UK Puppy Growth Tool

Dog Weight Calculator

Estimate your puppy's adult dog weight using age, current weight, and size class. Use it as a puppy weight calculator, dog size calculator, and puppy growth calculator in one.

How big will my puppy get? How much will my dog weigh? When do puppies stop growing?
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Estimate Adult Dog Weight

Tip: best estimates usually come from puppies older than 8 weeks.

Your result will appear here.

Quick Dog Weight Converter (kg/lb)

Converted value appears here.

How to Use This Puppy Weight Calculator

  1. Choose your unit in kg or lb, then enter your puppy's current weight.
  2. Enter age in weeks or months and select a breed size class.
  3. Click calculate to get estimated adult weight range, midpoint, and confidence.

This works as a dog weight estimator, dog size predictor, and puppy growth calculator in one tool.

Puppy Weight Chart by Age (Adult Weight %)

Use this dog growth chart as a quick benchmark. Your calculator estimate is personalised and usually more useful than a generic puppy weight chart.

Estimated percentage of adult weight reached
Age Small Medium Large Giant
8 weeks25%18%13%10%
4 months55%43%32%26%
6 months82%66%52%42%
9 months95%82%67%55%
12 months100%93%79%66%

Tip: If your puppy is outside the expected chart pattern, track weekly changes and speak with your vet.

How Big Will My Puppy Get? Growth Guide

Last updated:

This dog weight predictor estimates adult size using age-based growth curves for four classes. It calculates the percent of adult weight already reached, then projects a realistic range.

Small Dogs

Faster early growth and earlier maturity. Most reach near-adult size by around 8-12 months.

Medium Dogs

Steady growth pattern with most weight gain slowing by 12 months.

Large Dogs

Longer growth period. Weight often continues to increase until 15-18 months.

Giant Dogs

Longest growth curve. Some giant breeds keep filling out until roughly 18-24 months.

Breed examples: Yorkie, Chihuahua, Labrador, German Shepherd, Golden Retriever, and Great Dane puppies can all follow different growth rates even inside the same size class.

Dog Weight Calculator FAQ

How accurate is this estimate?

It is an informed estimate, not a diagnosis. Accuracy depends on breed genetics, diet, activity, and health. The best window is usually 12-40 weeks.

How big will my puppy get?

Use your puppy's current weight, age, and size class. The calculator returns an adult range plus a midpoint. This is a practical puppy size estimator, not an exact final value.

When do puppies stop growing?

Small breeds often finish by 8-12 months, medium breeds around 12 months, large breeds 15-18 months, and giant breeds can continue up to 24 months.

How much will my dog weigh?

You get an estimated adult range in kg and lb, plus a midpoint. The midpoint is useful for planning food portions and tracking growth trends over time.

Can I use this as a puppy weight chart alternative?

Yes. Standard puppy weight charts are generic, while this tool uses your age and current weight inputs to give a tailored estimate.

Can this predict exact adult weight?

No calculator can guarantee exact adult size. Use the provided range and consult your vet for personalised guidance.

Does this work for mixed-breed dogs?

Yes, but mixed breeds can vary more. Choose the closest size class based on expected adult frame.

Is this a dog size calculator and dog growth calculator too?

Yes. It functions as a dog weight calculator, dog size predictor, and puppy growth calculator using one unified model.

Medical disclaimer: This website is for educational use only and does not replace veterinary advice.

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