How Long Is a Cat a Kitten?

He's a little furry ball now, but he'll be an adult soon.
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Those huge eyes and that big head say “kitten.” When you look at the short limbs and the little body, you might experience “kitty cuteness overload,” but let’s back up just a bit. Knowing when your kitten is a full-grown cat affects how you handle him.

Age Range for a Kitten

Your kitten grows fast. He’ll reach adolescence much sooner than a human child. From birth to about 6 months of age, your feline is officially a kitten; then, as he enters puberty, he leaves kittenhood behind. From here until his 6th birthday, he’s considered a young adult.

Hold on, cat parent, because the ride becomes wild now. If you don’t plan to neuter him, expect him to display all the signs of sexual maturity. If you do get him neutered, he’ll still become an adult cat but won’t enter sexual maturity. Neutering your male kitten before he reaches 6 months of age means you may not need to deal with any of his sexual acting out. If he still mounts a female cat it’s because his brain is hard-wired and he enjoys doing so. Relax. He can’t get her pregnant because his testes have been removed.

Sexual Maturity

Your male kitten-becoming-a-cat reaches sexual maturity some time between 9 and 12 months of age. A few signs that he has reached this stage of his life can include his growing interest in developing impeccable escape skills. When you enter your front door, he might try to slip out between your feet. Another sign of sexual maturity is urine spraying. Typically, he’ll back up to a wall, raise his butt and tail, then spray smelly urine on your wall. Oh, phew, the smell. He’s marking his territory. He’ll also develop flesh pads on his cheeks to protect him in fights. If he does get out of your home, he could become involved in fights with other male cats.

That First Year

Once your kitten has entered puberty -- becoming, in essence, a teenager -- his growth and development becomes less obvious, especially if you have him neutered. His physical growth continues, although it slows down. Expect him to become more confident in his skills, as well as more likely to defy you, his parent. His body is still developing on the inside as he finally matures into a full-grown cat. You might be surprised to see him continuing to grow into his full adult size after he passes his first birthday.

Cat Lifespan

Your cat’s expected lifespan depends on whether you allow him to roam around outdoors. If so, expect him to live for about 3 to 5 years. If he’s solely an indoors cat, he can live on average 16 years, although he might live on for a few years beyond that. To extend his life as much as possible, take him for regular veterinary exams and make sure he gets his vaccinations every year. Feed him the healthiest cat food you can and help him maintain a healthy weight. Give him plenty of chances for exercise with toys that encourage him to play with you, jump around and work off that energy.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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