Dog Heat Cycle Calculator
Dog Heat Cycle Calculator
Track and predict your female dog’s heat cycles with breed-specific accuracy. Plan veterinary visits, breeding, or prevent unwanted mating.
Enter Your Dog’s Information
Provide your dog’s last heat start date and breed information for accurate predictions.
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Calculating cycle information…
Cycle Timeline Visualization
This calculator provides estimates only. Individual dogs may have irregular cycles, especially young or aging females. Always consult your veterinarian for breeding decisions, health concerns, or if you notice unusual symptoms.
Care Tips
- • Use dog diapers during bleeding phase
- • Supervise outdoor time during fertile window
- • Monitor behavior and appetite changes
- • Keep male dogs away during estrus
Normal Variations
- • First heat: 6-24 months of age
- • Cycle length: 4-12 months typically
- • Stage durations can vary by individual
- • Stress can affect timing
Table of Contents
A dog’s heat cycle, also known as the estrous cycle, is the reproductive cycle of an unspayed female dog. It typically occurs every six months, but this can vary widely between individual dogs and breeds. The entire cycle lasts approximately 18 to 28 days and is divided into four distinct stages.
The Four Stages of the Dog Heat Cycle Calculator
1. Proestrus
This is the first stage of the heat cycle, and it lasts for an average of 9 days. It’s the period when a dog’s body prepares for mating. Key signs include a swollen vulva and a bloody discharge. During this stage, a male dog will be attracted to the female, but she will not be receptive to mating.
2. Estrus
This is the fertile window and is when the dog is ready to mate. It typically lasts for an average of 9 days. The discharge will lighten in color, and the dog will often present her rear to male dogs, sometimes moving her tail to the side. Ovulation usually occurs during the first few days of this stage. The most fertile period is generally considered to be from Day 10 to Day 14 after the first sign of heat.
3. Diestrus
This stage follows the fertile period and lasts for about 60 days. The body’s progesterone levels rise, whether or not the dog becomes pregnant. If she does conceive, this is the gestation period, and the puppies will be born at the end of this stage. A false pregnancy can also occur during this period.
4. Anestrus
This is the period of reproductive rest. It lasts for approximately 4 to 5 months before the next cycle begins. The body is in a state of hormonal quiescence, and there are no signs of sexual activity.
Key Considerations
- Timing is Crucial: For breeders, knowing the exact timing of the estrus stage is critical. The most accurate way to pinpoint ovulation is through progesterone testing performed by a veterinarian.
- Whelping Date: The average gestation period for a dog is 63 days from the day of ovulation.
- Variations: The timelines provided are averages. Some dogs, particularly larger breeds, may only go into heat once a year, while some smaller breeds might cycle three times a year.
