When Do Cats Stop Growing?

picture of a small cat

When you first brought home your little feline bundle of joy, you relished in his tiny size. Over time, that little kitten began to grow, and it seemed there was no end to his spurts of growth. With growth came a change in appetite to help foster your kitten’s health and development. But you’ve been watching your cat’s size increase for months now, and you can’t help but wonder, when do cats stop growing?

Much like their canine counterparts, cats grow at different rates which are largely dependent on their breeds. Some varieties of cats remain quite small throughout their lives, meaning they achieve adult height in a much more rapid fashion than other breeds who take longer to reach maturity.

Cat Life Stages

While cats are said to reach their adult height and weight as early as 8 months or as late as 16 months, the issue of full maturity is more complex than can be limited to a specific age. Unlike dogs, cats go through a number of development stages during which marked growth can be measured.

Veterinarians divide the feline life stages into the following categories:

Kitten (Birth to 6 months)

During this stage of life, your kitten will experience many different changes. This is the developmental period characterized by the most growth in your cat’s skin and bones. During this phase, it may seem as though your cat increases in size every single day. His growth may appear rapid and dramatic.

At 4 months of age, most cats begin puberty. His growth is further exacerbated by the advent of full sexual maturity. While development is still taking place during this phase, it is at a much less noticeable pace than during the first 3 months of the kitten stage.

  • Junior Life (7 to 24 months)
  • Prime Life (3 to 6 years)
  • Mature Life (7 to 10 years)
  • Senior Life (11 to 14 years)
  • Geriatric Life (15+ years)

Cats grow in three distinctly different areas. Over the course of the kitten stage and well into the junior life phase of life, your cat will grow in height, length, and weight until he reaches his full genetic potential. However, his breed will determine the amount of time it will take to achieve his adult size.

The issue becomes even more complicated when you consider mixed breed cats. Since a breeding of mixed parentage combines a vastly different set of genes and typically it is not known which breeds of cats comprise the pedigree of your mixed breed, it can be very difficult to determine just how big your cat will be when fully grown. Even more challenging is ascertaining when he will be finished growing! The best you can do is have a veterinarian assess what breeds might be in your cat’s pedigree then make an educated guess based on the coupling that produced your cat. It’s certainly not an exact science, but it is a good starting point and may prove to be quite accurate.

Appropriate Growth for Life Stages

As with all animals, growth that is too rapid is problematic. At the same time, growth that occurs too slowly can also be indicative of issues at play.

Here is a sample chart of what you can expect during each stage of your kitten’s development:

3 months
12 week old kittens should have tripled or quadrupled their original birth weight, leaving them weighing from 2 lbs on the small end to up to 4 lbs on the high end.

4 months
At 16 weeks, your kitten should have gained a little weight and should now top the scale around 4 to 5 lbs.

5 months
A 5 month old kitten’s size should have increased by a pound or so, meaning your kitten’s ideal weight for this age is 5-6 lbs.

6 months
At 6 months of age, your kitten’s weight should fall within the range of 6-8 lbs. At this age, your kitten is now ideally at ¾’s of her adult height as well as her fully grown length. What remains now is marginal growth and continued weight development as your kitten’s muscles strengthen and grow. After 1 year of age, weight gain should cease.

Though this chart provides a handy set of averages, some cats are far slower to develop and may require up to 18 months to reach full maturity. Larger cats often take longer still, not reaching their full adult dimensions until they are up to 5 years old.

Keeping an Eye

To help chart your kitten’s progress, it is important to establish benchmarks. Visiting your veterinarian shortly after acquiring your kitten is a great way to measure your cat’s growth cycle. Frequent wellness examinations will reveal growth patterns and can help ward off any potential issues relating to sluggish or overzealous growth.

It is also very important to keep an eye on your cat’s weight. Obesity in house cats has reached epidemic proportions and can lead to a host of health problems, many of which are life-threatening. Your veterinarian can assist you with formulating a correct diet for all life stages as well as monitor your cat’s weight to ensure he is as healthy and happy as can be. When it comes to weight gain, an ounce of prevention really is worth a pound of cure.

Obstacles to Growth

Proper nutrition is key to healthy development. Excess minerals and vitamins can lead to delays in growth and maturity. Ensuring your cat receives a diet that is properly balanced to meet the needs of a growing cat is critical. Diets that are too rich in calcium can also delay development.

During your cat’s growing phases, his nutritional requirements will also be higher. Growing cats require more food than cats who have already achieved full maturity. Be certain to have your veterinarian assist you in selecting an appropriate diet for your cat’s life stage then determine what amount your cat should be fed and how many times per day for optimum health and nutrition.

When do cats stop growing? Though there is no one set answer since cat genetics are largely dependent on breed, it is relatively safe to say that your cat will reach his full adult height, length, and weight as early as 8 months or as late as 18. Until then, stock up on a nutritionally balanced cat food that is appropriate for your cat’s life stage to help keep Frisky healthy and happy!



Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents