# When Do Dogs Stop Growing? Age by Breed Size When do dogs stop growing? Most small breeds finish growing between 6 and 12 months of age, medium breeds around 12 to 15 months, and large or giant breeds anywhere from 18 to 24 months. The exact answer depends on your dog's adult size, genetics, and early development. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Small breeds (under 20 pounds adult weight) usually reach their adult height by 6 to 9 months and fill out by 12 months. - Medium breeds (20 to 50 pounds) typically stop growing between 12 and 15 months. - Large and giant breeds (over 50 pounds) keep growing until 18 to 24 months, sometimes longer. - Growth plates close last, so your dog may look full height while still adding muscle and body condition. - Weigh your puppy every 2 weeks and track it against a growth chart from your veterinarian to spot problems early. ## How Puppy Growth Actually Works Puppies do not grow at one steady rate. They go through fast growth spurts in the first few months, then slow down as their bones mature. The first 120 days of life, counting pregnancy plus the first two months after birth, are the most critical window for development in dogs [1]. What happens during that window can shape your dog's adult body condition for years. Birth weight matters more than most owners realize. Low birth weight puppies have a higher risk of death in the first three weeks and a greater chance of becoming overweight as adults [1]. That said, the postnatal period offers a chance to offset some of those early risks. Puppies born small who catch up with good early growth have better outcomes [1]. For a single breed like the Dobermann, researchers found that both birth weight and weight on day one were influenced by the puppy's sex and maternal factors, and both were important for predicting survival and monitoring growth [2]. This tells us that early weight tracking is not just a nice extra. It is a real health tool. ## When Do Dogs Quit Growing? Age by Breed Size Here is a general comparison table. These are typical ranges, and your individual dog may fall outside them. | Breed Size | Adult Weight | Height Stops | Full Maturity | |---|---|---|---| | Toy (Chihuahua, Yorkie) | Under 10 lb | 6 to 8 months | 10 to 12 months | | Small (Beagle, Shih Tzu) | 10 to 20 lb | 8 to 10 months | 12 months | | Medium (Cocker Spaniel, Border Collie) | 20 to 50 lb | 10 to 14 months | 12 to 15 months | | Large (Labrador, German Shepherd) | 50 to 90 lb | 12 to 18 months | 18 to 24 months | | Giant (Great Dane, Mastiff) | Over 90 lb | 18 to 24 months | 24 to 30 months | Small dogs mature faster because their growth plates close sooner. Large dogs take longer because their bones have more growing to do. This is also why spay and neuter timing differs by size. You can read more about that in [When to Spay a Dog: Optimal Age for Small vs Large Breeds](/knowledge/veterinary-medicine/life-stage-emergency-care/when-to-spay-a-dog-optimal-age-for-small-vs-large-breeds). ## When Do Dogs Stop Being Puppies? Behavioral maturity and physical maturity are two different things. Your dog may stop growing in height at 10 months but still act like a puppy until age 2 or 3. Smaller breeds tend to settle down sooner. Larger breeds often stay playful and excitable well into their second year. If you are working on manners and obedience, the age-based approach matters. See [Puppy Training Guide By Age](/knowledge/veterinary-medicine/behavior/puppy-training-guide-by-age) for a stage-by-stage plan. ## Step-by-Step: How to Track Your Puppy's Growth 1. Weigh your puppy at the same time each day, ideally before the first meal. Use a kitchen scale for toy breeds and a bathroom scale (weigh yourself holding the puppy, then subtract your weight) for larger puppies. 2. Record the weight in a notebook or phone app. Write the date next to each number. 3. Measure height at the withers (the top of the shoulder blades) once a month. Use a wall and a ruler or a tape measure. 4. Compare your puppy's weight to a breed growth chart. Your veterinarian can provide one or point you to a reliable version. 5. Watch for the flattening of the growth curve. When weight gain slows to near zero for 4 to 6 weeks, your puppy is likely near adult size. 6. Take monthly photos from the same angle and distance. This gives you a visual record that is easy to compare. 7. Schedule a veterinary check at 6 months, 12 months, and 18 months to confirm growth is on track. ## Signs Something Is Wrong Stunted growth is not always obvious. Some puppies simply stay small because of genetics. Others have a medical problem that needs treatment. Watch for these signs: - Weight gain stops for more than 4 weeks before the expected maturity age. - Your puppy is much smaller than littermates at the same age. - You see lameness, limping, or reluctance to walk or play. - The body looks disproportionate, such as a large head on a tiny body. - Your puppy tires easily or seems weak during normal activity. - You notice vomiting, diarrhea, or poor appetite lasting more than 2 days. - The coat looks dull or your puppy has patchy hair loss. Some of these signs can point to developmental issues. For example, congenital vertebral anomalies can affect how a dog's spine forms and may influence growth and movement [3]. A veterinarian can assess whether your puppy's growth pattern is normal for its breed and age. ## Common Mistakes Owners Make **Comparing your puppy to a different breed.** A Labrador puppy will always outweigh a Beagle puppy of the same age. Compare within the same breed or size category. **Assuming a puppy is done growing because height stopped.** Height is only one measure. Your dog continues to add muscle and body condition for months after the growth plates close. **Overfeeding to speed up growth.** Faster growth is not healthier growth. Large breed puppies on high-calorie diets can develop joint problems. Feed a diet formulated for your puppy's expected adult size. **Skipping early weight checks.** Birth weight and early weight changes are important for predicting survival and monitoring growth [2]. If you got your puppy from a breeder, ask for the birth weight and early weight records. **Ignoring low birth weight history.** Puppies born small have a higher risk of becoming overweight as adults [1]. If your dog was a low birth weight puppy, keep a closer eye on body condition through adulthood. **Waiting too long to see a vet.** If your puppy's growth stalls, do not wait to see if it catches up on its own. Early evaluation gives you more options. ## Supplies and Setup That Matter for Growth Monitoring You do not need much to track your puppy's growth well. Here is what helps: - A digital scale accurate to 0.1 lb for toy and small breeds. - A bathroom scale for medium and large puppies. - A soft tape measure for height and chest girth. - A notebook or a phone app for logging weights and dates. - A growth chart specific to your breed or size category. - A calendar reminder every 2 weeks for weigh-ins. - A measuring spot against a wall with a mark at your puppy's shoulder height. Keep the setup simple. The goal is consistency, not perfection. Weighing at the same time of day and using the same scale gives you the most reliable trend. ## How Growth Ties to Long-Term Health Growth rate and adult size affect how long your dog may live. In general, smaller dogs live longer than giant breeds. You can read more about typical lifespans in [How Long Do Dogs Live](/knowledge/veterinary-medicine/clinical-methods/how-long-do-dogs-live). Body condition at maturity also matters. A dog that finishes growing at a healthy weight has a lower risk of joint stress and metabolic problems later. If your dog was a low birth weight puppy, the risk of adult overweight is higher [1], so portion control and regular exercise become even more important. Some breeds have specific developmental conditions that can affect growth. For example, Alopecia X is a hair cycle disorder common in Pomeranians and other plush-coated breeds, and it is not linked to low IGF-1 levels in the way researchers once thought [4]. While this condition does not affect height, it shows how breed-specific health issues can appear during or after the growth period. ## Limitations and When to Contact a Veterinarian No article can tell you whether your individual puppy is growing normally. Your veterinarian needs to examine your dog, review its weight history, and consider breed, genetics, and overall health. Contact your veterinarian the same day if: - Your puppy has not gained weight in 4 or more weeks before the expected maturity age. - You see sudden lameness or your puppy refuses to bear weight on a leg. - Your puppy has vomiting or diarrhea that lasts more than 24 hours. - Your puppy's appetite drops sharply or stops completely for more than one day. Go to an emergency clinic now if: - Your puppy collapses, has trouble breathing, or seems unresponsive. - You see seizures or severe trembling. - Your puppy has a swollen, painful abdomen that feels hard to the touch. - There is heavy bleeding or a suspected fracture. Schedule a routine visit if: - You want to confirm your puppy's growth is on track for its breed. - You need a breed-specific growth chart. - You have questions about diet, spay or neuter timing, or exercise limits during growth. - Your puppy was a low birth weight and you want a long-term health plan. ## Frequently Asked Questions ### Do dogs stop growing at 1 year? Most small and medium breeds are close to their adult size by 12 months, but large and giant breeds keep growing well past that. A Great Dane may not finish until 24 to 30 months. Always consider your dog's breed size before assuming growth is done. ### Can a puppy be stunted and still healthy? Yes, some puppies are genetically smaller and remain healthy. But stunted growth caused by nutrition, parasites, or disease needs veterinary attention. A vet can tell the difference with a physical exam and weight history. ### Does neutering affect when a dog stops growing? Neutering timing can influence growth plate closure, especially in large breeds. Talk to your veterinarian about the best age for your dog's size and breed. The decision balances growth, behavior, and cancer risk. ### How can I tell if my puppy is still growing? Measure height at the shoulder and weight every 2 to 4 weeks. If both numbers have been stable for 4 to 6 weeks, your puppy is likely near adult size. Your vet can confirm with a physical exam. ### What if my puppy is much smaller than its littermates? A puppy that is significantly smaller may have had a low birth weight or an early health issue. Low birth weight puppies face higher risks in the first weeks and a greater chance of adult overweight [1]. Ask your vet to evaluate growth and rule out underlying problems. ## Related Articles - [When to Spay a Dog: Optimal Age for Small vs Large Breeds](/knowledge/veterinary-medicine/life-stage-emergency-care/when-to-spay-a-dog-optimal-age-for-small-vs-large-breeds) - [How Long Do Dogs Live](/knowledge/veterinary-medicine/clinical-methods/how-long-do-dogs-live) - [Puppy Training Guide By Age](/knowledge/veterinary-medicine/behavior/puppy-training-guide-by-age) - [How Long Do Dogs Live For](/knowledge/veterinary-medicine/clinical-methods/how-long-do-dogs-live-for) - [How Long Do Dogs Stay Pregnant](/knowledge/veterinary-medicine/clinical-methods/how-long-do-dogs-stay-pregnant) - [How Long Does A Dog Period Last](/knowledge/veterinary-medicine/clinical-methods/how-long-does-a-dog-period-last) ## References 1. [Developmental programming in dogs](https://pubmed.ncbi.nlm.nih.gov/42384936/). Biology of reproduction, 2026. 2. [Birth Weight and Early Weight Changes in Newborn Dogs: Analyzing Key Influencing Factors in Dobermann Puppies](https://pubmed.ncbi.nlm.nih.gov/42121829/). Animals : an open access journal from MDPI, 2026. 3. [Congenital and Breed-Associated Vertebral Anomalies in Dogs and Cats: Developmental Anatomy, Genetic Determinants, and Biological Significance](https://pubmed.ncbi.nlm.nih.gov/42795408/). Life (Basel, Switzerland), 2026. 4. [Serum insulin-like growth factor-1 concentrations are not reduced in Pomeranian dogs with Alopecia X: a case-control study](https://pubmed.ncbi.nlm.nih.gov/42443886/). BMC veterinary research, 2026. ## Further Reading - [Merck Veterinary Manual: Dog Owners](https://www.merckvetmanual.com/dog-owners) - [Cornell Richard P. Riney Canine Health Center: Canine Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center/canine-health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)