Cat Pregnancy Due Date and Timeline Calculator
Cat pregnancy due date in days and weeks
This calculator estimates a cat’s expected due date based on a breeding date and a gestation length in days. You also get a practical timeline (weekly or daily), plus a progress chart and an exportable table.
How the calculation works
The core idea is simple: add the chosen gestation length to the breeding date.
Estimated due date uses:
\[ DueDate = BreedingDate + GestationDays \]
Due date window uses an uncertainty value:
\[ EarlyDue = BreedingDate + (GestationDays - Uncertainty) \]
\[ LateDue = BreedingDate + (GestationDays + Uncertainty) \]
Progress percent and days remaining
Progress is expressed as a percentage of the selected gestation length.
\[ Progress(\%)=\frac{DaysPregnant}{GestationDays}\times 100 \]
Days remaining is:
\[ DaysRemaining = \max(GestationDays - DaysPregnant, 0) \]
Week-by-week timeline and what to expect
The timeline is designed for common users. It includes general milestones such as early subtle changes, mid-pregnancy growth, nesting preparation, and the final days approaching labor. Use the uncertainty setting if the breeding date is not exact or if mating occurred across multiple days.
Important note
This tool is informational only. If your cat shows distress, prolonged overdue signs, bleeding, collapse, or you have any concern about labor, contact a veterinarian immediately.