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Pet Calculators

Puppy Adult Weight Predictor

Verified formula Updated Jun 2026 Private — runs on your device

Enter details
kg
weeks
Verified formula Private

Estimated adult weight

21.7

For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.

How to use the Puppy Adult Weight Predictor

The Puppy Adult Weight Predictor works out your estimated adult weight in an instant. Enter current puppy weight and current age and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.

  1. Enter the current puppy weight.
  2. Enter the current age.
  3. Read off your estimated adult weight — the calculator updates automatically, with no button to press.

Formula

The Puppy Adult Weight Predictor uses the formula:

Estimated adult weight = Current puppy weight ÷ Current age × 52

Worked example

For example, with current puppy weight of 5 kg and current age of 12 weeks, the estimated adult weight is 21.7.

Inputs used
Current puppy weight 5 kg
Current age 12 weeks
Results
Estimated adult weight 21.7

Results are estimates for educational use, not professional advice.

Frequently asked questions

A simple estimate divides current weight by age in weeks and multiplies by 52. A 5 kg puppy at 12 weeks may reach about 21.7 kg.

It is a rough guide. Breed, sex and genetics matter, so use it as a ballpark rather than an exact figure.

Yes. Small breeds finish growing sooner, while large breeds keep growing for many months, so the estimate works best around mid-puppyhood.

Small breeds often reach adult size by about 9–12 months; large breeds may keep growing to 18 months or more.

The Puppy Adult Weight Predictor uses the formula: Estimated adult weight = Current puppy weight ÷ Current age × 52. For example, with current puppy weight of 5 kg and current age of 12 weeks, the estimated adult weight is 21.7.

Enter the current puppy weight. Enter the current age. Read off your estimated adult weight — the calculator updates automatically, with no button to press.

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