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Why Are Maine Coon Cats So Big? The size they really are

When a Maine Coon is born, it is similar in size to the average kitten. But then things change. The adorable ball of fluff that could fit in the palm of your hand grows, and grows and grows some more!

A Maine Coon’s proportions are not related to its food intake, though this can be a factor. We reveal three real reasons why Maine Coons are giants amongst most cats.

Maine Coons are big because they are genetically coded to develop a large musculoskeletal system. A large body size ensured their ancestors were robust enough to survive in a cold climate. However, today some Maine Coons are selectively bred to be big cats for a completely different reason.

A big red tabby Maine Coon with a fluffy tail held high.
Harry at 12 pounds in weight

Are Maine Coon cats really that big?

On average, Maine Coons are not really that big. If you’ve seen pictures of gigantic Maine Coons on social media, these are exceptional and not the norm.

It is easy to find reports of Maine Coons that weigh in excess of 30 pounds. Many of these cats are sadly overweight. In our experience, Maine Coons weigh between 12 and 18 pounds. Obviously, 18 pounds is a lot larger than the average cat but it’s a lot less than the legends have it.

If you have a Maine Coon and find it only weighs 12 or 13 pounds, you have a perfectly normal-sized Maine Coon, so don’t worry. Don’t feed it more to “help” it gain weight as this will result in an unhealthy cat.

Why today’s Maine Coons are selectively bred to be big

Breeders are sometimes asked if they sell large Maine Coons. Most tell prospective owners, quite rightly, that size cannot be guaranteed.

However, some breeders embark on a mission to produce kittens that they hope will satisfy the demands of those who want large Maine Coons.

When a large male and female are bred, there is a fair chance their kittens will grow to be large cats. If the largest cats from resultant litters are then bred with other large examples, some of these kittens will possibly be even larger than their parents.

Selective breeding through several generations can eventually lead to larger-than-average Maine Coons developing. This would not happen naturally and is only used as a means to meet demands.

That’s not to say that all big Maine Coons are the result of selective breeding. Some cats just turn out that way, even from the smallest of parents.

Fred: 14 pounds at 7 months of age

Are some Maine Coons all fur coat?

If you’ve ever seen a Maine Coon wringing wet, you’ll know that under all that fluff lurks a lean machine – sometimes a rather small one too.

A Maine Coon’s coat is capable of creating the illusion that it is a very large cat. In the winter it thickens up to make the cat look even bigger. By summer, it often looks somewhat smaller again.

How big is a full-grown Maine Coon?

A full-grown Maine Coon generally weighs between 12 and 18 pounds. There will always be some slightly less and some a little larger but the range is the same for males and females. In this particular breed, males are not necessarily larger than females.

Many people state that Maine Coons keep growing for up to 4 years. I won’t dismiss this out of hand but can say in our experience this is not the case.

We acquired a pair of Maine Coon kittens in 2005 and they didn’t get noticeably bigger after about 18 months. They gained a little more muscle and their coats filled out but they didn’t grow any longer, or taller.

We currently have a 2-year-old female who weighs 14 pounds. She weighed this much at 18 months when she came to live with us. We have another Maine Coon female who also weighs 14 pounds but is a little shorter in height.

Our two Maine Coon kittens, who are brothers are very different in size. At 9 months, one weighs 17 pounds and the other weighs 14 pounds. We will report their progress here, so don’t forget to come back and check.

It is impossible to predict the size any Maine Coon will be when it is fully grown, you’ll just have to wait and see. You could end up with one that’s 12 pounds, about the weight of an average house cat. You could find your Maine Coon grows to 18 pounds and even more.

Why some Maine Coons are smaller than expected

Occasionally a Maine Coon doesn’t quite make the mark. If one doesn’t reach 12 pounds, there are several reasons why.

Maine Coon mixes are smaller

There are many long-haired cats that look so similar to Maine Coons that it’s hard to tell them apart. Some of these are Maine Coon mixes and some have no Maine Coon genes at all. This is often a reason why someone believes they have a Maine Coon that’s smaller than average.

If you pay the price of a purebred Maine Coon, make sure you receive what you pay for. The best way to know is by using a recommended breeder who can prove their breeding cats are purebred and who also registers their kittens and hands over this paperwork.

Litter runts often don’t grow as big

When any kitten is born much smaller than the rest of the litter, it is referred to as a runt. This often happens in large litters and affects the kitten that was positioned in the narrowest part of the uterus.

Many runts catch up but occasionally they remain smaller than average when fully grown. This explains why some purebred Maine Coons are much smaller than average.

Malnutrition can lead to stunted growth in Maine Coons

Maine Coons need a good quality diet of protein balanced with essential nutrients found in bone and organ meat. When you buy cat food and it clearly states it is complete cat food, you know you are giving your cat everything it needs for a healthy diet.

A Maine Coon’s growth can be affected if it does not receive a complete diet. This might be because it strayed and lived wild or scavenged for a long time. Or it could be because it was fed just lean chicken and nothing else, therefore missing out on essential nutrients.

If you choose to make your own cat food, ensure you research the subject well so that your Maine Coon gets the right balance of nutrients to remain healthy and to grow at the correct rate.

Poor health can keep a Maine Coon small

Occasionally, poor health during its growing stage can lead to a Maine Coon not reaching its full-size potential. It is possible for a Maine Coon to recover from such an illness if it is diagnosed and treated.

If you suspect your Maine Coon is not growing as it should even though you are feeding it correctly, always take it to your vet for a full health check.

When a Maine Coon is big for the wrong reason

Some large Maine Coons are actually overweight. this can happen for a few reasons.

Too much food

It is easy to overfeed a Maine Coon, especially with dry food. If a Maine Coon is big because it is overweight, you can tell by looking at it from above. If it doesn’t dip in at the waist, just below its rib cage, this is a sure sign.

Make sure you feed your Maine Coon the right amount for its size. Most food packages have a guideline but a vet can give you good advice in this area.

It’s fine if a Maine Coon is big because it has a large frame and well-developed muscles, but not at all good if it’s because it is carrying fat!

Too little exercise

Indoor cats often have less opportunity to exercise so ensure you provide ways to get yours active if this is the case. Maine Coons love to play, so factor in plenty of play sessions every day to give your cat the exercise it needs to keep it trim.

Rosie loves her tunnel; age 2, 14 pounds in weight


If a Maine Coon is left alone or ignored, it can get bored and lethargic. A bored cat often eats more. This leads to weight gain.

Make sure your Maine Coon has distractions when you’re out, such as a view from a window where it might watch birds or passers-by. Invest in some interactive toys. Leave a radio on. Even better, get another cat to keep it company.

Are Maine Coon cats bigger than other domestic cats?

Maine Coon cats are bigger than many domestic cats, but they are not the biggest. They do fall into the same size category as several other breeds.

The six largest domestic cat breeds in no particular order are:

  1. Maine Coon
  2. Ragdoll
  3. Ragamuffin
  4. Norwegian Forest Cat
  5. Siberian Cat
  6. American Bobtail

How big is a Maine Coon cat?

A Maine Coon can be about as big as some dogs such as a Cavalier King Charles Spaniel. The length and height a Maine Coon cat grows to depend heavily on genetics, but its weight can be affected by factors such as whether it is an indoor or outdoor cat, how much it is fed, and how much exercise it gets.

A male Maine Coon can reach a height of between 10 and 16 inches (from shoulders to the ground) and a length of 40 inches from nose to tail.

The female is slightly shorter at about 10 to 14 inches from shoulders to the ground and she can reach the same length as the male. Of course, there will always be some Maine Coon cats that are smaller or larger than these averages.

Above-average Maine Coons can exceed 45 inches in length and weigh over 30 lbs. Some of this length can be made up of 16 inches of tail! Cats of this size are rare and often likely to be overweight.

Though there are reports of a Maine Coon called Omar measuring 47 inches and a Maine Coon called Lewie measuring 48 inches, the current Guinness World Record holder is Ludo.

On October 6, 2015, Ludo was 46.5 inches long. On that date, he was only 3 years old and weighed 34 lbs. He’s probably considerably larger than that by now.

Can You Predict the Size a Maine Coon Cat Will Become?

There is no way to accurately predict the size a full-grown Maine Coon cat will be. To a certain degree, genetics play a role but, just as with humans, there is no guarantee that Maine Coon kittens will be the size of either of their parents.

Depending on dominant genes,  a litter of kittens can all grow to different sizes, some smaller, some similar, and some larger than either of their parents. What is quite likely is that you will end up with a larger-than-average cat.

Why do Maine Coons grow so large?

These cats are nicknamed ‘gentle giants’ and it’s no wonder. They are the largest (and most popular) breed of domestic cat and are well known for their gentle nature and temperament.

Very little is known about their true lineage, so there is no way of really knowing why Maine Coon cats grow as large as they do.  

What is known is that Maine Coons can be extremely large cats and there is a genetic link to their size. There are various beliefs about the Maine Coons lineage.

Some people think they are part raccoon or part bobcat mixed with a domestic cat (which is actually genetically impossible).  The truth is no one really knows the true origin of this beautiful giant breed.

The Maine Coon is the only native American cat. It could be descended from the Norwegian Skogkatt, which may have come over with the Vikings on their travels. 

The Norwegian Skogkatt has many physical traits in common with the Maine Coon so it is quite possible that the Maine Coon is one of its descendants.

A Maine Coons size means it is very well adapted to survive in harsh winter climates. Its large paws help it to walk on snow and long tufts of hair between its toes help to keep its feet warm.

It has extremely furry ears with extra long tufts of fur growing on the inside and on the tips to keep them warm and protected. Its long, bushy tail can be curled around its face to provide extra protection against the cold.

A small red smoke Maine Coon kitten sitting facing the camera.

At what age is a Maine Coon fully grown?

Maine Coons keep growing for longer than any other breed. Most breeds reach their full size at about 2 years of age but some say Maine Coons can keep growing until they are about 4 years old. We’ve never found this, but every cat is different.

Can diet affect a Maine Coons size?

Yes, what it eats can definitely affect the size of a Maine Coon but your primary concern should be feeding your Maine Coon correctly right from the start.

You should never try to increase your cat’s size by giving it too much food as this could result in your cat being heavy only because it is overweight. You don’t want an overweight Maine Coon as this is very likely to lead to poor health and shorten its lifespan.

Ideally, you should feed your Maine Coon twice a day. In my experience, Maine Coons are quite fussy eaters so make sure your cat really likes a particular food before buying it in bulk.

Basic dietary requirements

Just like any other cats, Maine Coons need certain elements in their diet, including:

  • Protein
  • Carbohydrates
  • Fats and Fatty Acids
  • Amino Acids
  • Vitamins and Minerals

You should always buy foods specifically developed for cats as these are developed with the right balance of nutrition for good health. They also make it easier to manage portion control.

There are some foods formulated specifically for Maine Coon cats, but research seems to suggest that these don’t make a significant difference to a Maine Coon’s health. So it’s OK to buy any good quality cat food.


There has been much debate on cat food ingredients over the years. All cat food sold in shops should meet certain standards. When choosing food, consider your own thoughts on the matter, your budget, your cat’s preferences and seek advice from a vet.

Protein is the most important ingredient in a cat’s diet, especially for a large breed like the Maine Coon. Most vets agree that animal proteins such as meat, chicken, and fish are preferable to plant proteins.

So, it is not a good idea to make your cat a vegetarian just because you are.

Where possible, you should choose food that includes real protein sources rather than those that contain “meal” or “by-products.” Many pet owners like to feed their pet a grain or gluten-free diet, believing that these ingredients are bad for a cat’s digestion.

This is totally unnecessary if your pet doesn’t have a diagnosed grain or gluten allergy.

Maine Cooons can be fussy about flavors so you will need to experiment until you find their favorites. And of course, once you’ve established this, you can bet your life they’ll go off that particular variety the day you buy a month’s supply because it was on offer!

Wet versus dry food

Whether you feed your cat wet or dry food is also a matter of preference. Here are some thoughts:

  • Dry foods are easier to prepare than wet foods and allow a cat to use its teeth. Some claim to be formulated to help keep a cat’s teeth clean.
  • Wet foods have a higher moisture content than dry foods. This is important to maintain proper kidney function especially if your cat doesn’t drink a lot of water. It’s worth considering more wet foods for older cats.
  • A mix of wet and dry food might be best to ensure the right dietary balance for your cat.

Food for each life stage

Just like us, Maine Coons require different nutrition at each stage of life. A kitten needs different food than a fully grown cat and a young adult cat’s dietary requirements differ from those of a senior cat. Most food brands treat cats of 7 years plus as seniors.

  • You should feed your Maine Coon kitten a formula designed specifically for kittens. This will be carefully formulated to meet all of its dietary requirements.
  • Because Maine Coon Cats reach maturity later than other breeds, you may want to keep your cat on kitten food longer. Most cats make the switch at around 4 to 5 months of age, but some vets suggest keeping Maine Coons on kitten food up until they are 9 months. You should discuss this with your vet if you aren’t sure when to make the change.
  • Senior cats also have different needs. Many companies make food specially designed for older cats which you might consider, depending on your cat’s health. These are generally lower in energy to prevent your elderly cat from gaining weight in its lethargic later years.

Can its environment affect a Maine Coon’s growth?

Indoor cats

Indoor cats will require less food per day as they generally don’t get as much exercise as outdoor cats. It can be difficult to tell if a Maine Coon is becoming overweight because of all that fur! 

Many companies market food specially for indoor cats, but beware as these foods can contain fillers and lower-quality proteins. There’s plenty more information in Can a Maine Coon be an indoor cat 

Outdoors cats

Outdoor cats are usually more active than indoor cats and therefore are able to eat more without gaining excess weight. Make sure your cat is getting the proper amount of food to maintain a healthy weight for its age and size.

Refer to the food package instructions or check with your vet how much you should be feeding your pet.

Three Maine Coons outside on a climbing frame.
Three of our Maine Coons on their climbing frame

Why are Maine Coons so big? Conclusion

Maine Coons aren’t always so big. But they are certainly not small cats, by any means. The biggest Maine Coons are the exception, not the norm and some are overweight rather than well-built.

If you get a Maine Coon, there is no guarantee that it will be a large cat but it will definitely have a huge personality and many other huge features.

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