Dog Size Calculator by Age
Here’s a comprehensive table that summarizes dog size by age, providing all the essential information you need to know about a dog’s growth:
| Age | Toy Breeds (<12 lbs) | Small Breeds (12-22 lbs) | Medium Breeds (22-57 lbs) | Large Breeds (57-99 lbs) | Giant Breeds (>99 lbs) |
|---|---|---|---|---|---|
| 8 weeks | 1-3 lbs | 2-6 lbs | 5-10 lbs | 10-20 lbs | 15-30 lbs |
| 3 months | 2-4 lbs | 4-10 lbs | 10-20 lbs | 20-35 lbs | 30-50 lbs |
| 4 months | 3-5 lbs | 6-12 lbs | 15-25 lbs | 30-45 lbs | 45-70 lbs |
| 6 months | 4-7 lbs | 8-16 lbs | 20-35 lbs | 40-60 lbs | 60-100 lbs |
| 9 months | 5-8 lbs | 10-18 lbs | 25-45 lbs | 50-75 lbs | 80-130 lbs |
| 12 months | 6-10 lbs | 11-20 lbs | 30-50 lbs | 60-90 lbs | 90-150 lbs |
| 18 months | Fully grown | Fully grown | Fully grown | Nearly fully grown | Still growing |
| 24 months | Fully grown | Fully grown | Fully grown | Fully grown | Fully grown |
Key Points to Remember:
- Growth Rate: Smaller breeds typically reach their full size faster than larger breeds14.
- Maturity Age:
- Weight Prediction: You can estimate an adult dog’s weight using this formula: (Puppy weight / Puppy age in weeks) × 522.
- Height: Maximum height varies by size category, ranging from about 12 inches for toy breeds to 44 inches for giant breeds2.
- Lifespan: Generally, smaller dogs tend to have longer lifespans than larger dogs23.
- Senior Age: Smaller dogs are considered seniors later in life compared to larger breeds. For example, small dogs become seniors around age 10-12, while giant breeds may be considered seniors by age 5-63.
- Mixed Breeds: For mixed breed dogs, you can estimate their final size by looking at their paw size around 6 months of age5.
Remember that these are general guidelines, and individual dogs may vary. Factors such as nutrition, health, and genetics can influence a dog’s growth rate and final size. Always consult with a veterinarian for specific advice about your dog’s growth and development.