Dog Heat Cycle Calculator
Predict next heat cycle and fertile window
Calculator
Predict Heat Cycle
Enter the start date of your dog's last heat cycle to see predictions.
Frequently Asked Questions
How often do dogs go into heat?
Most dogs cycle every 6 months (twice a year). Small breeds may cycle every 4–5 months. Large and giant breeds every 8–12 months. The first heat usually occurs between 6–24 months of age.
When is the best time to spay?
Traditional advice: before the first heat (6 months). Current research suggests larger breeds may benefit from waiting until 12–18 months for joint/growth plate development. Discuss timing with your vet based on breed and size.
Dog Heat Cycle Calculator
Predict your dog's next heat cycle, fertile window, and spay timing based on last cycle date.