Your cat hits similar developmental milestones to a human baby in its lifespan.
However, unlike a human child, there is no definitive age where you’ll know for sure that your cat has stopped growing and maturing.
While it is true that cats can continue to grow after the first year, their growth rate will slow down significantly.
The best way to understand when your cat has stopped growing is to measure and weigh your cat once a month.
Cats continue to gain height (determined from the ground to the top of their shoulders) as well as length.
If you measure your kitty once a month, you’ll be able to note when those measurements stop changing.
A cat’s weight can also reveal its maturity level or approximate age. You can estimate your cat’s adult weight by weighing them at 16 weeks of age and doubling that number.
Be sure to note that this is merely an estimation and your cat’s weight may differ. Similar to measuring a cat’s height and weight, weighing a cat monthly can also aid in determining when he or she reaches its full size.