To what age can a cat live, and to what human ages do every five years of a cat's life equate?

I believe that 1 human year equates to 5 feline years, therefore the answer would be 25. There are always exceptions to the rule, but most cats live to around 16 years old. The Guinness book of records has some amazing stories of feline longevity though!

Actually the 5 year rule doesn't apply until the cat is older. The first 6 mos of a cat equal about 12 years of a human. Then first year about 4 years, second year about 8 years, and then from year 3 on up equivalent to 3-4 human years - depending on the source. If a cat makes it to 30 - that's about 100 in human life.

You can use this chart 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

http://www.cats.alpha.pl/catsage.htm

Which makes my cats about:
44
38

Neat-o!

My last kitty lived until he was 20 (human years)

...and right now I have a 10 year old & a 31 year old (kitty years)

Sorry guys, but you're going to have to bump up the age equivalent of the first year...

Cats are sexually mature and can get pregnant at as early as 5-6 months, so you have to take that into consideration! (Compare that to the age where humans can get pregnant.) The first year is probably the equivalent to about 20 human years, then it goes down from there.

If I remember right, I believe the average life span of an indoor cat is about 14 years, whereas the average life span of an outdoor cat is 2 years. Just last week we had a 20 year old cat come in for euthanasia, but I'm going to put the most common age for requests to be 14-16.