For their size, cats live quite a long time. Generally an animal's longevity is proportional to its size (with the exception of tortoises, man and a few other animals).
A tiny mouse has a short lifespan, a rabbit somewhat longer and a dog between 7 and 20 years depending on its breed or size, its activity, or both. Cats aren't much bigger than rabbits, but whereas the rabbit may live about 8 years a cat will live on average about 12–14 years, and it's not unusual for cats to reach their late teens or even their early 20s.
There are 6 life stages for cats:
- Kitten – 0-6 months
a period when the young cat is growing rapidly and is usually not quite sexually mature
- Junior – 6 months-2 years
during this time the cat reaches full size and learns about life and how to survive it
- Prime – 3-6 years
the cat is mature physically and behaviourally, and is still usually healthy and active, looking sleek and shiny and making the best of life
- Mature – 7-10 years
the cat is what we call 'Mature', equivalent to humans in their mid-40s to mid-50s
- Senior - 11-14 years
takes the cat up to the equivalent of about 70 human years
- Geriatric - 15 years and over
many cats do reach this stage, some not showing any signs of being geriatric at all!
The table below shows all of the stages and also the equivalent human age. What these stages let us do is to appreciate how old the cat is inside, since, as has been pointed out, this is often not very obvious from the outside, as cats seldom go grey or show outward signs of pain or illnesses such as arthritis.