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Rat Terrier Growth Chart

Male adult weight10–25 lb4.5–11.3 kg
Female adult weight10–20 lb4.5–9.1 kg

Rat Terriers are sturdy, all-American farm terriers. Adults typically weigh 10–25 lb, with males heavier than females. Most reach adult weight around 12 months.

View weight chart (lb & kg)

Calculate Your Rat Terrier Puppy's Adult Weight

Enter your Rat Terrier puppy's age and current weight for an estimated adult weight range.

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Rat Terrier weight by age

Typical male and female puppy weight ranges by age, available in lb and kg. Individual puppies may vary.

Most Rat Terrier puppies approach adult weight around 11 months, although individuals may finish earlier or later.

Weight unit
Expected Rat Terrier puppy weight at key ages in lb or kg
AgeTypical male rangeTypical female range
2 months (8 weeks)1.8–7.7 lb0.8–3.5 kg1.8–6.1 lb0.8–2.8 kg
3 months (12 weeks)2.7–10.1 lb1.2–4.6 kg2.7–8.1 lb1.2–3.7 kg
4 months (16 weeks)3.6–12.2 lb1.6–5.5 kg3.6–9.7 lb1.6–4.4 kg
5 months (20 weeks)4.4–14.2 lb2–6.4 kg4.4–11.3 lb2–5.1 kg
6 months (24 weeks)5.1–16 lb2.3–7.3 kg5.1–12.8 lb2.3–5.8 kg
7 months (32 weeks)6.5–19.5 lb2.9–8.8 kg6.5–15.6 lb2.9–7.1 kg
9 months (40 weeks)7.8–22.8 lb3.5–10.3 kg7.8–18.2 lb3.5–8.3 kg
1 year (52 weeks)9.1–25 lb4.1–11.3 kg9.1–20 lb4.1–9.1 kg

These estimated ranges combine the breed's adult weights with a size-based growth curve. They are not measured breed-specific percentiles or health targets. Month labels are rounded approximations; use the week values for each row. How these weight ranges are calculated

Rat Terrier Growth Stages

Understanding the typical growth stages helps you know what to expect as your Rat Terrier puppy grows.

Neonatal

0–2 weeks

Puppies are born with eyes and ears closed, relying entirely on their mother. Rapid weight gain occurs during this period.

Socialization

3–12 weeks

Eyes and ears open. Puppies begin to explore, play, and learn social behaviors. This is a critical period for development.

Juvenile

3–6 months

Rapid growth continues. Puppies become more independent, start teething, and develop coordination.

Adolescent

6–10 months

Growth rate begins to slow. Puppies reach sexual maturity and may test boundaries. Muscle mass develops.

Young Adult

10–12 months

Growth is nearly complete. Your puppy is filling out and approaching adult proportions.

Adult

12+ months

Your puppy has reached their full adult size. Weight should remain relatively stable with proper nutrition.

Rat Terrier FAQ

How much will my Rat Terrier puppy weigh as an adult?

Most adult Rat Terriers typically weigh between 10 and 25 lb. Males often land in the 10–25 lb range, while females may finish lighter at 10–20 lb. Toy and miniature varieties run smaller.

At what age is a Rat Terrier fully grown?

Rat Terriers usually reach adult weight around 12 months.

How accurate is a Rat Terrier puppy weight chart?

Charts show typical trends, not guarantees. This breed has real size variety — confirm whether your puppy comes from standard or miniature lines.

Do male and female Rat Terriers grow differently?

Males are stockier, often a few pounds heavier than females.

How much should I feed my Rat Terrier puppy?

Feed measured meals of a quality puppy food. Rat Terriers are active, muscular little dogs — fuel the muscle, not the fat. Ask your vet about portions.

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