Dog Pregnancy Calculator
Estimate the whelping date and follow a dog's pregnancy week by week.
About the Dog Pregnancy Calculator
Enter the mating date to see the expected whelping date and the normal window around it, so you can prepare a whelping box and plan vet checks.
Dog pregnancy lasts about 63 days from ovulation; counted from mating it can be 58–68 days because sperm survives several days and eggs mature after ovulation. Progesterone testing by a vet pinpoints ovulation and narrows the window.
The formula
Due date ≈ mating date + 63 days (range 58–68)
Worked example
Mated on 1 January 2026
- 1 January + 63 days = Thursday 5 March 2026
- Normal window: about 28 February to 10 March
Questions people ask
When should I call the vet?
If active straining lasts over 30–60 minutes without a birth, or there's green discharge with no newborn.
Should I change the diet?
Switch to a growth/puppy or kitten food in the last third of pregnancy, on vet advice.
How is a dog's pregnancy confirmed?
By ultrasound from about 25 days, or a blood test for relaxin from about 4 weeks.