Dog Heat Cycle Calculator

🐶 Dog Heat Cycle Calculator – Track Your Dog’s Heat, Fertility & Cycle Timeline

Managing your dog’s reproductive health can feel confusing, especially if you’re a first-time dog owner or Breeder. Our Dog Heat Cycle Calculator makes the whole process easier by helping you predict your dog’s next heat, fertile window, heat end date, and potential due date if breeding occurs.
This smart online tool uses the average canine heat cycle timeline to give you accurate estimates based on your dog’s last heat start date.

For more pet-care tools and helpful health trackers, explore our full collection of animal and lifestyle calculators.

🔍 What Is the Dog Heat Cycle Calculator?

The Dog Heat Cycle Calculator is an online tool designed to help dog owners accurately track their female dog’s heat cycle.
It helps you estimate:

• ✔ Next heat cycle date

• ✔ Fertile window (best days for breeding)

• ✔ End of the current heat

• ✔ Estimated due date (if your dog becomes pregnant)

A typical dog heat cycle lasts around 21 days and repeats every 6 months. This calculator uses these average biological patterns to give you a reliable prediction.

Whether you’re planning breeding, avoiding pregnancy, or monitoring your dog’s reproductive health, this tool gives you fast and accurate results.

You can also go through - Rotunda Due Date Calculator

⚙️ How the Dog Heat Cycle Calculator Works

Female dogs go through a heat (oestrus) cycle roughly every 6 months, though this varies by breed and age.
The cycle includes:

1. Proestrus – bleeding begins (Day 1–9)

2. Estrus (Fertile Period) – ovulation/fertility days (Day 9–14)

3. Diestrus – heat ends (around Day 21)

4. Anestrus – resting period until the next cycle

The calculator uses your dog’s last heat start date and applies:

• 180 days → next heat estimate

• Day 9–14 → fertile window

• Day 21 → heat end

• 63 days after ovulation → estimated pregnancy due date

This gives you a clear and predictable heat cycle timeline.

📝 How to Use the Dog Heat Cycle Calculator

Using the calculator is simple:

1. Select your dog’s last heat start date (the first day you noticed bleeding).

2. Click Calculate.

3. Instantly see:

   • Next expected heat date

   • Fertile breeding days

   • Heat ending date

   • Estimated due date (if pregnant)

You don’t need any additional information. The tool handles all calculations automatically.

⭐ Why Use This Dog Heat Cycle & Fertility Calculator?

Here’s why this is one of the most useful tools for dog owners:

✔ Accurate results — based on veterinary averages

The calculator applies scientifically accepted cycle averages.

✔ Great for breeders & responsible pet owners

Plan mating, whelping, or avoid unwanted pregnancies.

✔ Saves time & avoids guesswork

No need to manually track each stage of the dog heat cycle.

✔ Useful for small, medium & large breeds

Works for all dogs, though heat frequency may vary.

✔ Helps maintain your dog’s reproductive health

Knowing the cycle timeline helps you monitor behaviours, appetite changes, swelling, and fertility signs.

❓ Dog Heat Cycle Calculator – Frequently Asked Questions (FAQ)

1. How often do dogs go into heat?

Most female dogs go into heat every 6 months, though small breeds may cycle every 4 months and large breeds every 9–12 months.

2. How long does a dog’s heat cycle last?

A typical heat lasts 18–21 days, including proestrus, estrus, and diestrus.

3. When are dogs most fertile during heat?

Dogs are most fertile between Day 9 to Day 14 of the heat cycle. This calculator highlights the fertile window for breeding.

4. Can this calculator tell me when my dog will get pregnant?

It cannot confirm pregnancy but can estimate the due date (63 days after ovulation) if mating happens.

5. Can the calculator help avoid accidental pregnancy?

Yes — by knowing when your dog enters her fertile days, you can take precautions to prevent unwanted litters.