Dog years
99 in dog years
If you are 99, you are at about the same stage of life as a dog of 14½ years to 21 years, depending on the dog's size. For a cat it is about 20½ years.
99 human years, for a medium dog
18½ years
A dog that age is a senior. Size changes the answer because big dogs age faster.
Try another age →| Pet | Same stage of life as 99 |
|---|---|
| Small, under 20 lb dog | 21 years |
| Medium, 20–50 lb dog | 18½ years |
| Large, 50–90 lb dog | 17 years |
| Giant, over 90 lb dog | 14½ years |
| Cat | 20½ years |
Why it is not 99 divided by 7
The seven-year rule would put 99 human years at a dog of about 14 years. It is a tidy sum and it is wrong, because dogs do not age at a steady rate. A dog reaches the equivalent of about 15 in its first year and about 24 in its second, then adds four to six human years for each year after that.
The bigger the dog, the faster that later stretch goes, which is why the table gives a different answer for each size. Cats follow a similar curve: about 15, then 25, then four human years a year.
These are averages that describe a stage of life, not a health check. To go the other way, from your pet's age to human years by breed, use the pet age calculator.
Other ages
In human years.