Guinea Pig Pregnancy Calculator
Enter the mating date to estimate when a guinea pig sow may give birth. The default uses a typical gestation of about 65 days and shows the commonly reported range. Treat it as a planning estimate, not a guaranteed date.
Last updated: September 25, 2026
Frequently asked questions
How long are guinea pigs pregnant?
Usually about 59 to 72 days, with an average around 65. That is much longer than most pet rodents.
Why is the range so wide?
Litter size, the individual sow, and uncertainty about the exact mating date all shift timing. Sows with larger litters may deliver earlier.
What if I do not know the exact mating date?
Use the earliest and latest possible dates to see the span of possible due dates.
When should I involve a veterinarian?
As soon as you suspect pregnancy. A vet experienced with small exotic pets can confirm it and advise on nutrition and risks, and should be contacted urgently if the sow seems distressed or the due window passes.
How is this different from the Cat or Dog Pregnancy Calculators?
It uses a guinea pig's gestation length, which is roughly a week longer than a dog's and more than a month longer than a cat's.
Can I change the gestation length?
Yes. Adjust the number of days if a veterinarian gives you a different estimate for your animal.