Average gestation lengths
| Animal | Average (days from breeding) |
|---|---|
| Dog | 63 (about 58–68) |
| Cat | 65 (about 63–67) |
| Rabbit | 31 (about 28–35) |
| Goat | 150 (about 145–155) |
| Sheep | 147 (about 142–152) |
| Pig | 114 (about 111–117) |
| Cow | 283 (about 279–287) |
| Horse | 340 (about 320–370) |
These are typical averages. Breed, litter size and the exact day of ovulation all move the real date. In dogs, for example, sperm can live for several days, so the date of mating is not always the date of conception, and that is why the range is wide.
Making the estimate more accurate
- If your vet measured the progesterone level or the LH surge, ask them for a due date based on ovulation; it is far more precise than the mating date.
- An ultrasound or X-ray later in pregnancy can confirm the timing and the litter size.
- Write down every mating date; use the first one here and expect the birth toward the later end of the range if matings continued.
This is an estimate, not veterinary advice. Ask your vet to confirm the pregnancy and the due date, and call them right away if the animal shows signs of distress or the due date passes without labour.
Frequently asked questions
How long is a dog pregnant?
About 63 days from ovulation. Counted from the mating date, normal births happen roughly between day 58 and day 68.
Can I know the due date if I don't know the mating date?
Not with this calculator. A vet can estimate how far along the pregnancy is with an ultrasound or X-ray.
Why does my horse go past 340 days?
Mare pregnancies vary a lot; births from about 320 to 370 days are common. Ask your vet if you are worried.
Sources
Last reviewed: November 2026 · By Muhammad Shujah