Aging Pet Care
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How old am I in dog years?

Enter your own age to see how old a dog or cat would be at the same stage of life. It is the pet age calculator run backwards.

I am40in human years. How old is that for a?

40 in human years is about the same stage of life as a dog of

5½ years

A dog gets to 15 in human terms in its first year and to about 24 in its second. After that each year counts for 4 to 6 of ours, depending on size.

Go the other way: my pet's age →

More on this age: 40 in dog years

The same human age for each size of dog
smallmediumlargegiant
6 years5½ years5 years4½ years

This tool organizes what you have noticed. It can't examine your pet, and its result is not a diagnosis or veterinary advice. Take what it shows to your vet; if your pet is in distress, go to an emergency clinic now. Full disclaimer

How it is worked out

The old rule of seven dog years to one human year is wrong in both directions. Dogs and cats race through childhood, reaching the equivalent of about 15 in their first year and the mid-twenties in their second, then age more slowly.

This converter uses the same curve as our age calculator and turns it around. After the first two years, a small dog adds about four human years for every year it lives, a medium dog four and a half, a large dog five and a giant dog six. Cats add about four.

So a 40-year-old person is at about the same point in life as a five-year-old large dog or a six-year-old small one. It is a way of picturing life stage, not a measure of health: for that, your pet's own vet is the guide.

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