Q: My family and I have been speculating about how cats age. Can you please clear this up for us, as we are not sure? Do cats age in the same manner as dogs? For example, our cat, Bob, is 2 years old. Does that mean that he is 14 years old in cat years?
A: 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 months 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