Dog Size Calculator
🐾 Trusted by 50,000+ Pet Parents

Predict Your Puppy's
Adult Size

Our advanced breed-specific calculator uses growth data from veterinary research to accurately predict how big your puppy will get.

Start Calculating
50+
Breeds Supported
95%
Accuracy Rate
5
Size Categories
A beautiful golden retriever puppy sitting in warm sunlight
🐾 Premium Tool

Dog Size Calculator

Enter your puppy's details below to get an accurate prediction of their adult weight and size category.

🐕 Puppy Details

How old is your puppy? Predictions work best from 8 weeks onward.
Weigh your puppy after a meal for the most consistent reading.
Selecting a breed uses its specific growth curve for a more precise prediction.
Males are typically 5-10% heavier than females of the same breed.

Fill in your puppy's details to instantly see predictions

Medium Breed
Predicted Adult Weight
0.0
Expected range: 0 – 0 lbs
Predicted Height (paw to shoulder) —
Size Comparison
Toy
Small
Med
Large
Giant
🐾 Interactive Guide

How It Works

Four simple steps to discover your puppy's predicted adult size - watch the diagram come alive as you use the calculator.

1

Choose Breed

Select your dog's breed category or specific breed from our database

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2

Enter Details

Input your puppy's current age in weeks and their weight

→
3

Smart Analysis

Our algorithm uses breed-specific growth curves from veterinary data

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4

Get Prediction

View your dog's predicted adult weight with an interactive growth chart

🐾 Watch a Medium Breed Grow

Drag the slider to see how a puppy grows from 8 weeks to adulthood

8 wks
Age
13.5 lbs
Weight
30%
Growth
🐾 Reference Guide

Dog Size Categories

Understanding the five standard size categories helps you plan for nutrition, exercise, and supplies.

Toy

Under 10 lbs
Chihuahua · Pomeranian · Maltese · Yorkie · Toy Poodle

Small

10 – 25 lbs
Beagle · French Bulldog · Corgi · Dachshund · Cavalier

Medium

25 – 55 lbs
Border Collie · Bulldog · Aussie · Poodle · Samoyed

Large

55 – 100 lbs
Labrador · Golden Retriever · German Shepherd · Boxer · Husky

Giant

100+ lbs
Great Dane · Mastiff · Saint Bernard · Newfoundland · Wolfhound
🐾 Common Questions

Frequently Asked

Everything you need to know about predicting your puppy's adult size.

How accurate is the dog size calculator?
Our calculator uses breed-specific growth curves derived from veterinary research data. For purebred dogs, accuracy typically falls within 10% of the actual adult weight. Mixed breeds may have more variation due to unpredictable genetic factors. The prediction becomes more accurate as your puppy gets older.
What age should I use the calculator?
You can use it for puppies as young as 8 weeks old. However, predictions become significantly more accurate after 12-16 weeks. For giant breeds, we recommend waiting until at least 16 weeks for the best estimates, as their growth patterns take longer to establish.
Does this work for mixed breeds?
Yes! For mixed breeds, select the size category that best matches what you believe your dog's adult size will be based on their parents. If you know one parent's breed, use that breed's size category. The results may have a wider range than purebred predictions.
Why do different breed sizes grow at different rates?
Toy and small breeds reach their adult weight much faster (around 10-12 months), while giant breeds can continue growing until 18-24 months. This is because larger dogs have more skeletal and muscle mass to develop. Their growth plates also take longer to close, which is why nutrition during this period is especially important.
How is the predicted weight calculated?
We use interpolated growth percentage tables for each size category. At any given age, a puppy has reached a specific percentage of their adult weight. By dividing the current weight by this percentage, we can estimate the adult weight. The growth curves follow an S-shaped pattern based on real veterinary growth data.
Should I be worried if my puppy is above or below the prediction?
Not necessarily. Individual dogs can vary significantly even within the same breed. Factors like genetics, nutrition, exercise, and health conditions all play a role. We show a range rather than a single number for this reason. If you're concerned about your puppy's growth, consult your veterinarian for a Body Condition Score assessment.