beings. In fact, a cat’s sense of smell is estimated to be 14 times
stronger than the average human's, and a dog’s sense of smell is thought
to range from 1,000 to 1 million times more powerful than a human's.
Olfactory receptors are proteins that are located within the nose and are
responsible for helping the brain process odors. The average human nose
contains 5 million olfactory receptors, and cats' noses have as many as 80
million. Dogs’ noses are thought to contain as many as 300 million
olfactory receptors.
Read More: http://www.wisegeek.com/how-do-cats-and-dogs-sense-of-smell-compare-to-that-of-a-human.htm?m