Medium breed

Border Collie Growth Chart

Male adult weight30–45 lb
Female adult weight27–42 lb

Border Collies are intense herding dogs with a lean frame and fast metabolism. Most approach adult weight by 12–15 months. High activity can keep puppies looking slim while they still gain height and bone—track weight weekly for context.

Border Collie weight by age

Typical weight ranges based on Border Collie adult size and standard growth curves. Individual puppies may vary.

Expected Border Collie puppy weight at key ages (lb)
AgeExpected weight (low–high)
8 weeks4.212.8 lb
12 weeks6.316.4 lb
16 weeks8.219.5 lb
20 weeks1022.5 lb
24 weeks11.625.2 lb
32 weeks14.730.4 lb
40 weeks17.735.3 lb
1 year21.842.2 lb
1y 26w24.845 lb

Calculate Your Border Collie Puppy's Adult Weight

Enter your Border Collie puppy's age and current weight for an estimated adult weight range.

Age
Current weight
Sex
100% free · No sign-up required · US-based estimates

Enter your puppy's details to see the estimate

Border Collie FAQ

How much will my Border Collie puppy weigh as an adult?

Enter your puppy's age and current weight in this calculator. Typical adult Border Collie ranges depend on sex, genetics, and whether the puppy is on a steady growth curve.

At what age is a Border Collie fully grown?

Most Border Collie dogs reach most adult weight between 10 and 18 months depending on size. Larger individuals may keep filling out slightly longer while bone and muscle finish developing.

How accurate is a Border Collie puppy weight chart?

Charts reflect typical trends, not guarantees. Individual puppies may finish above or below the estimated range based on parents, nutrition, and overall health.