Maine Coon Size & Growth Guide: Height, Weight, Length & Development Stages
Maine Coons are one of the largest domesticated cat breeds in the world, but their size varies more than most people realise.
This hub gives you a complete overview of Maine Coon size, average weight ranges, growth stages, how long they grow, and how to track healthy development – with links to detailed, specialist guides throughout the page.
Whether you’re raising a Maine Coon kitten or comparing adult size ranges, this guide brings every important measurement together in one place.
How Big Are Maine Coon Cats?
Maine Coons are famous for their impressive bodies, muscular build, and long rectangular frames. Adult males typically reach their full size between 3-5 years old, while females often mature slightly earlier. Their large paws, long torso, fluffy tail, and thick double coat create the iconic “big cat” look.
For a full breakdown of weights, lengths, and height measurements, see:
Average Weight Of A Maine Coon
Maine Coons weigh significantly more than the average domestic cat. Genetics, diet, activity level, and neutering status all influence weight, but healthy ranges are well-established.
For the most accurate ranges, growth patterns, and a complete male vs female comparison, visit:
This article includes helpful tables, common weight myths, and how to tell whether your Maine Coon is underweight or overweight.
Maine Coon Growth Chart (Week-By-Week & Month-By-Month)
Unlike most cats, Maine Coons grow slowly and steadily for several years. Many owners don’t realise that Maine Coons often continue filling out long after they reach their full height or length.
Kittens grow rapidly during the first 9 months, then enter a slower developmental phase that can last until age 5.
For full charts, timelines, and healthy weight expectations by age:
This is your core reference for tracking a kitten’s development and ensuring they stay on a healthy trajectory.
When Do Maine Coons Stop Growing?
Maine Coons reach different growth milestones at different times because their skeletal structure, coat development, and muscle mass all mature at different speeds.
Most will reach:
- Full height around 1-1.5 years
- Full length around 2-3 years
- Full weight/muscle mass between 4-5 years
For a complete breakdown of the timeline and what influences it, read:
Why Some Maine Coons Are Bigger (Or Smaller) Than Average
Every Maine Coon is unique, and several factors determine adult size:
- Genetics & lineage
- Diet quality
- Early-life nutrition
- Exercise levels
- Gender
- Neutering age
- Health conditions
If your Maine Coon seems unusually small or slow to grow, compare against healthy growth curves and nutrient recommendations here:
Is Your Maine Coon Overweight?
Because they’re naturally big cats, owners often struggle to judge when a Maine Coon is overweight. Excess weight places strain on joints, hips, and the heart – especially in a breed already prone to hip dysplasia and HCM.
Learn how to check for obesity using body-condition scoring and photos:
This guide includes step-by-step visual checks and safe weight-loss strategies.
Comparing Maine Coon Size To Other Breeds
If you want to see how Maine Coons compare with other large cat breeds, such as Norwegian Forest Cats, Ragdolls, Siberians, or Savannahs, explore your comparison guides:
- Maine Coon vs Norwegian Forest Cat
- Maine Coon vs Siberian
- Maine Coon vs Ragdoll
- Maine Coon Size Compared to Humans
These help reinforce breed size expectations and eliminate common misconceptions.
Human-To-Cat Size Visual Comparisons
If you want to visualise scale, our “size compared to humans” guide provides:
- Height comparisons
- Typical body length charts
- Kitten vs adult visual markers
See the full visual guide:
Tracking Your Maine Coon’s Growth At Home
To monitor healthy development, owners can track:
- Weekly kitten weights (0-16 weeks)
- Monthly weights (4-12 months)
- Body length + tail length
- Height at the shoulders
- Body condition score (BCS)
For warning signs that growth may be lagging, slow, or excessive, refer to:
Essential Diet Guides For Supporting Growth
Diet has a major effect on Maine Coon size – high-protein, meat-based nutrition supports bone, joint, coat, and muscle development.
Internal articles that strengthen the owner’s understanding:
- Bottomless Bellies: How Much Do Maine Coon Cats Really Eat?
- How Much Do Maine Coon Kittens Eat?
- 6 Best Cat Foods That Reduce Shedding
Size & Growth FAQs
How big do adult Maine Coons get?
Males average 18-21 lbs, females 12-15 lbs, with body lengths up to 40 inches, including the tail.
When do Maine Coons stop growing?
Most reach full size between 4 and 5 years old.
How fast should a Maine Coon kitten grow?
They gain rapidly for the first 9 months, then slow until maturity.
Why is my Maine Coon small?
Genetics, early diet, illness, or mixed breeding can contribute.
Are male Maine Coons bigger than females?
Yes – males are typically heavier, taller, and broader.
