Dog pregnancy calculator: when are the puppies due?
This dog pregnancy calculator turns the date you know — the first mating, the LH surge or ovulation from your vet’s progesterone tests, or the first day of diestrus — into a typical due date, the normal whelping window and a week-by-week calendar. It also shows how many days pregnant your dog is today and what to prepare before the birth.
Dogs are pregnant for about nine weeks, but the date of mating is a poor guide on its own. Sperm can survive in the female for a week or more, so conception may happen days after the mating. That is why the window from a mating date is wide (58 to 72 days) while the window from a hormone-timed ovulation is only a few days. The figures come from the Merck Veterinary Manual chapters on whelping and breeding management.
Use the dates to plan, not to wait. If anything worries you during the pregnancy or the birth, call your vet.
How to use the Dog Pregnancy Calculator
- Choose which date you know: first mating, LH surge, ovulation or the first day of diestrus.
- Enter the date. If she was mated more than once, add the last mating date too.
- Read the typical due date, the normal window and the line telling you which day and week she is in today.
- Check the key dates — when a scan or X-ray works best and when to start temperature checks.
- Use the week-by-week calendar and the checklist to prepare, and press Copy dates to save them.
Dog Pregnancy Calculator features
Four starting points
Mating, LH surge, ovulation or diestrus, each with its own published gestation length and window.
Today’s day and week
Shows how far along she is now and how many days remain to the typical due date.
Animated timeline
A bar with the whelping window, the due date and today’s position.
Vet milestones
Palpation, relaxin test, ultrasound and X-ray timing from the Merck Veterinary Manual.
Whelping checklist
What to have ready and the warning signs that mean you should call your vet now.
How long are dogs pregnant?
Source: Merck Veterinary Manual, “Whelping and Queening in Dogs and Cats” and “Breeding Management of Bitches” (both reviewed June 2025; checked October 2026). The ovulation row is derived: ovulation follows the LH peak by two to three days. The 63 days used for a mating date is the figure usually quoted; Merck notes that breeding dates do not predict whelping accurately.
Example: mated on 1 January 2026. Day 63 is 5 March, and the normal window runs from 28 February (day 58) to 14 March (day 72). If she was mated again on 4 January, the end of the window moves to 17 March.
| Date you know | Typical | Normal range |
|---|---|---|
| First mating (breeding) | 63 days | 58–72 days |
| LH surge (progesterone rise) | 65 days | 64–66 days |
| Ovulation | 63 days | 61–64 days |
| First day of diestrus | 57 days | 56–58 days |
Confirming the pregnancy
Source: Merck Veterinary Manual, “Pregnancy Determination in Dogs and Cats”. Day numbers here are counted from about the time of ovulation, so they are approximate when you start from a mating date.
- Feeling the abdomen: small swellings in the uterus form by about day 21 and a vet may feel them in a relaxed dog.
- Relaxin blood test: reliable after about 22–27 days.
- Ultrasound: best at 25–35 days; earlier than day 21 it can miss a pregnancy.
- X-ray: skeletons appear at about days 42–45; after day 55 is best for counting puppies, which helps you know when the last one has arrived.
Feeding and care during pregnancy
Most dogs need no extra food in the first six weeks. In the last three weeks energy needs rise sharply — the AAHA nutrition guidelines use about three times the resting energy requirement — so increase the amount gradually, ideally with a puppy or growth food your vet recommends. The dog food calculator has a “pregnant, last 3 weeks” setting. Keep up gentle walks, avoid rough play and jumping late on, and ask your vet before giving any medicine or worming treatment.
If you are planning a litter, think about the parents’ relationship as well as the dates: the coefficient of inbreeding calculator works out how closely related a planned pairing is. To predict when she will next come into season, use the dog heat cycle calculator.
Dog Pregnancy Calculator FAQ
How long is a dog pregnant?
About 63 days — nine weeks — from ovulation. From a mating date the normal range is 58 to 72 days, because conception can happen days after mating.
How does a dog pregnancy calculator count days?
It adds the published gestation length to the date you enter: 63 days after the first mating, 65 after the LH surge, 63 after ovulation or 57 after the first day of diestrus, and shows the normal window around it.
How can I tell if my dog is pregnant?
Early signs are subtle. A vet can confirm pregnancy by ultrasound from about day 25, with a relaxin blood test after about day 22–27, or by X-ray later on.
When should I worry during whelping?
Call your vet if she strains strongly for 30 minutes without a puppy, goes more than 2 hours between puppies, labours for 4 hours without the first puppy, has dark green or foul discharge before the first puppy, or is still not in labour by about day 70 after mating.
Does the temperature drop before whelping?
Usually. Merck reports a drop to about 37.1 °C (98.8 °F), usually 8–24 hours before whelping. Take her rectal temperature twice a day in the last week.
Is this calculator veterinary advice?
No. Ask your vet — this is general information, not veterinary advice. Timing from a mating date is approximate; progesterone testing gives much more precise dates.