Irish Terrier Puppy Weight Calculator

Calculate the adult weight for your Irish Terrier. Just type your puppy’s current weight and age, and see how big your puppy gets.

Irish Terrier Breed Profile & Growth Guide

Breed Overview

The Irish Terrier is one of the oldest terrier breeds, originating from Ireland, where it was developed as a versatile farm dog—used for hunting, guarding, and companionship. With its wiry red coat, spirited personality, and fearless nature, the Irish Terrier became known as the “daredevil” of the canine world. Despite their boldness, they are deeply loyal and affectionate with their families.

Irish Terriers are intelligent, independent, and energetic. They require consistent training and plenty of mental stimulation but reward their owners with devotion and charm. Their high prey drive means they may not always do well with small animals, but they can coexist peacefully with other dogs if properly socialized.

Size Category: Medium
Irish Terriers fall into the medium-sized breed category, with adults typically weighing 25–27 lbs and standing 18–19 inches tall. Because they are lean, athletic dogs with rapid early development, tracking their growth is important to ensure they reach healthy weight milestones without over- or underfeeding.

For more on the breed, visit the AKC Irish Terrier page.

Irish Terrier Growth Chart & Weight Ranges

Age	Male Weight (lbs)	Female Weight (lbs)
4 weeks	2.5 – 3.5	2.0 – 3.0
8 weeks	5.5 – 7.5	5.0 – 7.0
3 months	9 – 12	8 – 11
4 months	12 – 15	11 – 14
6 months	17 – 20	15 – 18
9 months	21 – 24	19 – 22
12 months	24 – 27	22 – 25

Note: Males typically weigh 2–3 lbs more than females, though both grow at a fairly consistent pace.

How Much Bigger Will My Irish Terrier Puppy Get?

Irish Terrier puppies grow quickly during the first 6–8 months, and most will reach their full height and close to adult weight by the end of their first year.

• 50% of adult weight by 4 months
• 75% by 6 months
• Full adult size by 10–12 months

Rule of thumb:
Double your Irish Terrier’s weight at 16 weeks to estimate their adult weight.

Exceptions:
While most Irish Terriers stop growing in height by 10–12 months, some may continue to fill out and gain muscle through 14–15 months.

For more breed-specific resources, consult the Irish Terrier Club of America.

Irish Terrier Growth Tips

Nutrition

• Feeding Schedule: 3 meals per day until 6 months, then reduce to 2 meals.
• Feed a balanced medium-breed puppy food that supports healthy muscle and bone development.
• Avoid overfeeding—Irish Terriers are naturally lean, and excess weight can lead to joint stress and reduced agility.

Exercise

• Irish Terrier puppies are high-energy and curious. Provide multiple short play sessions throughout the day.
• Avoid repetitive high-impact activities like stair running or jumping until 9–12 months.
• Include mental stimulation such as training games, puzzle toys, and scent work.

Health Watch

• Hip dysplasia: Less common than in large breeds but still worth screening if lameness occurs.
• Patellar luxation: May occur in some terriers—watch for signs like skipping or limping.
• Dental care: Like many terriers, they can be prone to tartar buildup; start brushing early.