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Puppy Weight Calculator

Growth curves by breed sizeProjected weight milestonesWorks 8–52 weeks of age
Enter Puppy DetailsFree · Instant
Predicted Adult Weight
Predicted Adult Weight
14.8
lbs (6.71 kg)
Current Growth
54%
of adult size
Growth Progress
0%54% (now)100% adult
Projected Growth Milestones
AgeEst. Weight (lbs)% of Adult
8 wks5.940%
12 wks854%
16 wks9.665%
20 wks1174%
24 wks11.880%
32 wks13.390%
40 wks14.296%
52 wks (1 yr)14.8100%

How Adult Weight Is Predicted

Growth % = breed-size curve lookup for age in weeks
Predicted Adult Weight = Current Weight ÷ (Growth% / 100)

Growth curves vary significantly by breed size. Toy breeds reach 80% of adult weight by 16 weeks; giant breeds may only be at 42% by the same age. The calculator interpolates linearly between known data points.

Who Is This Calculator For?

🐶
New Puppy Owners
Find out roughly how big your puppy will grow to plan food, crate, and space needs.
🏥
Veterinarians
Quick reference for expected weight trajectories during wellness visits.
🏡
Rescue Coordinators
Estimate adult size of mixed-breed puppies for adoption listings.
🎾
Dog Trainers
Plan training intensity and equipment sizing based on projected adult weight.

How to Use This Calculator

1
Select breed size
Choose the category that best matches your puppy's expected adult size based on breed.
2
Enter current weight
Weigh your puppy accurately in pounds. A baby scale works well for small breeds.
3
Enter current age in weeks
Enter age from 8 weeks (typical adoption age) up to 52 weeks.
4
Read the predicted adult weight
The result shows predicted adult weight in lbs and kg.
5
Check the growth progress bar
See what percentage of adult size your puppy has reached.
6
Review the milestone table
See estimated weight at every major age checkpoint from 8 to 52 weeks.

Worked Example

Jake just adopted Milo, a 12-week-old Border Collie mix (medium breed). Milo weighs 9 lbs at the vet. How big will he get?

Breed size: Medium
Current weight: 9 lbs at 12 weeks
Medium breed growth at 12 weeks: ~54% of adult weight
Predicted adult = 9 ÷ 0.54 = 16.7 lbs

What Does the Result Mean?

Milo is predicted to reach about 16.7 lbs as an adult. Jake can use this to choose the right crate size now, plan food portions, and set expectations with the vet. Note that genetics and sex can shift the actual weight by 10-15%; females typically run slightly smaller.

Common Mistakes to Avoid

!
Using the wrong breed size category
Selecting 'small' for a dog that will be 'medium' throws off the entire prediction. When in doubt, go one size larger.
!
Weighing right after a meal
Post-meal weight can add 10–20% error on small puppies. Weigh before meals for consistency.
!
Treating the prediction as exact
Genetics, sex, and diet all affect final size. A 10–15% variance from prediction is entirely normal.
!
Using this for dogs over 52 weeks
This calculator covers puppy growth up to 1 year. Adult dogs require different estimation methods.
!
Ignoring that females run smaller
Female dogs typically run 10–15% smaller than males of the same breed. The prediction assumes average sex.

Frequently Asked Questions

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Sources & References

Body-Weight Changes During Growth in Puppies of Different Breeds. Journal of Nutrition, 2004.
Hawthorne AJ et al. · pubmed.ncbi.nlm.nih.gov
Canine Weight Estimation and Breed Prediction Methods. Veterinary Medicine, 2011.
Metzger FL et al. · avma.org
Breed Weight Charts and Growth Guidelines
American Kennel Club · akc.org
Reviewed By
Dr. Claire Foster, DVM
Veterinarian, small animal medicine, 11 years in practice

Dr. Foster runs a small animal veterinary clinic in Colorado and specializes in puppy wellness and preventive care. She has reviewed this calculator to ensure the growth curve data reflects current veterinary standards.

Breed Size Guide
Toy
2–6 lbs, matures by 9 months
Small
8–20 lbs, matures by 12 months
Medium
20–50 lbs, matures by 14 months
Large
50–90 lbs, matures by 18 months
Giant
90–200 lbs, matures by 24 months
💡 Pro Tip

For mixed-breed puppies, weight prediction is less reliable. Your best estimate comes from knowing the breed sizes of both parents. If unknown, ask your vet: foot size and bone structure offer additional clues.

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