Chihuahuas are one of the most popular dog breeds worldwide; the most prominent feature that makes them popular is their size. Despite being the smallest dog breed in the world, Chihuahuas are sassy, charming, and have a big personality.
Chihuahuas continue to grow until they are around ten to 12 months of age. Within the first few weeks of development, Chihuahuas grow quickly, doubling in size during this period. Most Chihuahuas reach their full adult weight and height within nine months.
One important thing to know about Chihuahuas is that if the dog gains any significant weight after it has reached its full weight, it is caused by various health problems or overfeeding.
When Do Chihuahuas Stop Growing?
Chihuahuas stop growing around the age of one year, so your dog should be fully grown when it is between ten to 12 months old. Chihuahuas do not grow taller than they get when fully matured; although they might add weight, it is not a sign of development; it depends on their activity level and diet.
Fully grown Chihuahuas can weigh about six pounds; the smallest Chihuahuas (Teacup Chihuahuas) are as small as four pounds. So, you know that a Chihuahua that weighs more than six pounds is either not purebred or is overweight. Some Chihuahuas weigh over 12 pounds and more.
There is a way professionals can guess how big a Chihuahua will get. When the dog is six months old, measure its height, multiply the number by 100, and divide the answer by 75. For example, if your Chihuahua weighs about 4.5 inches at six months old, multiply 4.5 by 100, that is 450; divide 450 by 75, that is 6 inches.
Factors Affecting Chihuahuas Growth Rate
As a Chihuahua owner, you should know that some factors affect the growth rate of your Chihuahua, so if your dog does not get to the expected size, you can pinpoint the cause and know how to deal with it. Some of the factors that affect a Chihuahua’s growth rate are:
Bloodline And Genes
The genes and bloodline of your Chihuahua play an important role in the dog’s growth and development. If a Chihuahua has large parents, it will be larger than the average Chihuahua. It is also possible for a Chihuahua to be small, despite having large parents. The dominant genes of the parents determine the size of the offspring.
Nutrition And Diet
The diet of your Chihuahua also affects its growth weight; feeding a dog a poor diet without the essential nutrients and vitamins will result in stunted growth and an unhealthy Chihuahua. For a Chihuahua to grow normally and be healthy, you must feed it a balanced diet regularly.
Hormones
The level of growth hormones in a Chihuahua will affect its growth. Growth hormones are responsible for dogs’ regular growth and development, so if a Chihuahua’s pituitary gland does not produce enough growth hormones, the dog will grow slowly and may not reach its full size.
Physical Activity
Regular exercise is important in a dog’s life, but too much exercise can affect a Chihuahua’s growth. Intense physical activity and exercise can fracture delicate structures like the growth plates or epiphyseal plates (an underdeveloped bone from which the pup’s leg bones grow).
How Much Do Chihuahuas Weigh?
Interestingly, a fully grown Chihuahua weighs less than some puppies of medium and large-sized dog breeds. A full-grown adult Chihuahua weighs about four to six pounds. A Chihuahua can add weight and weigh more than 6 pounds; if your Chihuahua weighs more than 8 pounds, you need to take it to a veterinary doctor.
The vet will diagnose the dog for any underlying health issues; if there is none, the dog will be placed on a diet to lose unnecessary weight and be fit. Also, an underweight Chihuahua is not healthy; in fact, they do not live as long as larger Chihuahuas.
Chihuahua Weight Chart
Professionals developed a weight chart for Chihuahuas to give an idea of how big a Chihuahua can get. The weight chart is only a guide; it is not ascertaining that the Chihuahua will be exactly the size.
Birth | 2.5 oz | 2.75 oz | 3 oz | 3.5 oz | 4 oz | 4.25 oz | 4.5 oz | 5 oz | 5.5 oz |
1 week | 3.75 | 4 | 5 | 5.5 | 6.5 | 7 | 8 | 9 | 9.5 |
2 weeks | 5 | 5.5 | 6.5 | 7 | 9 | 10 | 11 | 12.5 | 13.5 |
3 weeks | 6 | 7 | 8 | 9 | 11 | 13 | 14 | 16 | 17.5 |
4 weeks | 7 | 8 | 9.5 | 11 | 13 | 15 | 17 | 19 | 21 |
5 weeks | 8 | 9 | 11 | 13 | 15 | 17 | 19.5 | 22 | 24 |
6 weeks | 9 | 11 | 12.5 | 15 | 17.5 | 20 | 22 | 24 | 27 |
7 weeks | 10 | 12 | 14.5 | 17 | 19.5 | 22 | 24.5 | 27 | 30 |
8 weeks | 11 | 13 | 16 | 19 | 21.5 | 24 | 27 | 29 | 33 |
9 weeks | 12 | 15 | 17.5 | 20 | 23 | 26 | 29 | 32 | 35 |
10 weeks | 13 | 16 | 19 | 22 | 25 | 28 | 31 | 34 | 38 |
11 weeks | 14 | 17 | 21 | 24 | 27 | 31 | 34 | 37 | 42 |
12 weeks | 15 | 19 | 22 | 26 | 30 | 33 | 37 | 41 | 45 |
13 weeks | 16 | 20 | 24 | 28 | 32 | 36 | 40 | 44 | 49 |
14 weeks | 17 | 22 | 26 | 30 | 34 | 39 | 43 | 47 | 52 |
15 weeks | 19 | 23 | 28 | 32 | 37 | 41 | 46 | 51 | 56 |
16 weeks | 20 | 25 | 30 | 34 | 39 | 44 | 49 | 54 | 59 |
17 weeks | 21 | 26 | 31 | 36 | 41 | 46 | 51 | 57 | 62 |
18 weeks | 22 | 28 | 33 | 37 | 43 | 48 | 54 | 60 | 65 |
19 weeks | 23 | 29 | 34 | 39 | 44 | 50 | 56 | 62 | 67 |
20 weeks | 24 | 30 | 35 | 41 | 46 | 52 | 58 | 64 | 70 |
21 weeks | 25 | 31 | 36 | 42 | 48 | 54 | 60 | 66 | 72 |
22 weeks | 25 | 32 | 37 | 43 | 49 | 56 | 62 | 68 | 74 |
23 weeks | 26 | 33 | 38 | 44 | 50 | 57 | 64 | 70 | 76 |
24 weeks | 26 | 33 | 39 | 45 | 51 | 58 | 65 | 71 | 78 |
25 weeks | 27 | 34 | 40 | 46 | 52 | 59 | 66 | 72 | 79 |
26 weeks | 27 | 34 | 40 | 47 | 53 | 60 | 67 | 73 | 80 |
Final Adult Weight | 2 lb. | 2.5 lb. | 3 lb. | 3.5 lb. | 4 lb. | 4.5 lb. | 5 lb. | 5.5 lb. | 6 lb. |
Chihuahua Growth And Development
While monitoring your Chihuahua’s weight is important, you also need to ensure the dog is developing perfectly. To know when your Chihuahua is developing well, you need to know the growth rate at each point in time.
Keep reading: How Much Do Teacup Chihuahuas Cost?
0 To 2 Weeks Old
This is when the Chihuahua is born, and it weighs a few ounces. Within the first two weeks of its birth, it will experience rapid growth and double in size within days.
3 To 15 Weeks Old
The growth might seem less obvious and sporadic during this period, but the dog will gain weight consistently. This is when the puppy should be vaccinated.
4 To 9 Months Old
This is when the dog will reach its full adult size; Chihuahuas stop growing longer or taller within this age; it gains weight only.
10 To 18 Months Old
Sometimes, there is a delay in the development of some Chihuahuas; during this period, they mature into their full size if they did not earlier. At this age, they display adult behaviors.
Adulthood
At this stage, the most noticeable development is that the Chihuahua’s chest widens a little. There is no additional growth or weight gain.
Final Thoughts
Chihuahuas are so little that it is very easy for them to gain weight; this is prone to happen if you feed the dog treats every time. Also, if you do not allow the dog to exercise and play, it will add weight. Now that you know the normal weight of Chihuahuas and what to expect as they develop, you can care for your dog properly.
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Shawn Manaher is a serial entrepreneur but when he isn’t working, he loves dogs. He’s owned different pets over the years, and always gives a part of his heart to each pet.