Updated
Dog pregnancy calculator
A due date from a mating date is a window, not a day: mating can precede ovulation by several days and sperm survives up to a week, so the honest answer from mating alone is 58–68 days. If you have an ovulation date from a progesterone test, enter it and the window tightens to 62–64. Milestones and the "call the vet" dates are worked out as dates, not day numbers you have to count.
3 November 2026 expected due date
Window 29 October 2026 to 8 November 2026. From mating on 1 September 2026: 58–68 days, 63 expected.
- Earliest
- 29 October 2026
- Latest
- 8 November 2026
- Day 25 — 26 September 2026
- Veterinary confirmation: ultrasound or palpation from about day 25–28; relaxin test from about day 25
- Day 45 — 16 October 2026
- X-ray can count puppies from about day 45
- Day 56 — 27 October 2026
- Start twice-daily rectal temperature: a drop below 37.8 °C (100 °F) usually comes within 24 hours of labour
- Day 58 — 29 October 2026
- Prepare the whelping area; labour can begin from day 58
- Day 68 — 8 November 2026
- No labour by this day (day 68 from the last mating): call the vet
- Day 70 — 10 November 2026
- Still no labour: this is an emergency
- During labour
- Call the vet for 30 minutes of hard straining without a puppy, more than 2 hours between puppies, or a green discharge before the first puppy.
What this means
Gestation is close to 63 days from ovulation, but a mating can happen days before or after the egg is released and sperm lives up to a week inside the bitch, so counting from mating gives a spread of ten days. That is not the calculator being vague — it is the biology. A progesterone test pins ovulation and pins the date.
With several matings, the earliest possible birth counts from the first and the latest from the last, which is why this page asks for both. Small dogs tend to whelp a day or two earlier than large ones; no source quantifies it, so this page does not either.
The milestones are the checkpoints the Merck Veterinary Manual gives, as dates: when a vet can confirm the pregnancy, when an X-ray can count the litter, and when to prepare. Breed, litter size and age offsets that some calculators apply are not sourced and are not used here.
When to see a vet
- No labour by day 68 from the last mating (day 65 from ovulation): call. By day 70, go.
- Thirty minutes of hard straining without a puppy, more than two hours between puppies, or a dark green discharge before the first puppy.
- Any bleeding, foul discharge, collapse or fever at any point in the pregnancy.
Formula and sources
Sources reviewed 18 September 2026. Each names the figure it supports.
- Dog gestation windows (58–68 days from mating; 62–64 from ovulation), milestones and the whelping temperature drop — Merck Veterinary Manual, "Management of Reproduction: Dogs"
- Cat gestation (63–65 days typical, 58–72 possible), induced ovulation, milestones — Merck Veterinary Manual, "Management of Reproduction: Cats"
- Gestation 63 ± 1 days from ovulation (65 ± 1 from the LH surge) in the bitch — Concannon P. W., "Reproductive cycles of the domestic bitch", Animal Reproduction Science 124(3–4), 2011
This page is an educational estimate, not veterinary advice.
Frequently asked questions
When is my dog due?
About 63 days after mating, but honestly anywhere from 58 to 68: enter the mating date above for the window as dates. If you have an ovulation date from a progesterone or LH test, enter that instead and the window narrows to 62–64 days.
First mating or last mating?
Both. The earliest possible birth counts from the first mating and the latest from the last, because any of the matings could have been the one that conceived. Enter the first in the first field and the last in the second; for a single mating leave the second blank.
How accurate is a due date from a progesterone test?
Within a day or two. Gestation is 63 ± 1 days from ovulation and 65 ± 1 from the LH surge (Concannon 2011), so a test that identifies ovulation gives a far tighter window than any mating date can.
When should I call the vet during a dog pregnancy?
If there is no labour by day 68 from the last mating (65 from ovulation), call; by day 70 it is an emergency. During whelping: 30 minutes of hard straining with no puppy, more than 2 hours between puppies, or a green discharge before the first puppy.