Kitten Development Stages: Understanding Kitten Growth Milestones Week by Week
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The first eight weeks of a kitten’s life are full of rapid growth and major developmental changes. Each week, kittens will have different needs in terms of feeding, bathroom help, medical support, and warmth.
Understanding kitten growth stages can help you know what type of care they need, week by week, and whether your new kitten is developing normally.
Here’s what you need to know about each kitten development stage during their first eight weeks of life.
Key Takeaways
- Kittens develop quickly during the first eight weeks of life, progressing from being fully dependent on their mothers to walking, eating, and going to the bathroom on their own.
- During early kitten development (3–12 weeks of age), proper socialization is important to develop long-term confident and friendly behavior.
- Kittens should be dewormed at the vet at 2 weeks old, repeating every two weeks until broad-spectrum parasite control can begin.
- Kittens should begin veterinary wellness care around 6–8 weeks old.
- Seek veterinary care if a kitten is weak, not eating, losing weight, or having trouble breathing.
| Kitten Age | Kitten Development |
|---|---|
| Newborn | Weight: 1.8–5.3 ounces (50–150 grams) Feeding: Mother’s milk or a formula substitute every two hours Environment temperature: 85–90 F Physical characteristics: Eyes closed, ears folded, umbilical cord attached, toothless |
| 1 week old | Weight: 5.3–8.8 ounces (150–250 grams) Feeding: Mother’s milk or a formula substitute every two to three hours Environment temperature: 85 F Physical characteristics: Eyes closed, ears folded, toothless, can hold their head up |
| 2 weeks old | Weight: 8.8–12.3 ounces (250–350 grams) Feeding: Mother’s milk or a formula substitute every three to four hours Environment temperature: 80 F Physical characteristics: Eyes open and blue, ears small and rounded, toothless, taking wobbly first steps |
| 3 weeks old | Weight: 12.3–15.9 ounces (350–450 grams) Feeding: Mother’s milk or a formula substitute every four to five hours Environment temperature: 80 F Physical characteristics: Blue eyes, small ears pointing up, incisor teeth growing in |
| 4 weeks old | Weight: 15.9 ounces–1.2 pounds (450–550 grams) Feeding: Mother’s milk or a formula substitute every five hours Environment temperature: 70–75 F Physical characteristics: Canine teeth emerging, claws become retractable, beginning to use the litter box and play with toys |
| 5 weeks old | Weight: 1.2–1.4 pounds (550–650 grams) Feeding: Introduce wet kitten food along with milk Environment temperature: 70–75 F Physical characteristics: Premolar teeth emerging, running and playing confidently |
| 6 weeks old | Weight: 1.4–1.7 pounds (650–750 grams) Feeding: Weaned to wet food Environment temperature: 70–75 F Physical characteristics: Vision and hearing fully developed, molars growing in |
| 7 weeks old | Weight: 1.7–1.9 pounds (750–850 grams) Feeding: Eating wet food, can introduce dry food Environment temperature: 70–75 F Physical characteristics: All baby teeth grown in, eye color changing from blue, male kittens’ testicles may begin descending |
| 8 weeks old | Weight: 1.9–2.1 pounds (850–950 grams) Feeding: Eating wet and dry food Environment temperature: 70–75 F Physical characteristics: Eyes transitioned to the adult color, energetic and coordinated, able to be neutered and spayed |
Newborn Kitten Stage: Birth to Week 1
Average weight: 1.8–5.3 ounces (50–150 grams)
Physical Development
Newborn kittens will have their eyes closed and their ears folded. They will have no teeth and their gums, nose, and paws may appear bright pink in color. They do not yet have a gag reflex or the ability to thermoregulate.
The umbilical cord will be attached and will fall off on its own around 4 to 5 days of age. Their claws will be nonretractable.
At this age, they cannot hear or see; they can only navigate the world around them through scent and through seeking warmth and comfort.
Behavioral Development
Newborns will sleep for the majority of the day. Newborn kittens cannot defend themselves or walk, but they may be able to move around by crawling. A healthy newborn will wiggle and meow if handled.
Average Environmental Temperature
It is critical to provide a gentle heat source, like a heating pad, to keep the kitten warm and stable. The kitten's environment should be kept between 85–90 F at this time.
Care
Newborn kittens belong with their mother full-time. The mother will provide them with food, cleaning, warmth, and bathroom support.
If no mother is present, kittens must be bottle fed with kitten milk replacer every two hours by a knowledgeable caregiver, stimulated to go to the bathroom, and kept at an appropriate temperature.
1-Week-Old Kittens
Average weight: 5.3–8.8 ounces (150–250 grams). By 1 week of age, the kitten should have roughly doubled their birth weight.
Physical Development
One-week-old kittens will still have their eyes closed, but no umbilical cord. They will still have no teeth, and their claws will still be nonretractable. At around 7 days old, the ear canals will slowly begin to open and the ears will slightly unfold.
At 8–12 days old, the eyes will slowly begin to open, which can occur over the course of several days. One eye may open more quickly than the other; it’s important to let the kitten’s eyes open at their own pace. All kittens will be born with blue eyes, which will transition to an adult eye color with age.
Behavioral Development
One-week-old kittens, though larger than newborns, will still be mostly uncoordinated and will similarly sleep for the majority of the day. At this age, they should be able to hold their head up, move by wiggling their limbs, and be active and vocal if handled.
Average Environmental Temperature
It is critical to provide a gentle heat source to keep kittens at this age warm and stable. The kitten's environment should be kept around 85 F at this time.
Care
One-week-old kittens belong with their mother full-time. If no mother is present, they must be fed with a bottle and kitten formula every two to three hours by a knowledgeable caregiver, stimulated to go to the bathroom, and kept an appropriate temperature.
2-Week-Old Kittens
Average weight: 8.8–12.3 ounces (250–350 grams)
Physical Development
At 2 weeks of age, kittens' eyes will be fully open and baby blue. Their vision will be poor, and they will not be able to see long distances. The ear canals will be open, and the ears will be small and rounded, like a bear cub.
If you open the kitten’s mouth, you will find that there are still no teeth. Their claws will still be nonretractable.
Behavioral Development
Two-week-old kittens are becoming more coordinated and will be beginning to attempt their first steps. But they will be wobbly on their feet and uncoordinated.
Kittens at this age may exhibit some curiosity about the world around them, will not yet be playing, and will spend the majority of their time sleeping.
Average Environmental Temperature
It is critical to provide a gentle heat source to keep kittens at this age warm and stable. The kitten's environment should be kept around 80 F at this time.
Care
Two-week-old kittens belong with their mother full-time. If no mother is present, they must be fed with a bottle and kitten formula every three to four hours by a knowledgeable caregiver, stimulated to go to the bathroom, and kept an appropriate temperature. Two-week-old kittens should begin a dewormer from the veterinarian.
Introducing tiny kittens to brief, gentle handling by humans and for them to hear a calm, soft voice is an important way to start a foundation that humans are friendly.
3-Week-Old Kittens
Average weight: 12.3–15.9 ounces (350–450 grams)
Physical Development
At 3 weeks of age, kittens will have blue eyes and small ears that are beginning to point upward, like a miniature cat. The kitten’s vision and hearing will be slowly improving.
At this age, a kitten's first baby teeth will begin to emerge. The tiny teeth at the front of the mouth, called the incisors, will start to come through the gums. Kittens will slowly begin retracting their claws.
Behavioral Development
At this age, kittens will be walking and exploring their surroundings, including the litter box. They may begin to become curious about cat toys, though they are not yet able to run or chase after moving objects.
They will sleep frequently and may begin some small self-grooming behaviors. During this week, their coordination will be improving rapidly.
Average Environmental Temperature
Three-week-old kittens still require a heat source but will be more active and may stray from it when not sleeping. The kitten's environment should be around 80 F at this time.
Care
Three-week-old kittens belong with their mother full-time. If no mother is present, they must be fed with a bottle and kitten formula every four to five hours by a knowledgeable caregiver.
This age marks the beginning of the socialization period for kittens. Socialization is the process of helping kittens feel safe and comfortable around people, other animals, new environments, sounds, and everyday experiences.
Start by handling kittens gently. Shy kittens should be held for about 30 seconds at a time but then put down before they start squirming. If this process is repeated, shy kittens will learn to trust humans.
4-Week-Old Kittens
Average weight: 15.9 ounces–1.2 pounds (450–550 grams)
Physical Development
At 4 weeks of age, kittens will have much improved vision and hearing. The kitten's teeth will continue to develop; the long teeth next to the incisors, called the canine teeth, will start to come through the gums. Their claws will be retractable.
Behavioral Development
Four-week-old kittens will be confidently exploring and developing more coordination that allows them to walk, run, and even begin to play. With their improved senses, they will be notably more responsive, making frequent eye contact with caregivers and reacting to sights and sounds in the environment.
Their grooming skills may still be limited but improving.
This age marks a transition from needing to be stimulated by their mothers to go to the bathroom to being able to eliminate on their own. Where previously they may have only explored the litter box, now they’ll begin using it.
Average Environmental Temperature
Continue providing a heat source for 4-week-old kittens, although they will likely use it only when resting. The kitten's environment should stay comfortably warm and never colder than 70–75 F.
Care
Four-week-old kittens belong with their mother full-time. Orphans of this age should be bottle fed every five hours, including overnight.
Four-week-old kittens will generally be using the litter box. Most kittens will instinctually seek out the litter box to do their business, but some may need litter training.
Introduce a shallow cat litter box with a non-clumping, unscented cat litter, like Tidy Cats Breeze Unscented Cat Litter Pellets. (These pellets are designed to be used with the Breeze litter box system, but the box may be too high for your young kitten. It’s best to start with a low-entry litter box). Monitor them to make sure they don’t try to eat the litter.
As part of the socialization process, kittens should continue to receive positive interactions, so they learn to associate humans with kindness, safety, and affection. It’s also very important to gradually expose kittens to healthy cats, dogs, and children to help them become confident and well-adjusted companions.
At this age kittens typically progress from being curious about toys to beginning to play with toys. Now is a good time to start engaging them in playtime.
5-Week-Old Kittens
Average weight: 1.2–1.4 pounds (550–650 grams)
Physical Development
At 5 weeks of age, a kitten's baby teeth will continue to develop and the premolars will start to emerge. Their eyes will be blue, ears will be growing and pointed, and claws will be retractable.
Behavioral Development
Five-week-old kittens will be running and playing confidently. They will be developing social skills with humans and other animals. Their grooming skills will be improving. They will have perfected their use of the litter box by this age.
Average Environmental Temperature
A heating source is no longer required as long as the environment is a comfortable temperature of 70–75 F.
Care
Five-week-old kittens, if healthy, may begin the weaning process. Kittens should receive ample “slurry” or wet kitten food, in addition to access to their mother’s milk or, if orphaned, a bottle.
If weaned, food and water should be provided at all times. Always provide supplemental feeding and ensure that the kitten is maintaining a healthy weight and body condition during weaning. Provide a shallow litter box at all times.
6-Week-Old Kittens
Average weight: 1.4–1.7 pounds (650–750 grams)
Physical Development
At 6 weeks of age, a kitten's baby teeth will begin to reach their final stage of early development. The molars will start to emerge. The eyes will still be blue, and vision and hearing will be fully developed.
Behavioral Development
Six-week-old kittens will be socializing confidently with peers, play-fighting, pouncing, and defending themselves. They will be curious about their surroundings and eager to explore. They will be perfecting their grooming skills. Six-week-old kittens are becoming coordinated enough to jump off short furniture and land on their feet.
Average Environmental Temperature
At this age, a heating source is no longer required as long as the environment is a comfortable temperature of 70–75 F.
Care
Kittens at this age should be receiving ample kitten wet food, though they might not be completely weaned yet. Provide access to water, food, and a shallow litter box at all times.
At 6 weeks old, kittens need their first veterinary examination and can receive their first FVRCP vaccine to protect them against viruses (rhinotracheitis, calicivirus, and panleukopenia). Kittens need to be dewormed every two weeks until they can begin regular broad-spectrum parasite control, such as Revolution Plus, which is a topical solution formulated for kittens at least 8 weeks old who weigh a minimum of 2.8 pounds.
As part of their socialization, kittens need continued contact with children and people of all ages and types, as well as different animals.
7-Week-Old Kittens
Average weight: 1.7–1.9 pounds (750–850 grams)
Physical Development
All baby teeth will be present at 7 weeks of age. The kitten’s eye color will be changing, and the adult eye color will begin to emerge. Male kittens’ testicles may begin to descend around 7 weeks.
Behavioral Development
Seven-week-old kittens will experience a spike in energy. Sleep will decrease and time spent playing will increase. At this age, kittens are able to run, climb cat trees (but avoid very tall cat trees for your kitten’s safety), and confidently jump off of furniture.
Average Environmental Temperature
At this age, a heating source is no longer required as long as the environment is a comfortable temperature of 70–75 F.
Care
Kittens are usually fully weaned by this age. They should receive ample kitten wet food, and may have dry kitten food as a supplement. Provide access to water, food, and a shallow litter box at all times.
It is very important to continue to socialize your kitten by exposing them to diverse, positive experiences to develop their confidence.
8-Week-Old Kittens
Average weight: 1.9–2.1 pounds (850–950 grams)
Physical Development
All baby teeth will be present at 8 weeks of age. The eyes will be completely transitioned to their adult color of green, yellow, brown, or blue. The ears will be proportionate.
Behavioral Development
Eight-week-old kittens will be energetic and independent. Their agility and coordination will be nearly fully developed.
Average Environmental Temperature
A heating source is no longer required as long as the environment is a comfortable temperature of 70–75 F.
Care
Kittens should receive access to canned and dry kitten food three to four times per day, and they can receive the bulk of their calories from dry food if they choose. Provide access to water at all times.
At 8 weeks of age, you can switch to a clumping litter, like Dr. Elsey’s Kitten Attract.
If two weeks have passed since their first FVRCP vaccine, kittens may receive a booster at this time, as well as deworming. It is also a good idea to have a fecal test run to check for internal parasites. Fecal tests should be run at least four times during the first year of life.
At this age, if they are 2 pounds and healthy, they may be spayed or neutered, microchipped, and adopted.
To protect your kitten from harmful parasites like heartworms, fleas, intestinal worms like hookworms and roundworms, and ear mites, it is important to start your kitten on a prescription-strength medication once a month and continue this consistently year-round.
Revolution Topical Solution for Puppies & Kittens provides protection against fleas, ear mites, heartworms, hookworms, and roundworms for kittens at least 8 weeks of age who are under 5 pounds.
For broad-spectrum coverage, Revolution Plus Topical Solution for Cats provides 7-in-1 protection against fleas, ticks, ear mites, heartworm disease, hookworms, roundworms, and tapeworms* for kittens at least 8 weeks of age and weighingat least 2.8 pounds.
Continue safe and positive interactions with humans and other animals so they can develop calm and balanced behavior when exposed to new experiences.
Kitten Development Stages FAQs
When do kittens open their eyes?
Most kittens begin opening their eyes between 8–12 days old. Vision will be poor at first, but will be much improved by the four-week mark.
When do kittens start walking?
Kittens typically begin wobbling and attempting to walk around 2–3 weeks old.
When do kittens start eating solid food?
Most kittens begin weaning and trying solid food like canned kitten food and be introduced to small amounts of dry kitten food around 5 weeks old. Most kittens are fully weaned by around 7 weeks old.
When can kittens start flea and tick prevention?
Kittens can start flea and tick prevention at 8 weeks of age. Revolution Topical Solution for Puppies & Kittens provides flea prevention as well as protection against heartworms, hookworms, roundworms, and ear mites for kittens at least 8 weeks old and weighing less than 5 pounds.
If your kitten is at least 8 weeks of age and weighs at least 2.8 pounds, Revolution Topical Solution for Cats provides 7-in-1 protection against fleas and ticks, heartworms, hookworms, roundworms, tapeworms*, and ear mites.
When is a cat fully grown?
Cats are typically considered fully grown at about 1 year of age, when they have reached their mature size, which averages 8–10 pounds.
At this stage, they will still have a lot of energy and kitten behaviors, such as climbing furniture and chasing feet, but physically they are mature adults.
DISCLAIMER
*Prevents flea tapeworm (Dipylidium caninum) by killing fleas.
