The heart rate in dogs is different from humans, the only similarity being that it increases with activities and decreases when relaxed. The pulse rate of the heartbeat rate of your dog’s heart depends upon its size. It’s 60 to 100 beats per minute in large dogs, while the smaller dogs have 100 to 140 beats per minute. In puppies, the heartbeat is much more rapid and can range from 160 to 200 beats per minute.