In general, cats live longer than most dogs. An average life span might be 12 to 14 years, with some cats reaching 20 and more. A cat's longevity depends on whether or not it lives indoors or is allowed outdoors (outdoor cats live an average of eight years), genetics, feeding, enviroment, veterinary care and some other factors. The general consensus is that at about age seven a cat can be considered "middle-aged", and at age 10 and beyond - old.

It was once generally thought that one year in the life of the cat was equivalent to seven years of a human life. A new scale of equivalents is now recognized: after the first two years, the cat's life proceeds more slowly in relation to human life and each feline year is approximately four human years.

Use the chart below to determine your cat's age in relation to a human's.

Cat's Age: ...................................Human's Age:
6 months...............................................10 years
8 months...............................................13 years
10 months..............................................14 years
1 year....................................................15 years
18 months..............................................20 years
2 years..................................................24 years
4 years..................................................32 years
6 years..................................................40 years
8 years..................................................48 years
10 years................................................56 years
12 years................................................64 years
14 years................................................72 years
16 years................................................80 years
18 years................................................88 years
20 years...............................................96 years
21 years..............................................100 years