How can you tell if a puppy will be big? Tips and Tricks

What If You Don’t Know The Breed?

How big will my mixed-breed puppy get? Well, this is more complicated if you have a mixed breed or don’t know the breed makeup of your dog. In the latter case, you can always consider doing a dog DNA test to determine his breed makeup (you’ll want to do a DNA test ASAP since results can take a few weeks).

Also, if you adopt a puppy from a shelter, they may be able to give you some idea of the suspected breed makeup.

However, the larger the dog breed, the more months they grow for…makes sense really. So first think about whether your pup is a toy, small, medium, large, or giant breed. Those at the pocket-sized end of the scale usually reach adult size as early as six months of age, whilst an out-sized giant dog carries on growing for 18 – 24 months.

Firstly, if your dog had puppies, an average newborn doubles their birthweight by one week of age. After that, their weight gain is a cumulative 5 – 10 % increase day on day.

If your Great Dane pup is growing faster than Japanese knotweed, you may be hoping that he’ll soon stop growing.

The first insight into their ultimate adult weight again comes at six weeks of age. Simply take their six-week weight, double it, and then double it again. For example, a 1 lb. puppy at six weeks old will weigh around 4lb as an adult.

Welcoming the patter of tiny paws into your home is an exciting time, but do you wonder how big the owner of those paws will become? (jump to Calculator)

How Big Will My Puppy Get?

In general, an adult average-sized dog at 12 months old weighs about 2-1/2 times their weight at 14 weeks or twice their weight at four months of age. But these are over-generalized estimates that don’t take some other factors into account, including:

  • Breed: Dogs’ growth rates and full-grown size vary widely by breed type. See our section below that breaks down breed sizes.
  • Parents: If you’re lucky enough to see your puppy’s parents, you can get a pretty good idea of how big your puppy will get based on their sizes.
  • Gender: As with humans, male puppies will typically be larger than females.
  • Neutering/Spaying: Puppies that are neutered or spayed early can weigh a bit more and be slightly taller than average as adults. Why? The procedure can somewhat alter the chemical signals that tell the body to stop growing on its normal path.
  • Can you tell how big a puppy will get?

    Whether we are shopping for a pet door, a dog bed, or just wondering, we have lots of questions about our dogs size. How big will my furry friend get as they become fully grown? When do puppies stop growing? How big will my adult dog get? Are puppy weight calculators even accurate?

    These questions arent easily answered by a quick Google search, especially if you have a mixed breed puppy (you typically know what youre going to get with a purebred puppy). Measurements like your puppys weight and paw size can help you predict their adult-size. However, dog breeds are not all made equal– small breeds, medium breeds, large breeds, and giant breeds all mature at different paces.

    Theres a lot of variation that can impact how big your little puppy with get. While predicting a puppys adult weight and height is not an exact science, there are a few ways to predict future growth and estimated full size with reasonable confidence.

    The free website is a neat way to predict your puppys adult weight by comparing their current size with historical data of other dogs from the same breed. This means that dogs from larger breeds will be ranked against their own breed while small dogs like terriers will be ranked against other terriers.

    While the tool isnt an exact indication of what your puppys adult size will be, its a fun way to at least get in the ballpark! Factors such as differing height and weight gain are not reflected in the weight calculator (or adult height), so its important to keep in mind that its not a comprehensive indication of your dogs specific growth rate, and could change for naturally larger dogs.

    Puppies are officially considered adults when they are one year old, but dogs can continue growing past that mark. Depending on your dog’s breed, your puppy will stop growing when they are anywhere from six to 24 months old.

    There isn’t a lot that be done to transform a lapdog into a German Shepherd, but there are a few factors beyond genetics that can affect how big your puppy will grow up to be:

    Generally, you can predict how big your dog will be based on their breed. But this may get hardened if they are a mutt. Luckily, if your dog is a mix between two breeds from the same weight range, you can usually depend on them falling in that weight range as well.

    Lets put the puppy growth calculator to the test! As curious pet parents, weve weighed our border collie puppy Mikey frequently since getting her in July so we can look into how quickly PuppyChart’s projection stabilizes.

    When we first took Mikey home, she was only an 8.2lb ball of fluff and cuteness. At that number of weeks (57 days), PuppyChart predicted she would be only 29.3 lbs at maturity, which is a bit on the smaller end for her pooch breed. Remarkably, even though we weighed Mikey 26 more times her PuppyChart projection remained largely consistent, fluctuating between 28.9 and 33.6 lbs and usually in the 31-32 range as shown in red in the graph below.

    Mikey’s still only a little over 5 months and still has some more growing to do, but so far it really looks like she’s headed to become about 32 lbs. The PuppyChart projection means that even at only 8 weeks, you can get a pretty good idea of how big your dog will grow. What a great way to see how big my dog would get. Now I know what size of dog door, bed, and crate to get for Mikey!

    Well, that’s a bit harder. You could probably average the puppy growth chart projections based on each breed component to get an idea. Another fun thing you could do with rescues is to work backward to figure your dog’s actual birthday. If you rescued a dog that was only 20 lbs and later grew to be 65 lbs, you can work backward to extrapolate that your puppy was about 11 weeks when you got her!

    Dog weight calculator - how big will my dog get and when do dogs stop growing? Looking for an alternative weight calculator? The American Kennel Club has a breed weight chart for a huge list of small dogs and large dogs (from Chihuahuas and Beagles to Mastiffs and Great Danes). This chart is a nice quick way to see just how big dogs can get!

    Did you do this test or another method? What do you think is the best dog-size calculator? Tell us your thoughts!

    Predicting your puppys size as an adult isnt just for fun as it can be necessary when buying things like dog beds, dog food, or pet doors. has dozens of brands of pet doors for every breed and every installation type.

    CEO DOG PERSON Pets: I have a half border collie, half angel named Mikey. Fun stuff: My dogs tongue is slightly longer than her face, so frequently her tongue sticks out a little even when her mouth is closed.

    CEO DOG PERSON Pets: I have a half border collie, half angel named Mikey. Fun stuff: My dogs tongue is slightly longer than her face, so frequently her tongue sticks out a little even when her mouth is closed.