Guinea pig pregnancy calculator.
Find out when your guinea pig is due. Enter the mating date and the calculator estimates the due date from the average guinea pig pregnancy, with the earliest and latest dates too.
Mating date
LiveGuinea pig pregnancy lasts about 59 to 72 days, averaging near 68. The due date is the mating date plus the average gestation; the range gives the earliest and latest.
Estimated due date
Aug 8, 2026
based on average pregnancy
An estimate based on average guinea pig pregnancy; individual animals vary. Not veterinary advice. Calculations run in your browser; nothing you enter is stored.
How it works
Counting from mating
Guinea pig pregnancy lasts about 59 to 72 days from mating, about nine to ten weeks, with an average near 68 days. The calculator adds the average to the mating date to estimate the due date, and the 59 to 72 day range gives the earliest and latest you should expect pups.
Larger litters tend to be carried for slightly fewer days, and individuals vary. Treat the due date as a window of a few days rather than a single fixed day.
Reference
Gestation by animal.
Typical pregnancy lengths for guinea pigs and other common animals, for comparison.
| Animal | Gestation |
|---|---|
| Cat | 63 to 67 days |
| Dog | 58 to 68 days |
| Cow | 279 to 287 days |
| Goat | 145 to 155 days |
| Sheep | 144 to 152 days |
| Horse | 320 to 370 days |
The full guide
The complete guide to guinea pig pregnancy.
How long guinea pigs carry, the stages to expect, and when to get help.
How long are guinea pigs pregnant?
Guinea pig pregnancy runs about 59 to 72 days from mating, averaging around 68, or about nine to ten weeks. Counting from the mating date gives the most reliable estimate of when pups are due.
Larger litters tend to be carried for slightly fewer days, and individuals vary.
Stages of pregnancy
The sow gains weight steadily and her abdomen becomes very large in the second half, since guinea pigs often carry several large pups. In the final two to three weeks the pups can be felt moving.
Guinea pig pregnancy is unusually long for a small rodent, and the pups are born well developed, with fur and open eyes.
Preparing for the birth
Provide a clean, low-stress hutch with plenty of vitamin C in the diet, and avoid handling the sow heavily in late pregnancy. No nesting box is needed, as the pups are precocial and active soon after birth.
Keep the environment calm and warm in the final week.
When to call the vet
Seek veterinary help if she passes about 72 to 74 days, strains without producing a pup, or seems unwell. Sows first bred after roughly eight months of age are at higher risk of birth complications and need a vet’s guidance. This tool is for planning only and does not replace veterinary care.
The formula
Date plus
gestation.
The due date is the mating date plus about 68 days, with pups normally arriving between 59 and 72 days.
Rabbit gestation ›# Guinea pig due date
due = mating_date + gestation
guinea pig pregnancy = 59 to 72 days
# average 68 days
mating + 68 daysQuestions
Guinea pig pregnancy questions.
How long is a guinea pig pregnant?
+
About 59 to 72 days from mating, averaging around 68 days, about nine to ten weeks. The calculator uses this to estimate the due date.
How do I calculate a guinea pig due date?
+
Add about 68 days to the mating date. Enter that date above and the calculator gives the estimated due date plus the earliest and latest.
Can the due date be a few days off?
+
Yes. Larger litters tend to be carried for slightly fewer days, and individuals vary. Treat the result as a window from 59 to 72 days.
When should I contact a vet?
+
Contact a vet if the pregnancy runs well past 72 days, if labour stalls without progress, or if the animal seems distressed. A prenatal check-up is always worthwhile.
Is this guinea pig pregnancy calculator free?
+
Yes. It is completely free with no sign-up, and every calculation runs locally in your browser, so nothing you enter is stored or sent anywhere.
About the developer
Jean Borg
Jean builds and maintains every calculator on freecalculators.pro from Malta, with a focus on tools that are fast, free and show their working. The guinea pig pregnancy calculator estimates a due date from average guinea pig pregnancy and is for planning, not veterinary advice.