Cat Pregnancy Calculator: Due Date & Gestation Calendar

How to use the cat pregnancy calculator

Add her name and breed (optional). The name personalizes your calendar events and PDF report.
Choose "Female (queen)". If you own the tom, choose "Male" and enter the dates for the female he mated.
Enter the first mating date. This is the only required field, and it counts as day 0.
Tick "Multiple days" and add the last mating date if she mated more than once. Queens often mate several times over a few days, so the first and last dates give a more honest due window.
Don't know the date? Switch on "I don't know the exact date" and pick the latest sign you've seen, such as pink nipples or a growing belly. You'll get a rough estimate to confirm with your vet.
Press Calculate. You'll see her due window, today's day and week of pregnancy, and a countdown.
Save the dates. Add each vet visit to Google Calendar, Outlook or Apple Calendar, or use "Add all dates" to save every date with a reminder the day before.
Download the PDF report with her pregnancy timeline, week-by-week guide, vet plan and labor checklist.

How the cat gestation calculator works

The calculator counts from the day of mating, the same way vets do. In a study of 1,056 litters from UK pedigree breeders, the average gestation was 65.1 days. [Sparkes et al., 2006] A research colony recorded an average of 66.9 days, with a range of 62 to 71 [Root et al., 1995], and most cats give birth between day 63 and 65. [VCA Animal Hospitals]

Cats are induced ovulators: mating triggers the release of eggs, so a queen usually mates several times during one heat, and one litter can even have several fathers. [Merck Veterinary Manual] [VCA Animal Hospitals] That is why a single "due day" is misleading, and why this tool asks for the first and last mating dates.

Likely due window = first mating + 63 days → last mating + 67 days

The calculator also shows the wider normal range, from first mating + 60 days to last mating + 70 days. Healthy pregnancies in a study of 52 Maine Coon litters ran from 60 to 72 days [Socha et al., 2019], and VCA gives 64 to 71 days. If she reaches day 71 with no sign of labor, call your vet.

Cat gestation table: due dates by mating date

Use this cat gestation table for a quick check if she mated on the 1st of a month. The dates assume a single mating day in 2026.

Mated on	Most likely due	Likely window (day 63–67)	Normal range (day 60–70)
Jan 1	Mar 7	Mar 5 – Mar 9	Mar 2 – Mar 12
Feb 1	Apr 7	Apr 5 – Apr 9	Apr 2 – Apr 12
Mar 1	May 5	May 3 – May 7	Apr 30 – May 10
Apr 1	Jun 5	Jun 3 – Jun 7	May 31 – Jun 10
May 1	Jul 5	Jul 3 – Jul 7	Jun 30 – Jul 10
Jun 1	Aug 5	Aug 3 – Aug 7	Jul 31 – Aug 10
Jul 1	Sep 4	Sep 2 – Sep 6	Aug 30 – Sep 9
Aug 1	Oct 5	Oct 3 – Oct 7	Sep 30 – Oct 10
Sep 1	Nov 5	Nov 3 – Nov 7	Oct 31 – Nov 10
Oct 1	Dec 5	Dec 3 – Dec 7	Nov 30 – Dec 10
Nov 1	Jan 5	Jan 3 – Jan 7	Dec 31 – Jan 10
Dec 1	Feb 4	Feb 2 – Feb 6	Jan 30 – Feb 9

Does breed or size change the due date?

Only slightly. In 52 Maine Coon litters the average gestation was 65.5 days, almost the same as the all-breed average. [Socha et al., 2019] In the UK study, breed averages ran from about 63 days in Korats to just over 66 days in Siamese and Oriental Shorthairs. [Sparkes et al., 2006] The differences are days, not weeks, so the calculator uses the same calendar for every breed.

Age matters more for litter size than for timing. Litters averaged 4.5 kittens in a Flemish study, but queens over four years old averaged 3.6 kittens against 4.8 in younger queens. [De Moor et al., 2019]

Add her weight under "More details" and the tool estimates her daily food needs. Pregnant cats need roughly 1.6 to 2 times their resting energy requirement. [AAHA, 2021] The cat calorie calculator explains the full method.

This page is the calculator. For the full guide to gestation, early signs and every stage, read how long are cats pregnant.

Cat pregnancy calendar: week by week

Your results highlight the week she is in now. Days are counted from the first mating (day 0). Signs vary from cat to cat, so treat these as typical, not fixed.

Week 1: Mating and fertilization (days 0–6)

Mating triggers ovulation, because cats are induced ovulators, and the eggs are fertilized in the day or so that follows. A queen often mates several times during one heat. No change you can see. Heat behavior fades over the next few days.

Write down every mating date. The first one is day 0.
Keep her indoors so no other tom can mate with her.

Week 2: Embryos reach the womb (days 7–13)

The tiny embryos travel down to the uterus and settle into its wall. Still no outward signs. Her heat cycles stop and do not come back.

Feed her usual food in her usual amounts. She does not need extra yet.
Book a vet visit for about three to four weeks after mating.

Week 3: Pinking up (days 14–20)

The embryos grow quickly and the placentas form. Her nipples turn pinker and more prominent, usually around day 15 to 18. This "pinking up" is often the first sign owners notice.

Keep her diet steady.
Give no new medicines, flea or worming treatments without your vet's approval.
Vet: Don't press her belly yourself. A vet can feel the pregnancy most easily from about day 21 to 25.

Week 4: Confirmation (days 21–27)

Each kitten now has its own sac and a heartbeat a scan can pick up. Her appetite starts to rise and her belly may begin to round out. Repeated vomiting is not normal and needs a vet.

Take her for the confirmation check three to four weeks after mating.
Keep her routine calm and her food steady while the pregnancy is confirmed.
Vet: Ultrasound is best from about day 25 (scans before day 21 can miss a pregnancy), and a vet relaxin blood test can pick it up from about day 20.

Week 5: Belly starts to show (days 28–34)

The kittens' claws, eyes and ears are forming. Weight gain and a rounder belly become easy to see, with a bigger appetite.

Ask your vet about moving her gradually onto a complete kitten food, and feed more as her appetite rises.
Avoid vaccines and parasite products unless your vet advises them.

Week 6: Rapid growth (days 35–41)

The kittens grow fast and their skeletons start to harden. Her belly is clearly larger. She eats more and sleeps more.

Offer small, frequent meals as her belly fills up.
Don't pick her up by the belly, and keep her surroundings calm.

Week 7: Movement (days 42–48)

The kittens' skeletons are now dense enough to show on an X-ray, from about day 42 to 45. You may feel or see kittens moving when she lies still. She slows down and rests more.

Choose a quiet, warm, draft-free spot for the birth box.
Keep her indoors and away from unneutered males and sick cats.

Week 8: Nesting (days 49–55)

The kittens are nearly fully formed. She looks for a quiet nest in cupboards and corners, and her mammary glands enlarge.

Have the birth box ready so she has time to choose it: towels or pads, with food, water and a litter box close by.
Save your vet's number and the nearest after-hours emergency clinic.
Vet: An X-ray after about day 55 gives the most reliable kitten count, so you know when she has finished.

Week 9: Final days (days 56–62)

Her body gets ready for labor. She is restless, grooms her belly and rear more, and may stop eating within a day of labor.

Keep the room quiet and the birth box ready.
Her rectal temperature may drop below about 100°F (37.8°C) in the last 24 hours, but this is not a reliable sign on its own.

Week 10: Birth window (days 63–70)

Most cats give birth between day 63 and 67. Nesting, pacing, panting and licking her rear mean labor is close.

Watch that a placenta follows each kitten, though not always straight away.
Weigh the kittens daily in the first week.
Vet: If she reaches day 71 with no sign of labor, call your vet.

Timings follow the Merck Veterinary Manual and veterinary references. [Merck Veterinary Manual] [Little, The Cat, 2012] [Vetstreet]

Vet visits during cat pregnancy

The calculator turns these into dated events you can add to Google Calendar, Outlook or Apple Calendar in one click.

As soon as you suspect pregnancy: a health check, parasite advice and a diet plan.
Three to four weeks after mating: a check to confirm the pregnancy. [VCA Animal Hospitals]
Day 25 to 35: the best window for an ultrasound. [Merck Veterinary Manual]
After about day 55: an X-ray for the most reliable kitten count. [Merck Veterinary Manual]
Within a day or two of the birth: a check for the mother and kittens.

Newborn kittens are most fragile at first: a review of feline neonatology reports that 91% of kitten losses happen in the first three days of life. [Veronesi & Fusi, 2022] Weigh the kittens daily in the first week and call your vet if one is not gaining.

Signs of labor in cats

Most cats give birth without help. Labor, called queening, has three stages: [Merck Veterinary Manual]

Stage 1, getting ready: restlessness, pacing, nesting, panting, licking her rear and often refusing food. It commonly lasts 12 to 24 hours.
Stage 2, delivery: visible straining and contractions, then a kitten, usually head or tail first. Kittens commonly arrive 30 to 60 minutes apart.
Stage 3, afterbirth: a placenta follows each kitten, though not always straight away. She often alternates between delivering kittens and placentas.
Delivery is ideally finished in about 7 to 9 hours. Many queens rest, groom and nurse between kittens.

When to call the vet straight away

A difficult birth, or dystocia, affects about 5% of cat and dog pregnancies. [Merck Veterinary Manual] Call your vet or an emergency clinic if:

She has strong contractions for more than 30 minutes without producing a kitten.
More than 2 hours pass between kittens with no contractions, when you know more kittens are inside.
You see dark green or foul-smelling discharge before the first kitten, or heavy fresh bleeding.
She reaches day 71 with no sign of labor.
She seems in severe pain, very weak, or a kitten looks stuck.

Cat pregnancy calculator FAQ

How long is a cat pregnant?

About 65 days on average, counted from mating. Most kittens arrive between day 63 and 67, and healthy pregnancies in studies have run from about 60 to 72 days. If she reaches day 71 with no sign of labor, call your vet.

What are the early signs that my cat is pregnant?

Her heat cycles stop first. Pinking up follows in the third week, usually around day 15 to 18, when her nipples turn pinker and more prominent. Her appetite rises and her belly starts to round in weeks 4 to 5. A vet check three to four weeks after mating confirms it.

When should I take my pregnant cat to the vet?

As soon as you think she may be pregnant, with a confirmation check three to four weeks after mating. An ultrasound is best from about day 25, and an X-ray after about day 55 gives the best kitten count. Go straight away if you see any warning sign during labor.

What should I feed a pregnant cat?

Vets usually recommend a high-quality kitten food during pregnancy and nursing, introduced gradually, with portions rising as pregnancy goes on. Pregnant cats need about 1.6 to 2.0 times their resting energy. Keep fresh water available and don't add supplements unless your vet advises it.

How many kittens will my cat have?

Litters average about 4 to 5 kittens: 4.6 in a UK study of 1,056 litters, and 4.5 in a Flemish study, where queens over four years averaged 3.6 against 4.8 in younger queens. An X-ray late in pregnancy is the reliable way to count them.

What is "pinking up" in cats?

Pinking up is when a pregnant cat's nipples become pinker and more prominent, usually around day 15 to 18. It is one of the earliest visible signs of pregnancy, but a vet should confirm it.

When is it too late to spay a pregnant cat?

There is no single cut-off date, and the right choice depends on the cat. Surgery becomes more involved as the pregnancy advances, so talk to your vet as early as possible.

What are the signs of labor in cats?

Restlessness, pacing, nesting, panting, licking her rear and often refusing food. Active labor starts when you see straining, and kittens commonly arrive 30 to 60 minutes apart.

Is this cat pregnancy calculator accurate?

It is as accurate as a date-based estimate can be. It uses the 65-day average from more than 1,000 litters and gives a window instead of one day. Entering both the first and last mating dates makes it more precise. Only a vet can confirm a pregnancy and how far along it is.

Can you tell the gender of kittens before they are born?

Not with a calculator or at home. Check each kitten's sex after birth, ideally with your vet at the first check.

Can a cat get pregnant again while nursing?

Yes. A queen can come back into heat while she is still feeding her kittens, and can get pregnant again within a week or two of giving birth. Keep her away from unneutered males and talk to your vet about spaying.

Sources

Sparkes AH, et al. (2006). A questionnaire-based study of gestation, parturition and neonatal mortality in pedigree breeding cats in the UK. Journal of Feline Medicine and Surgery. 1,056 litters from 14 breeds: average gestation 65.1 days, average litter 4.6.
Root MV, Johnston SD, Olson PN (1995). Estrous length, pregnancy rate, gestation and parturition lengths, litter size, and juvenile mortality in the domestic cat. JAAHA. Average gestation 66.9 days, range 62 to 71.
Socha P, et al. (2019). Obstetric and newborn parameters in the Maine Coon cats. Polish Journal of Veterinary Sciences. 52 litters: average 65.5 days, range 60 to 72.
De Moor J, Van Soom A, Wydooghe E (2019). Problems around parturition and neonatal mortality in pedigree cats: a study of Flemish breeders. Vlaams Diergeneeskundig Tijdschrift. 151 litters: average 4.5 kittens; 3.6 for queens over four years against 4.8 for younger queens.
Merck Veterinary Manual: Management of reproduction of cats. Induced ovulation, repeated matings, delivery 64 to 66 days after breeding, kitten food in pregnancy.
Merck Veterinary Manual: Pregnancy determination in bitches and queens. Palpation from about day 21, ultrasound best at day 25 to 35, skeletons on X-ray from day 42 to 45.
Merck Veterinary Manual: Labor, delivery and postpartum care in bitches and queens. Stage 1 lasts 12 to 24 hours; 30 to 60 minutes between kittens; delivery ideally done in 7 to 9 hours.
Merck Veterinary Manual: Dystocia in small animals. Dystocia affects about 5% of pregnancies; the warning signs.
Little SE. The Cat: Clinical Medicine and Management (2012), Female reproduction. Pinking up at day 15 to 18, relaxin from day 20, and return to heat while nursing.
Vetstreet: Pregnancy in cats. Day 63 most common; weight gain by weeks 4 to 5; claws, eyes and ears by week 5; avoid vaccines in pregnancy.
VCA Animal Hospitals: Breeding and queening cats. Gestation 64 to 71 days, most cats queen at day 63 to 65; feeding a pregnant cat; temperature before labor.
VCA Animal Hospitals: Estrous cycles in cats. One litter can have several fathers.
AAHA: 2021 Nutrition and Weight Management Guidelines, energy requirement calculations. Gestation factor for cats: 1.6 to 2.0 times resting energy.
Veronesi MC, Fusi J (2022). Feline neonatology: from birth to commencement of weaning. Journal of Feline Medicine and Surgery. Most kitten losses happen in the first three days of life.
Cats Protection: Care of pregnant cats. A mother can get pregnant again one to two weeks after giving birth.
Mar Vista Animal Medical Center: The feline spay. Spaying during pregnancy.

By Ahsan Nawaz

Published August 17, 2026 Updated October 9, 2026

This cat pregnancy calculator gives estimates based on published veterinary averages. It is not a diagnosis. Every cat is different: always confirm pregnancy, stage and litter size with your vet, and contact a vet immediately if you are worried during labor.

Cat Pregnancy Calculator: Due Date, Week-by-Week Calendar & Vet Plan

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