Puppy Weight Calculator.

Key calculations

Adult Weight Estimation

Adult Weight = Current Weight / (Growth % at current age / 100) / Gender Factor. The growth percentage is based on size-category growth curves from veterinary studies.

Gender Adjustment

Female dogs typically reach 85-90% of male adult weight for the same breed or size category. The calculator uses a factor of 0.875 for female puppies.

Growth Curve Interpolation

For ages between measured data points (4, 8, 12, 16, 20, 24, 28, 36, 44, 52 weeks), the growth percentage is linearly interpolated between the nearest known values.

Range Estimation

The minimum and maximum range is calculated as ±15% of the point estimate, then constrained by breed-typical weight ranges where available.

Height Estimation

If a current shoulder height is provided: Estimated Adult Height = Current Height / (Growth % at current age / 100) / Gender Factor. If no measurement is provided, height is estimated from expected adult weight using allometric scaling: Height ≈ k × Weight^(1/3), where k is a size-category constant calibrated from breed standards.

Length Estimation

Body length follows the same logic as height. When the user enters a current body length, it is projected to adult length using the growth curve. Otherwise, it is estimated allometrically from the weight estimate with a size-category scaling constant.

Reference ranges

Toy Breeds (under 18 lbs)

Examples: Yorkie, Chihuahua, Shih Tzu, Pug. Shoulder height 5–13 in, body length 7–15 in. Reach adult size fastest, typically by 9–12 months. Growth curve flattens earliest.

Small Breeds (18–32 lbs)

Examples: French Bulldog, Dachshund, Cavapoo, Cockapoo. Shoulder height 8–15 in, body length 10–17 in. Reach adult size by 10–14 months.

Medium Breeds (32–55 lbs)

Examples: Beagle, Corgi, Bulldog. Shoulder height 10–15 in, body length 14–18 in. Reach adult size by 12–16 months.

Large Breeds (55–95 lbs)

Examples: Golden Retriever, Labrador, German Shepherd, Husky, Boxer, Standard Poodle, Goldendoodle. Shoulder height 18–26 in, body length 20–31 in. Reach adult size by 15–24 months.

Giant Breeds (95+ lbs)

Examples: Rottweiler, Great Dane, Mastiff. Shoulder height 22–27+ in, body length 25–31+ in. Reach adult size the slowest, by 18–30 months. Growth curve extends beyond 52 weeks.

How to use it

1. 1.Choose purebred or mixed breedSelect Purebred if you know your puppy's breed, or Mixed Breed if your puppy is a mix. This determines which growth curve is used.
2. 2.Select breed or size categoryFor purebred, pick from 19 popular breeds in the dropdown. For mixed breed, choose the expected adult size: Toy, Small, Medium, Large, or Giant.
3. 3.Enter age and weightInput your puppy's current age in weeks and current weight in pounds. Use the slider for age or type directly. For best accuracy, weigh your puppy on a reliable scale.
4. 4.Read the estimateThe estimated adult weight, shoulder height, and body length appear instantly along with min-max ranges. The growth curve chart shows expected weight at each developmental stage from 4 to 52 weeks.
5. 5.Add height/length (optional)Enter your puppy's current shoulder height (floor to withers) and body length (chest to tail base) in the optional fields below the weight input. These measurements improve accuracy for height and length estimates. Leave blank for automatic allometric estimates.
6. 6.Download or printClick Print Report to open the print dialog where you can save as PDF. The printed report includes your inputs, the estimate, growth curve, and a disclaimer.