What Is the Guinea Pig Pregnancy Calculator?
This tool estimates when your pregnant guinea pig (a "sow") is likely to give birth. Guinea pig gestation is one of the longest among small rodents, averaging about 68 days but ranging from roughly 59 to 72 days. Enter the date of mating and the calculator projects the expected due date along with an earliest and latest delivery window.
How to Use It
Select the date your guinea pig was bred. The default gestation length is 68 days, which is the commonly cited average, but you can adjust it between 59 and 72 days based on your vet's guidance or breed. The calculator instantly returns the estimated due date and a likely birth window so you can prepare a safe, quiet birthing area.
The Formula Explained
The core calculation is simple date arithmetic: $$\text{Due Date} = \text{Mating Date} + 68 \text{ days}$$ Because individual pregnancies vary, the tool also shows a window from 9 days before to 4 days after the average due date, reflecting the natural 59–72 day spread.
Worked Example
If your guinea pig was mated on January 1, 2024, adding 68 days gives a due date of March 9, 2024. The earliest likely birth would be around February 29, 2024 and the latest around March 13, 2024.
FAQ
How long are guinea pigs pregnant? Typically 59–72 days, averaging about 68 days — much longer than most rodents.
How many pups will there be? Litters usually range from 2 to 4 pups, though first litters can be smaller and larger litters occur.
When should I see a vet? Always consult an exotic-pet vet during pregnancy, especially for first-time sows over 8 months old, as the pelvic bones may fuse and complicate delivery.
