How much bigger will my English Mastiff Heeler mix puppy get?

Zeus is a puppy, and he's going to continue to grow during the first year of his life. The good news is that his growth will slow down. Fully grown, Zeus can weight up to 66 pounds, and at around five months of age, he should be getting close to 3/4s of his full grown weight. The only thing you can do is keep feeding him puppy food according to the package instructions, and make sure he exercises for 25 minutes a day twice a day :-)

Atlas is a very handsome boy, congrats on your new dog! At seven months old, he will be getting close to his full size, and while he will grow some more (dogs typically reach adult size between one year to 18 months of age), he won't double in size from where he is currently. I would expect a little more growth from him but not a massive change in size or weight :-)

Based on the mix of breeds you said I would suspect that Gracie has done the majority of her growth already. You might see some very small amounts of growth until 18 months of age but for the most part she will hopefully remain that size forever.

Grown up size of a doog depends on genetics and nutrition. You can help your dog grow to his full potential by feeding him a good quality complete puppy food for large dogs. Some dogs will stay on the smaller side within the breed sprectrum. This does not take away from them. You do not want to make your dog grow taller faster than nature wants him to grow, as you make him prone to bone problems. Your dog will still grow for about another year to 18 months. Be patient.

I'm not sure if you meant to ask "when" boxer mix dogs are full grown, or how large they are? I would consider a medium-sized breed like a boxer mix to be full grown at around 12 months of age. As far as size, Boxers are medium-sized dogs that usually weigh around 60 lbs or so. Depending on what Chloe is mixed with, she might be this size as an adult, or could be a bit larger or smaller.

At 13 months of age, Yoda may grow just a bit more, but he is mostly done growing. Some dogs are just smaller in stature than others, regardless of having the same genetic background. It is unusual that Yoda (being a male) is smaller than his sister, but genes can do crazy things. Sixty pounds of muscle is still a pretty big dog! :-)

How sweet Apollo looks--what a nice dog! If he is 4 months old, he probably has about 40-50% more growing to do. The size of his paws will help give an idea how big he's likely to be, but there is no way to know for sure. I suspect somewhere around 80-120 lbs, but that's just a guess. Enjoy him!