Enter your dog's Last Heat Start Date, Dog Size, Dog Age, and optional Breed to calculate her Next Heat Expected date, Fertile Window, Days Until Next Heat, and a heads-up on when to schedule a Recommended Vet Check.
Next Heat Expected
--
Fertile Window Start
--
Fertile Window End
--
Days Until Next Heat
--
Recommended Vet Check
--
Most female dogs go into heat every 6 months (twice a year). However, this can vary by size and breed - smaller dogs may cycle every 4-6 months, while larger breeds may have longer intervals of 8-12 months.
A complete heat cycle typically lasts 2-3 weeks. The cycle consists of four stages: proestrus (7-10 days), estrus (5-9 days), diestrus (60-90 days), and anestrus (2-5 months).
Dogs are most fertile during the estrus stage, typically 9-15 days after the heat cycle begins. This is when ovulation occurs and the female will accept mating.
Yes, dogs can be spayed during heat, but it's more complex and risky due to increased blood flow to reproductive organs. Many vets prefer to wait until after the heat cycle ends.
Signs include vaginal bleeding, swollen vulva, increased urination, behavioral changes (restlessness, clinginess), and attracting male dogs. Not all dogs show obvious bleeding.
Most dogs have their first heat between 6-12 months of age. Small breeds may start as early as 4 months, while giant breeds can wait up to 18-24 months.
This calculator helps predict fertile periods, but it's not 100% accurate for contraception. For pregnancy prevention, consult your vet about spaying or other reliable methods.
Yes, there are hormonal medications that can suppress heat cycles, but they carry health risks. The safest long-term solution is spaying. Always consult your veterinarian for the best option.