Maine Coon Size Guide: The Truth About the ‘Largest Domestic Cat’#

If you spend five minutes on Instagram/TikTok, you’ve seen them: Maine Coons that look the size of a mountain lion, held by a person who is struggling to stay upright.

As the owner of Atticus (who tips the scales at 22lbs), I can confirm: they are huge. But I also need to be the voice of reason. A lot of those viral photos are using “forced perspective” (holding the cat way out in front of the camera) to make them look 4 feet long.

However, the reality is still impressive. When Atticus stretches out on the sofa, he takes up two full cushions. When he stands on his hind legs (which he does to inspect the kitchen counters), his paws easily reach my waist.

If you are researching the breed because you want a “monster” cat, you need to understand the genetics, the realistic expectations, and the difference between “healthy big” and “obese big.”

The Realistic Numbers (No Hype)#

Let’s look at the data. I track weight stats from TICA breeder reports and my own vet records.

Weight#

Males: 15 – 25 lbs (6.8 – 11.3 kg)
Females: 10 – 15 lbs (4.5 – 6.8 kg)

Note: A 15lb female Maine Coon is still much larger than a regular cat (which averages 8-10lbs). But if you are expecting a 30lb cat, you are looking for a statistical outlier (or a very fat cat).

Length#

This is where the breed truly shines.

Average Length: 30 – 40 inches (nose to tail tip).
The Record: The Guinness World Record for longest cat usually hovers around 47-48 inches, and it is almost always a Maine Coon.

A Maine Coon standing next to a normal cat showing significant height difference — Even a 'small' Maine Coon towers over a standard domestic cat.

The “Slow Burn” Growth Cycle#

When I got Penelope, she was a tiny 3lb fluff ball. I panicked when she didn’t explode in size immediately.

Here is the secret: Maine Coons grow slowly. A standard cat is fully grown by 12 months. A Maine Coon keeps growing until age 4 or even 5.

Year 1: They get their height (the “lanky teenager” phase).
Year 2-3: They “fill out” (muscle development and chest breadth).
Year 4: The coat reaches full “breeding plumage” (the ruff becomes magnificent).

Do not judge your cat’s final size until they are blowing out the candles on their 4th birthday.

Is Bigger Always Better?#

There is a toxic trend in the Maine Coon world called “Size Chasing.” Breeders who breed only for size often neglect health.

Joint Issues: A 30lb frame puts immense pressure on hips. Hip Dysplasia is a real risk.
Heart Strain: The heart has to pump blood through that massive body. Extreme size can correlate with shorter lifespans if the heart (HCM) isn’t monitored.

I love Atticus at 22lbs, but I honestly worry about his joints as he ages. I keep him on Glucosamine supplements religiously. My advice? Look for a healthy, proportionate cat, not a scale-breaker.

Resources & Further Reading#

TICA Breed Standard: Official Weight & Size Descriptions.
Guinness World Records: Longest Cat Living (Barivel).
PetMD: Growth Charts for Large Breed Cats.