An average full-grown cow weighs between 1,000 and 1,800 pounds. A cow's weight varies by breed, age and individual factors. Holstein dairy cows tend to be quite large and usually weigh around 1,500 pounds, while Jersey dairy cows are smaller and usually weigh around 1,000 pounds when full grown.
Angus beef cattle weigh around 1,200 pounds at slaughter weight. A full-grown Angus bull can weigh as much as 2,000 pounds. The largest breed of cow in the world, the Chianina, can weigh over 3,800 pounds at maturity. One of the smallest breeds of cow in the world, the Dexter miniature cow, only weighs 600 to 700 pounds at maturity.