Updated: April 1st, 2020.
Have you ever wondered how old your cat is compared to human years? Cats age way faster than humans, even though they may still look young, they tend to age pretty quickly.
Depending on if your cat lives indoors or outdoors that significantly changes her lifespan.
There’s a common misconception that one cat year is equivalent to seven human years. That’s not correct. You can check a more appropriate comparison on the table below.
Important Note: You should also know that an outdoor cat ages way faster than cats that live indoors. The lifespan of cats that live outdoors is an average of only 2 to 6 years. They can live longer, but due to all the dangers they face, their lifespan becomes significantly reduced in comparison to cats that live indoors.
Lifestages of a Cat:
Development of a newborn kitten
The first eight weeks of a kitten’s life is full of changes and progress. Newborn kittens are blind, defenseless, and they are incredibly small.
When kittens reach the age of eight weeks, they’ll start to have more activity and start playing, running around, etc.
On each week of growth, kittens need assistance with different things such as medical support, warmth, and feeding.
It’s crucial to quickly identify their age to help them with their individual needs. The care a newborn kitten need is different than a cat that has been alive for 8+ weeks.
Physical Development: Newborn kittens have their eyes closed, and their ears are folded. They cannot see nor hear. Newborns navigate mainly through their scent glands, they also have whiskers that will stiffen up and get stronger with time. Their claws are not yet functional. Their gag reflex or ability to thermoregulate is inexistent.
Behavioral Development: They will spend the majority of the day sleeping. Since they cannot walk yet nor defend themselves, they crawl to move around. If the newborn kitten is healthy, she’ll be able to meow.
Average Temperature: A rule of thumb is 95 to 97 degrees Fahrenheit (35 to 36 Celcius). If you live in a cold city or town, it’s essential to provide warmth through a heat source to keep the nebown kitten safe and comfortable.
Average Weight: Their weight varies depending on the breed, but a rule of thumb would be around 1.8 and 5.3 oz (50-150 grams).
Care Information: We recommended to let the newborn kitten stay with her mother full-time during the first 5 to 6 weeks.
She’ll provide the kitten with cleaning, food, warmth, and bathroom help. If the mother is not present, they must be fed with a nursing bottle specially designed for kittens. It’s recommended to feed them every two hours by somebody with a little bit of experience.
Physical Development: They will still have their eyes closed, but the umbilical cord is gone. Teeth are still not present, and their claws are not retractable yet by this stage.
At the end of the first week, their ears will start to unfold slowly. Between 8 to 12 days, they’ll begin to open their eyes. It happens typically in the course of multiple days. Sometimes one eye starts opening before the other. It’s a gradual process, and you should not force it. Just let the kittens open their eyes on their own.
All kittens are born with blue-greyish eyes, which will evolve to their adult eye color over time.
Behavioral Development: At this stage, kittens are larger than newborns, but they still lack coordination and will similarly sleep during most part of the day. They should be able to keep their head up and be a little bit more active and vocal.
Average Temperature: The average temperature should be around 97 to 98 degrees Fahrenheit (approximately 36 Celcius) by this stage it is also vital to keep the heat source for the kitten to stay warm and comfortable, especially if you live in a cold area.
Average Weight: The average weight should be around 5.3 to 8.8 oz (150 to 250 grams).
Care information: The care procedures should be the same as the previous week. We always recommended to let the newborn kittens stay with their mother full-time during the first couple of weeks.
She’ll provide the kittens with grooming, food, warmth, and bathroom help. If the mother is not present, they must be fed with a nursing bottle specially designed for kittens every two to three hours.
Physical Development: Their eyes will be completely open. Their level of vision will be pretty poor, and they can barely see from a close. They have no teeth yet, and their claws are still non-retractable. The ear canal will be open at this stage, with tiny small round ears.
Behavioral Development: A two-week-old kitten will be more coordinated and will start trying to walk for the first time. Kittens at this age show curiosity about their surroundings, they’ll still not be able to play so they’ll be sleeping most of the time (what a life, right? Haha. Just like you and me on Mondays).
Average Temperature: It should be around 98 to 99 degrees Fahrenheit (approximately 37 Celcius). At this stage, it is still vital to provide a heat source. The environment should be kept at around 80 degrees Fahrenheit (26 Celcius).
Average Weight: 8.8 to 12.3 oz (250 to 350 grams)
Care information: The care practices are the same as the previous weeks, but during this stage, kittens should be treated for common parasites. This can be done by a vet, or you can do it yourself at home.
Physical Development: At this stage, the kitten’s ability to hear and see will start to improve. You can also notice their first teeth. Kittens will even begin to be able to retract their claws.
Behavioral Development: Kittens will be able to start walking, exploring their surroundings. They may also start playing with toys but without full mobility yet. They will even sleep most of the day, and you’ll be able to notice some self-grooming practices. During week 3, their movement and coordination will start improving very fast.
Average Temperature: It should be around 99 to 100 degrees Fahrenheit (about 37-38 Celcius). They still need to be provided with a heat source. The environment should be kept at approximately 75 degrees Fahrenheit (23-24 Celcius).
Average Weight: 12.3 to 15.9 oz (350 to 450 grams).
Care information: We still recommend to keep the kittens alongside their mother. If the mother is not present, as mentioned previously, they must be fed with a nursing bottle specially designed for kittens.
We recommend feeding them every two hours by somebody with a little bit of experience. By this time, you should introduce the kitten to a cat litter box. Preferably with no clumping litter.
Physical Development: At week 4, their ability to hear and see will have improved quite a bit. Their teeth continue to develop. Their canine teeth will start to appear (The long teeth next to the incisors). They will be able to retract their claws fully.
Behavioral Development: They will be confident enough to start exploring, walk, run, and even play with their toys. They will also be way more responsive due to their improved senses. Kittens of 4 weeks of age, will start using the litter box.
Average Weight: 15.9 oz to 1.2 pounds (450 to 550 grams).
Care information: We recommend to let the newborn kitten stay with her mother full-time during the first 5 to 6 weeks. If the mother is not present, they should be fed with a nursing bottle every five hours, during the night too.
Physical Development: Their teeth continue to develop, and their premolar teeth start to appear.
Behavioral Development: They will start by showing the first signs of social skills with other pets and humans. Their self-grooming will also be improving, and their litterbox usage will be perfected.
Average Temperature: It should range from 100 to 101 degrees Fahrenheit ( around 38 Celcius). At this stage, there’s no need to keep a heat source since they will be way more active. However, the environment should be kept at around 75 degrees Fahrenheit (23-24 Celcius).
Average Weight: It should be from 1.2 to 1.4 pounds (550 to 650 grams).
Care Information: At five week-years-old kittens may start eating different food other than the mother’s milk. We recommend starting giving them wet food made for kittens in addition to the mother’s milk or through a nursing bottle made for kittens.
Physical Development: Their teeth start to reach their last steps of early development. The molars will begin to appear, and their ability to hear and see will be completely developed.
Behavioral Development: Think young Simba. Kittens his age will start to play-fight with other kittens, defend themselves and sometimes attack your ankles too (Yup!). At this age, they can also begin to jump around, pounce on things, etc.
Average Temperature: It should be around 100 to 101 degrees Fahrenheit (about 38 Celcius). At this stage, there’s no need to keep a heat source since they will be way more active. However, the environment should be kept at around 75 degrees Fahrenheit (23-24 Celcius).
Average Weight: They should weigh 1.4 to 1.7 pounds (650 to 750 grams).
Care Information: You should feed them with wet kitten food if they’re already weaned. Provide access to running water, a litter box, and food 24/7.
Important Note: Kittens of six weeks of age, should get their first FVRCP vaccine to protect themselves against viruses and different health complications.
Physical Development: At week seven, all their kitten teeth will be developed. Their eye colors will start changing to evolve to their adult eye color. If the kitten is a male, his testicles will begin to appear around this time.
Behavioral Development: Say hi to high energy! They will start to sleep less (hello night owl). Their musculature will begin to improve so they’ll be able to climb trees and jump off of furniture with full confidence.
Average Temperature: It should be 100 to 101 degrees Fahrenheit ( around 38 Celcius). At this stage, there’s no need to keep a heat source since they will be way more active. However, the environment should be kept at around 75 degrees Fahrenheit (23-24 Celcius).
Average Weight: It should be 1.7 to 1.9 pounds (750 to 850 grams).
Care Information: They should receive wet food, and you can also start giving them a little bit of dry food made for kittens as a supplement. Provide access to running water, a litter box, and food 24/7.
Physical Development: Their eyes will have been developed to their full adult color. Their kitten teeth will also be fully developed.
Behavioral Development: Their body coordination and agility will be almost entirely developed. They are very energetic and start moving independently, full of grace and curiosity.
Average Temperature: It should be 100 to 101 degrees Fahrenheit (around 38 Celcius). When kittens are eight weeks old, there’s no need to keep a heat source. The environment should be kept at approximately 75 degrees Fahrenheit (23-24 Celcius).
Average Weight: They should weigh around 1.9 to 2.1 pounds (850 to 950 grams).
Care Information: At eight weeks of age, cats should have access to wet kitten food and also a little bit of dry kitten food three to four times per day. It’s essential to give them full access to running water and a litter box. The importance of proper hydration is often overlooked. At this stage would also be wise to visit the vet to have them check for internal parasites and general health. If they are healthy and weigh 2 pounds or more, that means they can be microchipped, spayed/neutered and adopted.
The 6 main stages of feline development
Kittenhood (First Steps)
This is the earliest stage of a little feline’s lifecycle. It lasts for approximately six months after birth.
At this stage is when a cat starts discovering the world and developing their first habits—good and bad—the time and dedication you put into teaching them proper behavior will reflect the overall attitude of the kitten when she grows up.
It’s important to start introducing them to children and other pets so they can develop their social skills.
We also recommend starting to get them used to grooming sessions such as claw clipping, brushing, and baths, as well as to the correct use of the litter box.
This is also the perfect age to help them feel comfortable traveling by car with a cat carrier; that way, your visits to the vet will not be a hard battle.
This stage ranges from 7 months to 2 years of age. This would be 12 to 24 years if we convert them from cat years to human years. It is vital to encourage good behavior during this period.
Show your cat good manners and reward her with treats. Never scream at her because you’ll accomplish the opposite.
At this stage, your cat will start to reach sexual maturity. You should get some interactive toys for your cat, so she doesn’t get too bored, their level of activity and play-time will be at an all-time high, and they need to satisfy their needs otherwise they might become bored and show destructive behavior.
Cats usually reach their prime at the age of 3 (28 years if we convert it to human years), and this stage lasts for about three years. If your cat is healthy, she’ll look amazing, full of energy and grace.
Their level of activity will also be high. It’s vital to feed them with high-quality food and help them maintain proper hydration, ideally with a cat water fountain.
You should also take them to the veterinarian for routine checkups to make sure everything is fine.
At this stage, you’ll notice some behavioral changes. When your cat reaches the age of 7 (44 years if we convert cat years to human years), she’ll start losing her drive to play and run around. She’ll become less active and sleep more.
Since they are less active, you should closely monitor her eating and litter box habits. Always consult with your vet for the most appropriate diet.
Between the ages of 11 and 14, cats reach their senior years (the equivalent of 60 to 72 years when converted from cat years to human years).
We recommend taking your little feline to the vet even more frequently to monitor her health and overall well-being. At this age, they become more prone to develop health issues.
Cats reach their geriatric years at the age of 15, that’s 76+ years when converted to human years. These are the last years of a cat’s life, to make sure your cat lives as long as possible, it’s crucial to make sure she’s comfortable.
Give her lots of love, attention, and affection.
Also, make sure to provide easy access to the litter box, food, and filtered water.
Our feline behavior specialist Elizabeth Ann, wrote a wonderful and in-depth article about the common changes that senior and geriatric cats face.
The lifespan of a cat varies depending on if the cat lives indoors or outdoors. As seen in this article, cats that live outdoors have a shorter lifespan due to the outside world dangers. Cats that live indoors tend to live much longer if proper care is given.
Cats are fascinating creatures and it's truly a privilege to witness their entire development, it's magical.
If you already have cats, reading this article will help you understand the proper procedures to take to make sure they live a long and enjoyable life. If you don't have a cat yet but you're on the fence of getting one, make sure you know how to prepare before getting a one.
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