Small

Jack Russell Terrier Full Grown: Size & Weight

A full-grown Jack Russell Terrier weighs about 13–17 lb and stands roughly 10–15 in tall at the shoulder.

Have a Jack Russell Terrier puppy? Estimate its adult size

Built on the small growth curve, clamped to the breed's range.

Current age

Current weight

Jack Russell Terrier growth chart

How a small-size dog like the Jack Russell Terrier fills out over its first months. Switch between percent of adult weight and pounds, and enter a weigh-in above to plot your puppy.

Jack Russell Terrier
Your puppy

Median curves computed from ~89,000 healthy dogs aged 2–24 months in the open Salt et al. 2017 dataset (PLOS ONE, CC BY 4.0), grouped into PuppySize's five size classes.

Age	% of adult weight	Estimated weight
2 months	30%	4–5 lb
3 months	44.2%	6–8 lb
4 months	59.5%	8–10 lb
5 months	70.5%	9–12 lb
6 months	79.4%	10–13 lb
7 months	86.7%	11–15 lb
8 months	92.1%	12–16 lb
9 months	96.2%	13–16 lb
10 months	98.2%	13–17 lb
11 months	100%	13–17 lb
12 months	100%	13–17 lb

How confident is this estimate? Based on an official breed standard or cross-checked veterinary/registry sources.

About this breed's data: AKC splits this into two breeds: Russell Terrier (10-12 in) and Parson Russell Terrier (13-14 in). Weight 13-17 lb is from the Parson Russell standard and matches Hill's. Height range 10-15 in spans both.

Sources: AKC Official Standard of the Parson Russell Terrier (PDF, weight+height), AKC Official Standard of the Russell Terrier (PDF, height), Hill's Pet, Salt et al. 2017 (PLOS ONE) growth data.

How we calculate this

Jack Russell Terrier questions

How big does a Jack Russell Terrier get?

A full-grown Jack Russell Terrier typically weighs 13–17 lb and stands 10–15 in tall. Use the calculator above with your puppy's current age and weight for a personalized estimate.

When does a Jack Russell Terrier stop growing?

Most Jack Russell Terriers reach their full adult size around 12 months, in line with small-size dogs. They do most of their growing in the first 6 months, then fill out more slowly.

Are these Jack Russell Terrier size estimates accurate?

Based on an official breed standard or cross-checked veterinary/registry sources. Estimates are typically within 10–20% for purebreds; designer and mixed breeds vary more. We always show a range and clamp it to this breed's known adult size.