The average cow's brain is approximately the size of a baseball and weighs between 425 to 458 grams, which is a little under one pound. A cow's brain is only about 0.1 percent of its total body weight.
The brain of a steer weighs more on average than regular cows and bulls, topping out at 94 grams per 100 kilograms of body weight. The average of cows is around 85 grams per 100 kilograms of weight. A human brain weighs almost three times as much as a cow's brain, averaging between 1.3 and 1.4 kilograms. The weight of a cow's cerebellum alone is approximately 35.7 grams on average.