Predicted Adult Size
3.5 kg - 4.9 kg
Estimated at 12 months · Confidence: high
Based on current curve position plus domestic shorthair growth expectations.
Free Tool · Newborns to 12 Months · Adult Size Prediction
Kitten Growth Calculator: Is Your Kitten Growing Normally?
Every gram counts when you are raising a kitten. Enter age and weight to see where they fall on the growth curve, predict adult size, and get a milestone timeline from newborn to first birthday.
Based on Waltham-style growth referencesSupports newborns to 12 monthsBreed-adjusted predictions for 16 breeds
Calculate Your Kitten's Growth
Updated just now
Mochi's Growth Report
Growth Status
Growing Normally
- Current
- 850g at 8.0 weeks
- Expected range
- 720g-980g
- Percentile
- ~50th
Your kitten is right on track and growing at a healthy, steady pace.
Next Milestone
Second FVRCP vaccination
In approximately 1 week(s), at 9 weeks.
Ask your vet whether FeLV vaccination fits your kitten's lifestyle risk.
Care priorities now
- Vaccines: complete FVRCP series and rabies around 12 weeks.
- Spay/neuter: discuss scheduling for 4-5 months.
- Dental: begin tooth brushing habits.
Growth Chart
Mochi's Growth Curve
Compare actual weight against the standard P10-P90 range, median growth curve, and breed-adjusted expected line.
Normal range Expected Mochi's weight
Development Timeline
Kitten Development Milestones
From birth to adulthood, these are the key health, behavior, nutrition, and social milestones in a kitten's first year.
Neonatal Stage (0-2 weeks)
Completely dependent - eyes and ears sealed
Neonatal Stage (0-2 weeks)
Completely dependent - eyes and ears sealed
Day 0
Birth
Eyes and ears sealed. Completely dependent on mother and unable to regulate body temperature.
Keep the nest warm. Kittens must nurse within 24 hours for colostrum.
Weight: 85-115g1 weeks
Umbilical cord falls off
The umbilical cord dries and detaches. Many kittens double their birth weight by the end of week one.
Weigh daily. Any kitten not gaining 10-15g per day needs support.
Weight: 150-200g2 weeks
Eyes begin to open
Eyes start opening and ears begin to unfold. Newborn-blue eyes are normal at this stage.
Never force eyes open. Keep light levels gentle.
Weight: 230-310g- Temperature: keep nest warm at 29-32°C (85-90°F).
- Feeding: every 2 hours if orphaned, including overnight.
- Weighing: daily, with 10-15g/day gain expected.
- Vet: urgent attention if not nursing or losing weight.
Transitional Stage (2-4 weeks)
Eyes open, ears unfold, first steps
Transitional Stage (2-4 weeks)
Eyes open, ears unfold, first steps
2 weeks
Eyes begin to open
Eyes start opening and ears begin to unfold. Newborn-blue eyes are normal at this stage.
Never force eyes open. Keep light levels gentle.
Weight: 230-310g3 weeks
Ears fully open
Hearing becomes functional and the first wobbly steps begin.
Start brief gentle handling sessions to support socialization.
Weight: 310-420g3 weeks
Baby teeth begin erupting
Deciduous teeth start coming in, usually incisors first and canines soon after.
Introduce tiny amounts of wet kitten food mixed with kitten milk replacer.
Weight: 310-420g4 weeks
Weaning begins
Kittens can begin transitioning toward solid food while milk remains important.
Offer wet kitten food mixed with warm water or KMR to a gruel consistency.
Weight: 390-530g4 weeks
Critical socialization window opens
The most important social period begins. Gentle experiences now shape adult confidence.
Expose kittens to safe handling, household sounds, and supervised new environments.
Weight: 390-530g- Eyes: open gradually; keep the environment dim.
- Teeth: baby teeth begin erupting.
- Food: introduce wet food gruel at 3-4 weeks.
- Litter: introduce a low-sided litter box at 3 weeks.
Socialization Stage (4-8 weeks)
The most critical window for personality development
Socialization Stage (4-8 weeks)
The most critical window for personality development
This is the single most important social window in your kitten's first year. Positive experiences with people, sounds, and safe environments during weeks 4-8 shape confidence for life.
4 weeks
Weaning begins
Kittens can begin transitioning toward solid food while milk remains important.
Offer wet kitten food mixed with warm water or KMR to a gruel consistency.
Weight: 390-530g4 weeks
Critical socialization window opens
The most important social period begins. Gentle experiences now shape adult confidence.
Expose kittens to safe handling, household sounds, and supervised new environments.
Weight: 390-530g5 weeks
Play behavior begins
Object play and early prey behaviors emerge as kittens interact with littermates.
Use safe toys. Avoid hands and feet as toys.
Weight: 470-640g6 weeks
First vaccination window
Maternal antibodies begin declining and the first FVRCP vaccination can be given.
Schedule the first vet visit and discuss parasite prevention.
Weight: 550-750g7 weeks
Litter box training complete
Most kittens reliably use a low-sided litter box independently.
Use unscented, non-clumping litter for kittens under 3 months.
Weight: 630-860g8 weeks
Ready for adoption
Kittens are usually weaned, socialized, and old enough for adoption.
Eight weeks is the minimum. Ten to twelve weeks is better for many kittens.
Weight: 720-980g- Socialization: handle daily and introduce different people.
- Sounds: expose gently to TV, doorbells, and household noise.
- Vaccines: first FVRCP can begin at 6 weeks.
- Environment: support safe exploration of new spaces.
Juvenile Stage (8 weeks-6 months)
Rapid growth, high energy, vaccine series
You are here
Juvenile Stage (8 weeks-6 months)
Rapid growth, high energy, vaccine series
8 weeks
Ready for adoption
Kittens are usually weaned, socialized, and old enough for adoption.
Eight weeks is the minimum. Ten to twelve weeks is better for many kittens.
Weight: 720-980g9 weeks
Second FVRCP vaccination
A booster is commonly given three to four weeks after the first dose.
Ask your vet whether FeLV vaccination fits your kitten's lifestyle risk.
Weight: 810-1110g12 weeks
Third FVRCP + Rabies vaccination
The kitten series continues and rabies vaccination is due in many regions.
Discuss flea, tick, heartworm prevention, and dental habits.
Weight: 1.1-1.5 kg16 weeks
Critical socialization window closes
The sensitive socialization period ends and new experiences may become harder to accept.
Keep enrichment going, but expect slower adjustment to unfamiliar situations.
Weight: 1.4-2.0 kg20 weeks
Spay/neuter recommended window
Five months is a common target window, ideally before the first heat in females.
Discuss timing with your veterinarian.
Weight: 1.8-2.5 kg24 weeks
Transition to adult food begins
At around six months, some kittens can begin a gradual adult-food transition.
Change food over 7-10 days and monitor stool and appetite.
Weight: 2.2-3.0 kg- Vaccines: complete FVRCP series and rabies around 12 weeks.
- Spay/neuter: discuss scheduling for 4-5 months.
- Dental: begin tooth brushing habits.
- Play: use 2-3 interactive play sessions daily.
Adolescent Stage (6-12 months)
Approaching adult size, energy remains high
Adolescent Stage (6-12 months)
Approaching adult size, energy remains high
24 weeks
Transition to adult food begins
At around six months, some kittens can begin a gradual adult-food transition.
Change food over 7-10 days and monitor stool and appetite.
Weight: 2.2-3.0 kg32 weeks
Nearing adult size
Most domestic cats are around three quarters of their adult weight and growth slows.
Monitor monthly and adjust portions after spay or neuter.
Weight: 2.7-3.8 kg52 weeks
First birthday - adult cat
Most domestic cats reach adult size and shift into an adult care rhythm.
Switch fully to adult care and schedule an annual wellness exam.
Weight: 3.5-4.9 kg- Food: transition to adult food gradually after 6 months when appropriate.
- Weight: monitor monthly for post-spay weight gain.
- Vet: plan a one-year wellness exam.
- Growth: most domestic cats reach full size by 12 months.
Weight Reference
Kitten Growth Chart: Week-by-Week Weight Reference
Standard P10-P90 ranges for domestic mixed-breed kittens. Breed-adjusted values may differ.
| Age | Weight Range (Normal) | Daily Gain | Key Milestone |
|---|---|---|---|
| Birth | 85-115g | - | Eyes/ears sealed |
| 1 week | 150-200g | 10-15g/day | Must double birth weight |
| 2 weeks | 230-310g | 10-15g/day | Eyes begin opening |
| 3 weeks | 310-420g | 10-15g/day | Ears open, first steps |
| 4 weeks | 390-530g | 10-15g/day | Weaning begins |
| 6 weeks | 550-750g | 10-15g/day | First vaccination |
| 8 weeks ← Your Kitten | 720-980g | 10-15g/day | Ready for adoption |
| 10 weeks | 900-1,240g | 10-15g/day | Second vaccination |
| 12 weeks | 1.1-1.5 kg | 8-12g/day | Third vaccination + Rabies |
| 16 weeks | 1.4-2.0 kg | 8-10g/day | Socialization window closes |
| 20 weeks | 1.8-2.5 kg | 6-8g/day | Spay/Neuter recommended |
| 24 weeks | 2.2-3.0 kg | 5-7g/day | Transition to adult food |
| 32 weeks | 2.7-3.8 kg | 3-5g/day | ~75% of adult weight |
| 40 weeks | 3.1-4.4 kg | 2-3g/day | ~90% of adult weight |
| 52 weeks | 3.5-4.9 kg | Minimal | Full adult size (most breeds) |
Values represent P10-P90 range for domestic shorthair cats. Large breeds may weigh 50-80% more, while small breeds may weigh 20-30% less.
Adult Size
How to Predict Your Kitten's Adult Size
The 16-Week Rule
The simplest estimate is to weigh your kitten at 16 weeks and multiply by 2. A 1.8 kg kitten at 16 weeks is likely to land near 3.6 kg as an adult. This is most useful for mixed-breed kittens and less reliable for newborns, very large breeds, or unusual growth patterns.
Weight at 16 weeks x 2 ≈ Adult weight
Breed Impact
How Breed Affects Growth
Small Breeds
Singapura, Devon Rex
Adult weight: 2-4 kg · Mature at 10-12 months
Medium Breeds
Domestic Shorthair, Siamese
Adult weight: 3.5-5.5 kg · Standard curve
Large Breeds
Maine Coon, Ragdoll
Adult weight: 5.5-10 kg · Mature at 36-48 months
Newborn Care
Newborn Kitten Care: Weight Monitoring Guide
For orphaned kittens, foster carers, and new kitten parents.
Newborn kittens are fragile. A kitten that fails to gain weight for 24 hours, or loses any weight, needs veterinary attention immediately. Do not wait.
Daily Weighing Protocol
- Use a digital kitchen scale with 0.1g precision.
- Weigh at the same time each day, before feeding.
- Normal weeks 1-4: gaining 10-15g/day.
- Emergency: any weight loss or less than 5g/day for 2+ days.
KMR Feeding Guide
- 0-1 week: 2-4ml every 2 hours.
- 1-2 weeks: 5-7ml every 2 hours.
- 2-3 weeks: 7-10ml every 3 hours.
- 4-6 weeks: 13-17ml every 4 hours while weaning.
Temperature Requirements
- Week 1: 29-32°C environment temperature.
- Week 2: 27-29°C environment temperature.
- Week 3: 24-27°C environment temperature.
- Red flags: constant crying, refusing bottle, limp body, pale or blue gums.
Safety
When to Be Concerned About Kitten Growth
Seek Veterinary Care Immediately
- Kitten loses any weight.
- No gain for 24+ hours in neonates or 48+ hours in older kittens.
- Stops nursing, refuses bottle, or cries constantly.
- Pale, blue, or yellow gums; labored breathing; bloated abdomen.
- Diarrhea or vomiting in kittens under 4 weeks.
Monitor Closely, Consult Vet Soon
- Weight consistently below P10 for age.
- Gain slows significantly without explanation.
- Much smaller than littermates.
- Eyes not opening by 2 weeks.
- Sneezing, eye discharge, poor coat condition, or low playfulness.
About Fading Kitten Syndrome: this describes sudden rapid decline in young kittens, often linked to hypothermia, hypoglycemia, infection, congenital defects, or inadequate nutrition. Rapid deterioration needs emergency veterinary care.
Growth tracking
A single kitten weight means less than the growth trend
Kittens grow quickly, and a normal number depends heavily on age in weeks, breed, sex, and recent health. The calculator is designed to show whether a kitten is tracking near an expected curve and whether the next milestone fits the current age.
Result guide
How to read a kitten growth result
The percentile and status should be interpreted as a trend marker. A kitten near the same curve over time is usually less concerning than a kitten who drops across curves, stops gaining, or loses weight.
- Newborns should be weighed daily because small changes can become urgent quickly.
- After weaning, weekly weights are usually enough unless appetite or stool changes.
- Large breeds may stay on a heavier, slower-maturing track for much longer.
- Adult weight predictions are estimates and become more useful around 12-16 weeks.
Percentiles are not grades
A P10 kitten is not automatically unhealthy and a P90 kitten is not automatically overweight. The concern is whether the curve fits the kitten and remains stable.
The 16-week rule is only a shortcut
Doubling 16-week weight is useful as a quick estimate, but breed factor and current percentile make the calculator's adult-size range more realistic.
Milestones add context
Eyes, hearing, walking, weaning, social play, and adult teeth help confirm whether the weight result matches overall development.
Growth decisions
Separate normal variation from a growth problem
A kitten can be small and healthy, large and healthy, or exactly average but starting to fall behind. The key is whether weight, age, appetite, stool, warmth, and milestones tell the same story.
Stable percentile
A kitten tracking along the same curve is usually less concerning than a kitten crossing downward through curves, even if the stable percentile is not average.
Keep recording dated weights and compare the trend rather than chasing the median.
Below expected range
A low result needs context: litter size, orphan status, parasites, diarrhea, appetite, and breed size can all affect growth.
Increase monitoring frequency and review feeding, warmth, and stool quality.
Large-breed kitten
Large breeds can look ahead of a standard curve while still maturing slowly. Adult-size predictions should be treated as a range, not a promise.
Recalculate around 12-16 weeks when adult-size estimates become more informative.
Daily for neonates
Weigh newborn or fragile kittens daily and act quickly if gain stops.
Weekly after weaning
Weekly weights are usually practical once a kitten is eating reliably.
Milestone reviews
Recheck when weaning, vaccination, adoption, or rapid diet changes occur.
How to build a useful kitten record
1
Use consistent units
For young kittens, grams are usually clearer than pounds because small changes matter.
2
Record weight with date
A dated weight history lets you distinguish a naturally small kitten from one whose gain has slowed.
3
Pair numbers with observations
Add appetite, nursing, stool, warmth, and energy notes when a kitten is very young or medically fragile.
FAQ
Frequently Asked Questions About Kitten Growth
How much should a kitten weigh at 8 weeks?
A healthy 8-week-old kitten typically weighs between 720g and 980g, or about 0.7-1.0 kg. A practical benchmark is roughly 100g per week of age, but breed, sex, litter size, nutrition, and health all affect the result.
When do kittens stop growing?
Most domestic cats reach full adult size between 10 and 12 months. Large breeds such as Maine Coons and Ragdolls can keep growing for 3-4 years, so a one-year-old large-breed kitten may not be fully mature.
How much should a newborn kitten weigh?
Healthy newborn kittens commonly weigh 85-115g at birth and should gain about 10-15g per day in the first two weeks. Any weight loss, or failure to gain for 24 hours, needs veterinary attention.
How big will my kitten get?
Adult size depends mainly on breed and sex. Most domestic mixed-breed cats land around 3.5-5.5 kg. A quick estimate is to multiply the 16-week weight by 2, while this calculator uses the kitten's current percentile and breed factor.
Is my kitten underweight?
A kitten below the expected range for their age, especially below the P10 curve, should be monitored closely. Kittens below 80% of the expected weight, or any kitten losing weight, should be seen by a veterinarian.
How often should I weigh my kitten?
Newborn kittens should be weighed daily, especially if orphaned or hand-reared. Kittens 4-12 weeks can usually be weighed weekly, and kittens 3-6 months can be weighed every one to two weeks.
What if my kitten is not gaining weight?
For neonates, no gain for 24 hours is urgent. Older kittens that fail to gain for 48 hours, stop eating, become cold, vomit, or develop diarrhea need prompt veterinary care.
Can breed change the kitten weight chart?
Yes. Large breeds may weigh much more and mature much later than the standard domestic shorthair curve. Small breeds may plateau earlier and stay substantially lighter.
Related Tools
Pair growth tracking with daily care planning
Cat Age Calculator
Convert cat years to human years using the feline-specific aging curve, not the outdated multiply-by-7 dog formula.
Cat Food Calculator
Calculate daily portions in grams and cups for dry, wet, or mixed diets adjusted for age, weight, and activity.
Cat Weight Calculator
Compare your cat's weight against breed-specific healthy ranges and get a Body Condition Score interpretation.