Which Littermate to Pick: 90 g and 5 Checks

Judge a litter on 3 numbers and 1 five-minute test: birth weight of 90 g or more, a gain of 90 to 100 g a week, 3 activity tiers matched to your household, and 5 health checks you do with your own hands. The smallest kitten is usually the one people reach for first, and it is usually the wrong pick for a first-time adopter with a 9-to-5 job.

Start with the 90 g number

A healthy newborn kitten weighs 90 to 120 g on day 1 and should double that by day 7 to 10. From week 2 to week 5, the target is 90 to 100 g of gain per week, and by 8 weeks a well-grown kitten sits at 700 to 900 g. Those are the 3 points to ask for: birth weight, current weight, and the weekly gain. A foster home that weighs the litter every 2 days can hand you a chart; a home that does not is guessing.

Consistency matters more than any single reading. A kitten at 640 g at 8 weeks that has gained 85 to 95 g a week for 4 straight weeks is a safer bet than one at 720 g that dropped 60 g last week after a bout of diarrhea. Ask for the last 4 weights, not the last 1.

Match activity in 3 tiers

Spend 10 minutes on the floor with the whole litter and a wand toy, then score each kitten. Tier matters more than cuteness, because a high-drive kitten in a 35 square meter flat with 2 adults working 50 hours a week becomes a furniture shredder by month 8.

Activity tier	Pounces in 10 min	Recovery after play, min	Best-fit home	Daily play needed
Tier 1, low	5 to 15	Under 2	Quiet flat, senior adopter, 1 cat	20 to 30 min
Tier 2, medium	15 to 30	2 to 5	Most homes, 1 to 2 cats	30 to 45 min
Tier 3, high	30 to 50	5 to 10	House with garden room, 2 cats	60 to 90 min
Tier 3, over-aroused	Over 50	Over 10	Experienced adopter only	90 min plus

The last row is not a bonus tier. A kitten that bites hands 10 or more times in 10 minutes, cannot settle, and pants after 5 minutes of play is showing early arousal problems that need a behavior plan, not more toys. Tier 2 is the safe middle for 80% of adopters.

The 5 checks you do yourself

Do these with the kitten on a table, in daylight, before you sign anything. Ten minutes is enough, and any finding means a vet visit before pickup, not after.

Eyes: clear, no yellow or green discharge, third eyelid not visible, pupils equal in a dim room.
Ears: no dark coffee-ground wax, no odor, and the kitten does not shake its head 3 or more times in a minute.
Mouth and gums: pink, not pale or brick red, no ulcers on the tongue or the roof of the mouth.
Belly and coat: no fleas or flea dirt, no swelling at the umbilicus bigger than a pea, skin without 2 or more bald patches.
Rear and gait: clean anus, no prolapse, walks on 4 legs without a head tilt, no hopping on 1 hind leg.

Also ask 2 questions the hands cannot answer: has the litter been dewormed at 2, 4, 6 and 8 weeks, and has either parent tested negative for FeLV and FIV? A negative test on the kitten before 12 weeks is unreliable, so the parent status is the number that counts.

Why not the smallest one

The runt is often the most charming kitten in the box and the most expensive. Expect 2 to 3 extra vet visits in year 1, a first-year bill 30 to 50% above a littermate's, and a feeding schedule of 5 to 6 small meals a day for the first 4 weeks home. A kitten that was 20% under its littermates at 8 weeks also has less reserve for the 12-hour fasting that comes with any surgery or illness.

Take the runt only if you can answer yes to 3 things: 1 vet visit a month for the first 3 months, feeding 5 times a day for 4 weeks, and a household where someone is home at midday. Otherwise pick the middle-weight, middle-activity kitten and let someone with that schedule take the runt.

What a 7-week temperament test actually predicts

Handling tests at 7 weeks predict maybe 30% of adult temperament; the rest is genetics, the 2 to 7 week window, and how you run the first 90 days. Do not pay a premium for the kitten that sat calmly in the assessor's lap. Do visit 3 times if you can: once at 6 weeks, once at 8, once at 10, and watch whether the same kitten approaches you each time. A kitten that hides on all 3 visits and a kitten that greets you on all 3 are the 2 most reliable readings you will get.

What the choice costs in year 1

A kitten runs USD 900 to 1,400 in year 1 against USD 550 to 900 for an adult, mostly in vaccines, 3 to 4 dewormings, spay or neuter, and 2 extra visits. Insurance for a kitten starts lower, around USD 22 to 38 a month, but check the waiting period: 14 days for illness and 12 months for orthopedic conditions is typical. The cost calculator lets you price 1 kitten against the pair before you commit.

The cost calculator lets you price 1 kitten against the pair before you commit.

Red flags: walk away

Do not take a kitten home with any of these: labored breathing at rest, a distended hard belly with no stool in 24 hours, eyes stuck shut with pus, a temperature under 37.5 C or over 39.5 C, or a litter where 2 or more kittens died in the last 7 days. A breeder or foster who cannot produce a weight chart, refuses a home visit, or hands over a kitten at 6 weeks is telling you what the next 12 months will look like.

If you are set on a kitten but the litter looks weak, wait 2 weeks and look again, or take an adult: kitten or adult cat compares the 2 on time, cost and health risk with the same numbers. And if you are choosing at a foster home rather than a shelter, the foster-to-adopt route usually lets you see the weight chart before you decide.

Your 5-step plan

Ask for the last 4 weights and the birth weight before your first visit.
Score all the kittens on the activity table with 1 toy and 10 minutes.
Run the 5 checks on the 2 kittens you shortlist, in daylight, on a table.
Ask about deworming dates and the parents' FeLV and FIV status.
Book the pickup for 8 to 10 weeks, and the first vet visit within 72 hours.

The choice you will not regret is the one made on a weight chart and 10 minutes of floor time, not the one made in the first 30 seconds.

Terms mentioned in this article

FIV

Frequently asked

Should I pick the calm kitten or the playful one?

Match the kitten to your daily schedule, not to the moment. A tier 2 kitten, 15 to 30 pounces in 10 minutes, fits most homes with 30 to 45 minutes of play a day. Tier 3 needs 60 to 90 minutes and a second cat or a large flat.

Is the runt of the litter a bad choice?

Not bad, just expensive. Expect 2 to 3 extra vet visits in year 1, a bill 30 to 50% higher than a littermate's, and 5 to 6 small meals a day for the first 4 weeks. Take it only if you can manage monthly checkups for 3 months.

How old should a kitten be at pickup?

8 weeks is the legal minimum in most US states, and 10 to 12 weeks is better. Between 8 and 12 weeks the kitten gains about 90 to 100 g a week and finishes the socialization window with its littermates, which cuts later fear and biting problems.