Dog brains weigh anywhere between 50 to 130 grams. Smaller dog brains are about the size of a lemon, whereas the largest dog brains are similar in size to a small pear. The size of a dog’s brain is mostly related to the size of their body. Bigger dogs tend to have larger brains.
In comparison, the human brain weighs about 2.5 to 3 pounds. This is not only because humans tend to be bigger than dogs, but also because we have more brain tissue relative to our body size. But it is important to note that there is not an exact correspondence between brain size and intelligence. Human brains are special for additional reasons.