Dog & Cat Pregnancy Due Date Calculator
Predict whelping or queening date and plan the prenatal schedule. Most accurate from the canine LH-surge (± 1 day); useful enough from the mating date for cats and casual planning.
Species
Reference date
Wide range (58-71 days) because ovulation may happen days after mating.
Mating date
How to use this tool
Dog gestation timing
Canine gestation is remarkably consistent at 65 ± 1 days from the LH-surge, or 57 ± 1 days from the start of cytological dioestrus. From a mating date alone, the window widens to 58-71 days because sperm survives several days inside the bitch and ovulation may happen days after breeding.
Cat gestation timing
Queens are induced ovulators - ovulation follows successful mating. Expect 63-67 days from a confirmed breeding as the typical range, with absolute extremes 58-70 days.
Why ultrasound timing matters
Earliest reliable canine ultrasound is around day 22-24 for fetal cardiac activity, with the standard pregnancy check around day 28-30. For counting puppies, abdominal radiographs are far more accurate than ultrasound and can be taken once fetal skeletons mineralise (~day 42-45). For cats, ultrasound at day 21+ and radiographs at day 40+.
The pre-partum temperature drop
In dogs, rectal temperature drops below 37.2 °C (99 °F) approximately 12-24 hours before active labour. Twice-daily temperature checks in the last week are a useful predictor for breeders, especially with valuable litters or planned veterinary attendance.
Frequently asked questions
How long is a dog's gestation?
About 63 days from the LH-surge (most accurate), or 58-71 days from the first mating. The wide range from mating date is because sperm can survive several days, and ovulation may happen days after mating.
How long is a cat's pregnancy?
63-67 days on average from successful mating, with a normal range of 58-70 days. Queens can have post-coital ovulation, so the mating date is usually a good reference point.
Why is the LH-surge a more accurate due date than the mating date?
In dogs, oestrus length varies a lot between individuals. The LH-surge marks ovulation precisely, and whelping happens 63 ± 1 days later in nearly every case. From a mating date you can be off by a week or more.
What are the key prenatal milestones?
In dogs: cardiac activity detectable by ultrasound around day 22-24, fetal mineralisation visible on radiographs around day 42-45 (use to count fetuses pre-whelp), and the pre-partum temperature drop (below 37.2 °C / 99 °F) occurs 12-24 hours before labour.