Animal Gestation Due Date Calculator
Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer
Last updated: July 28, 2026Animal Gestation Due Date Calculator
Expecting a litter or foal? This calculator estimates a due date based on breeding date and species-specific gestation length.
Reference Average Gestation Lengths
Dog: 63 days | Cat: 64 days | Horse: 340 days | Cow: 283 days | Goat: 150 days | Rabbit: 31 days
Example
A dog bred on day 100 of the year:
Due Day = 100 + 63 = Day 163
Why This Is an Average, Not a Precise Prediction
These are average gestation lengths - actual gestation length varies by several days in either direction depending on the individual animal, breed, and litter or offspring size, meaning the true due date can reasonably fall a few days before or after this calculated estimate.
Veterinary Monitoring Near the Due Date
This estimate should be confirmed and monitored by a veterinarian as the estimated due date approaches, since ultrasound or radiograph-based dating and monitoring near term gives much more precise timing and helps identify any complications before delivery.