A puppy growth calculator can do the calculations for you. Search online for a puppy growth calculator, enter your dog’s age in weeks and their weight, and find out whether your dog will be small, medium, or large. It’s important to remember that these calculations are just here to give you an estimate. Some dogs don’t reach their adult size until a year and a half or more, so this calculation is not 100% accurate.

Small dogs are 20 pounds (9. 1 kg) and below. At 6 months, these dogs are 75% grown. They usually reach their full size by 9-12 months. Medium dogs are between 21–50 pounds (9. 5–22. 7 kg). At 6 months, these pups are 66% grown (a little over halfway to their full size). They’ll reach their adult size by 12-15 months. Large dogs are between 51–100 pounds (23–45 kg). At 6 months, large puppies are 60% grown. They take longer to reach their full size, reaching adulthood between the ages of 15 to 18 months. Giant dogs are 100 pounds (45 kg) and above. At 6 months, giant dogs are 50% grown. They’ll reach their full size at about 18 months.

An example of a dog’s characteristics would be “short muzzle, curled tail, short and floppy ears, smooth and short coat, tan fur, and muscular build. " The above example would likely be a pug/bulldog mix, so their adult size would range between the size of a pug and a bulldog (A. K. A. small to medium).

Though paw size can help you make an estimate, it’s important to remember that some dog breeds naturally have large or small paws for their body (even in adulthood). These breeds include collies and bulldogs.

If you’re not sure how to feel for the knobs of your dog’s ribcage, ask your vet to do an examination next time you take them in for a checkup.

Dogs like bloodhound mixes and basset hound mixes usually have saggy skin as fully grown adult dogs.

If they don’t know the breed, but know the size, that can still be a good indicator of how big your puppy will get.

At-home DNA tests range from about $60 to $100. To find an accurate, good-quality test, read the reviews of each test online. These can help you determine how satisfied customers were with the results.