How Old Is My Cat in Human Years? CatChannel & Cat Fancy veterinary expert, Arnold Plotnick, DVM, provides some valuable insight and a chart for estimating a cat's age as it compares to a person's age.

"The notion that dogs (and cats) age seven years for every one year is a myth that’s managed to stick around for years. If you think about it, it is not uncommon for some cats to live to be 18 or 19 years old. If they aged seven years for every one year, then an 18 year old cat would be equivalent to a 126 year old person, which is clearly not very likely. In my practice, we have at least 10 cats who are over 20 years old, but there are certainly no 140 year old people. The seven to one rule is just not true.

Cats age faster when they’re younger, but this slows down as they get older. At 6 months of age, a female cat already can reproduce. At 1 year of age, cat bones fully stop growing. This occurs in people at approximately 24 years of age, give or take a few years. So, a 1 year old cat is roughly equivalent to a 24 year old person. From that point on, cats age approximately four years for every one year. While this is certainly not an exact science, the table below should offer a reasonable guideline as to how cats age compared to humans."

Cat Age       Human Age

6 mos                15 years

1 year              24 years

2 years            28 years

3 years            32 years

4 years             36 years

5 years             40 years

6 years             44 years

7 years             48 years

8 years            52 years

9 years              56 years

10 years            60 years

11 years             64 years

12 years            68 years

13 years            72 years

14 years            76 years

15 years            80 years

16 years            84 years

17 years            88 years

18 years            92 years

19 years           96 years

20 years            100 years