How long are dogs pregnant?
Counting from a single breeding date at an unknown stage of heat, Merck gives 58–72 days; counted from ovulation the range narrows to about 62–64 days. VCA cites an average of 63 days. [1][2][3]
How long are cats pregnant?
Merck's gestation table lists about 65 days for cats and its cat-owner chapter 60–65 days; VCA reports 60–67 days. [1][4]
Why the window is wide
Mating doesn't equal conception: sperm can wait for ovulation, and a single breeding date doesn't tell you exactly when the eggs were fertilized. Your vet can narrow the date with exams, hormone tests or imaging [2].