Foaling Due Date Calculator
Enter a breeding or cover date for a typical ~340-day due date plus early and late watch window. No signup.
Breeding date
Typical gestation: 340 days (range 320–365).
When is my mare due to foal?
Breeders track gestation from the confirmed breeding or ovulation date. Because foals can arrive weeks early or late, plan supplies and foal watch for the full window—not just the single expected day.
Frequently asked questions
How long is a horse pregnant?
Average equine gestation is about 340 days (roughly 11 months), but healthy foals may arrive anywhere from about 320 to 365 days. Maiden mares and certain breeds sometimes run longer.
How do you calculate a foaling due date?
Count forward from the breeding or ovulation date. Most breeders use 340 days as the expected date, with a watch window from ~320 days (early) through ~365 days (late).
When should I start foal watch?
Many farms intensify monitoring around day 320–330, especially for mares with prior prematurity or dystocia history. Your vet can recommend mare-specific timing.
Does breeding method change gestation length?
Natural cover, AI, and embryo transfer can shift the reference date slightly. Use the date your vet confirms as ovulation or breeding for the most accurate window.
Is this foaling calculator medical advice?
No—it is an educational due-date window. Always work with your veterinarian for mare care, vaccinations, and foaling preparedness.