Cat Pregnancy Calculator
Due Date & Week-by-Week Timeline
Enter your cat’s mating date to get her due date, how far along she is today, what’s happening this week, and a complete pregnancy milestone calendar.
Cat Due Date Calculator
Enter the mating date and we’ll calculate the due date, show how far along your cat is today, and give you a week-by-week guide to what’s happening.
If your cat mated over multiple days, use the first date — it gives the earliest possible due date. Most cats deliver between day 63 and day 65 from the first mating.
Cat Pregnancy Stages — Week-by-Week Development Chart
A complete reference chart covering all nine weeks of feline pregnancy, with what’s happening inside, the signs you’ll see, and what to do at each stage.
Cat Gestation Chart — Week by Week
Average 63–65 days| Week | Days | Fetal development | Signs you’ll see | Action needed |
|---|---|---|---|---|
| Week 1 | 1–7 | Fertilisation and cell division. Embryos travel to the uterus. | None. Cat appears completely normal. | Nothing yet. Note the mating date. |
| Week 2 | 8–14 | Embryos implant in the uterine wall. Pregnancy hormones begin. | Possibly slightly more tired or affectionate. Most owners notice nothing. | Keep environment calm and low-stress. |
| Week 3 | 15–21 | Embryos are ~1 cm. Heart development begins. Organs start to form. | Pinking up — nipples enlarge and turn a distinctive rosy pink. First reliable sign. | Book vet appointment. Vet can confirm pregnancy by palpation or early ultrasound. |
| Week 4 | 22–28 | Rapid organ development. Heartbeats detectable by ultrasound. Fetuses ~2 cm. | Belly may look slightly fuller. Appetite often increases. Possible mild morning sickness (vomiting). | Vet visit — ultrasound confirms pregnancy and estimates litter size. Begin transitioning to kitten food. |
| Week 5 | 29–35 | Faces, ears, and whisker pads forming. Skeletal development accelerating. Fetuses ~4 cm. | Belly is clearly rounded. Weight gain visible. Breast tissue developing. Increased appetite. | Switch fully to kitten food. Increase food by 25–50%. Smaller meals more frequently helps if appetite is variable. |
| Week 6 | 36–42 | Fur developing. Claws forming. Gender differentiation occurs. Fetuses ~6 cm. | Belly is noticeably large and firm. Cat may groom her belly frequently. Kittens can sometimes be felt moving. | Set up a nesting box in a quiet, warm, low-traffic area. X-ray possible from day 42 to count kittens accurately. |
| Week 7 | 43–49 | Kittens close to fully formed. Fat depositing under skin. Lungs maturing. | Large abdomen. Visible kitten movement when cat is at rest. Appetite may begin to decrease as belly pressure increases. | Nesting box should be accessible. Feed smaller meals more frequently. Limit strenuous play. |
| Week 8 | 50–56 | Kittens fully developed and gaining weight. Milk production begins in the queen. | Nipples may leak small amounts of milk. Nesting behaviour intensifies. Restlessness. Some cats become more clingy. | Final vet check recommended. Prepare whelping supplies. Have vet emergency contact saved. |
| Week 9 | 57–65+ | Kittens are ready to be born. Birth most common from day 63–65. | Loss of appetite 24–48 hrs before labour. Body temperature drops below 37.8°C (100°F). Hiding, pacing, panting, vocalisations. | Stay available. Monitor from a distance. Call vet if straining for 30+ min without producing a kitten, or more than 2 hours between kittens. |
Signs of Cat Pregnancy — What to Look For and When
Cat pregnancy signs appear gradually. In the first two weeks there are usually none at all. By week three, the first reliable sign appears. Here’s what to watch for at each stage, in the order you’re likely to notice them.
How to Care for a Pregnant Cat
Cats are remarkably capable of managing their own pregnancies, but there are things owners can do — and a few things to avoid — that make the process safer and more comfortable for both the queen and her kittens.
- Switch to kitten food by week 4Kitten food is higher in protein, fat, and calories — exactly what a pregnant cat needs. Feed it throughout pregnancy and during nursing. A quality wet or dry kitten food is appropriate. Don’t restrict intake during pregnancy.
- Increase feeding gradually from week 5Feed 25 to 50% more than normal from week 5 onwards. From week 6, smaller and more frequent meals help because the growing uterus reduces stomach space. By late pregnancy, some cats prefer 4 to 5 small meals per day.
- Set up a nesting box by week 6A quiet corner of a room with a clean cardboard box lined with soft towels works well. The box should be large enough for the queen to stretch out, with sides low enough to step over. Keep it in a warm (24–27°C), low-traffic area away from other pets.
- Keep vet contact information ready from week 8Know your nearest 24-hour emergency vet. Complications during birth, while uncommon, can progress quickly. Having the number saved means you can act without hunting for information when it matters.
- Limit handling during late pregnancyIn weeks 7 to 9, avoid picking your cat up by the belly. Support her fully underneath when lifting is necessary. Keep children and other pets from bothering her, especially once nesting behaviour begins.
- No vaccinations or unnecessary medications during pregnancyLive vaccines should not be given during pregnancy. Many routine medications — flea treatments, dewormers, pain relievers — are not safe for pregnant cats. Always tell your vet a cat is pregnant before any medication is prescribed or administered.
- No calorie restriction during pregnancyEven if your cat was overweight before becoming pregnant, this is not the time to diet. Restricting calories in a pregnant cat risks fetal development problems and can trigger hepatic lipidosis. Weight management should wait until after weaning is complete.
Signs of Labour and When to Call the Vet
Most cats give birth without any problems and without needing help. But knowing what normal labour looks like — and what is not normal — means you can act quickly if something does go wrong.
- Restlessness, pacing, and hiding in the final 12–24 hours
- Loss of appetite the day before delivery
- Body temperature drops below 37.8°C (100°F) — 12–24 hrs before birth
- Excessive grooming, especially around the belly and vulva
- Panting or mild vocalisation during contractions
- Clear or slightly bloody vaginal discharge
- Visible contractions and straining
- Each kitten delivered within 10–60 minutes of the last
- Most litters born within 4–6 hours total
- Active straining for more than 30 minutes without producing a kitten
- More than 2 hours between kittens when you know more are due
- Bright green or black discharge before the first kitten is born
- Heavy, sustained bleeding (as distinct from small amounts mixed with discharge)
- A kitten stuck or partially born and not progressing
- Mother appears exhausted or has stopped straining despite being in labour
- Pregnancy past day 67 with no signs of labour
- Kitten born limp, not breathing, or making no sound
How to Set Up a Nesting Box for Your Pregnant Cat
A good nesting box makes delivery safer and gives you peace of mind. Set it up no later than week 6, give your cat time to get used to it, and place it somewhere she already likes to spend time.
Nesting box checklist — have this ready by week 7
Newborn kittens cannot regulate their own body temperature for the first few weeks of life. The nesting area needs to stay warm without being too hot — around 27°C for the first week, slightly cooler from week two onwards as the kittens start to develop some thermoregulation. Make sure there’s always a cooler part of the box they can move to if they overheat.
Cat Pregnancy Calculator — Frequently Asked Questions
Common questions about how long cats are pregnant, how to calculate the due date, what to expect during labour, and how to care for a pregnant cat.
The average cat pregnancy lasts 63 to 65 days from the date of mating — approximately nine weeks or just over two months. However, the normal range is wider than most people expect. Cats can deliver as early as day 58 or as late as day 70 and still have healthy kittens.
If your cat has not delivered by day 67 and shows no signs of labour, contact your vet. A pregnancy that extends past day 70 requires veterinary assessment to rule out complications.
If you know the mating date, simply add 63 to 65 days to it. Day 63 from mating gives you the average expected due date. Day 58 is the earliest reasonable delivery date and day 70 is the latest before you should contact your vet.
The calculator at the top of this page does this automatically and also shows how far along the pregnancy is today, what’s happening this week, and a full calendar of key dates to plan around.
If you don’t know the mating date, a vet can estimate how far along the pregnancy is using ultrasound (from day 21 onwards) or by measuring fetal size. X-ray from day 42 can confirm the number of kittens.
Yes. A queen can go into heat and become pregnant again as quickly as 1 to 2 weeks after giving birth, even while still nursing her current litter. This is sometimes called superfetation. It puts a significant physical strain on the mother cat.
To prevent back-to-back pregnancies, keep your cat indoors and completely separated from intact male cats during the nursing period. Spaying is the only reliable long-term solution and can be performed from around 8 weeks after birth in most healthy queens.
The first reliably visible sign is nipple pinking — the nipples enlarge and turn a noticeably rosier, pinker colour. This typically appears around days 15 to 21. Before this, there are usually no visible signs at all, even if the cat is definitely pregnant.
Other early signs that may appear in weeks 3 to 4 include a slight increase in appetite, increased affection or a change in energy levels, and occasionally mild morning sickness (vomiting once or twice). None of these individually confirm pregnancy — pinking up is the most telling physical indicator before the belly starts to grow.
You can estimate the stage from the physical signs you’re seeing. A rough guide:
- Nipples just pinking up, no belly change — probably weeks 2 to 3
- Slightly fuller belly, nipples clearly enlarged — probably weeks 4 to 5
- Clearly rounded belly, noticeably pregnant — probably weeks 5 to 6
- Large, firm belly, kittens possibly visible moving — probably weeks 7 to 8
- Nesting behaviour, milk production — probably week 8 to 9
The “estimate by signs” mode in the calculator above uses this approach. For a more accurate dating, take your cat to the vet — ultrasound measurements of fetal size give a reasonably precise gestational age estimate, especially between days 21 and 42.
The average litter size for domestic cats is 3 to 5 kittens, though anywhere from 1 to 8 is possible. First-time mothers tend to have smaller litters. The litter size can be estimated (though not always accurately) by your vet from around day 25 by ultrasound. A more accurate count is possible by X-ray from day 42 to 45, when the kittens’ skeletons are calcified enough to be visible.
Knowing the litter size before delivery is helpful — it tells you how many kittens to expect and helps you identify if the birth is complete or if more kittens remain.
The total time from the start of active labour to the birth of the last kitten is typically 4 to 16 hours. The first stage of labour — where the cat becomes restless, hides, and prepares the nest — can last 6 to 12 hours on its own, especially in first-time mothers.
Once active contractions begin, the first kitten usually arrives within 30 minutes of sustained straining. After that, kittens arrive every 10 to 60 minutes. A short rest between kittens is normal, and some cats eat, drink, and nurse earlier kittens between deliveries.
Newborn kittens cannot regulate their own body temperature for the first few weeks of life and are entirely dependent on external warmth. The nesting area should be kept at around 27 to 29°C (80 to 84°F) during the first week, reducing to about 24°C (75°F) by weeks 3 to 4 as the kittens begin to develop their own thermoregulation.
A heat lamp or heating pad placed on one side of the box (never underneath the entire box, so kittens can move away if too warm) works well. The mother cat normally generates enough warmth for the kittens when she’s with them. The risk increases if she leaves the nest for extended periods, particularly in the first two weeks.
Not immediately if she’s past day 63 but still within the normal range. The normal range for cat delivery is day 58 to day 70 from mating. Cats frequently deliver later than the day-63 average.
Contact your vet if your cat has not delivered by day 67 and shows no signs of labour, or immediately if she reaches day 70 without delivering. Prolonged pregnancy can sometimes indicate fetal death, obstruction, or other complications that require veterinary attention.
Also contact your vet straight away if she shows signs of straining without producing kittens, seems in distress, or has any discharge that is heavily coloured (dark green or black) before any kittens are born. Small amounts of dark discharge are normal after kittens are born, not before.
Calculate your cat’s due date
Use the calculator above. Enter the mating date to get the due date, this week’s development guide, and a personalised milestone calendar for your cat’s pregnancy.