Puppy Weight Predictor

Estimates a puppy’s adult weight by dividing current weight by the percentage of adult maturity at the current age. Small breeds mature by ~52 weeks, large breeds by ~60, and giant breeds by ~80 weeks. Shows predicted adult weight with ±15% range, percentage of adult weight currently achieved, and growth timeline by breed size category.

Puppy Weight Predictor
Fun & planning tool.

Puppy Weight Predictor

Estimate your puppy’s adult weight based on current weight, age, and breed size.

RESULT

The puppy weight predictor estimates your puppy’s adult weight based on current weight, age in weeks, and breed size category. Small breeds reach adult weight by ~52 weeks; giant breeds take up to 80 weeks.

How the Prediction Works

Adult Weight = Current Weight / (Age in Weeks / Maturity Weeks) Maturity Weeks by Size: Toy/Small: ~52 weeks (1 year) Medium: ~52 weeks (1 year) Large: ~60 weeks (14 months) Giant: ~80 weeks (18–20 months)

Growth by Size Category

Size Adult Weight Full Size By
Toy Under 10 lbs 9–12 months
Small 10–20 lbs 10–12 months
Medium 20–50 lbs 12–14 months
Large 50–80 lbs 14–18 months
Giant 80+ lbs 18–24 months

Puppy Weight Predictor FAQ

How accurate is the puppy weight predictor?

Within ±15% for purebreds, less accurate for mixed breeds. The prediction improves as the puppy gets older — a prediction at 16 weeks is more reliable than at 8 weeks.

When is the best age to predict adult weight?

12–16 weeks gives a reasonable estimate. By 6 months (26 weeks), most dogs have reached 60–75% of adult weight, making predictions more accurate.

Do male and female puppies differ?

Males are typically 10–20% heavier than females of the same breed. If you know the sex, expect males toward the upper range and females toward the lower range of the prediction.

My puppy is a mixed breed — can I still use this?

Yes, but accuracy is lower. Choose the size category that best matches the expected adult size based on the parents. If parents are unknown, the vet can estimate based on paw size and bone structure.

When do puppies stop growing?

Small breeds finish by 10–12 months. Medium breeds by 12–14 months. Large breeds by 14–18 months. Giant breeds may continue growing until 18–24 months.

Is this puppy weight predictor free?

Yes, completely free. Enter current weight, age, and breed size for an instant adult weight estimate.

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