When will my cat match my age?

Select cat, then enter both birth dates. The calculator estimates the day your cat reaches the same human age as yours - the shared-age day - and shows the time left.

On what date will my pet match my age?

That's the shared-age day. With both birth dates, the tool calculates when your pet reaches the same human age as yours, then lets you add it to your calendar.

How do I calculate the date my pet will match my age?

Pick the species (and dog size), enter both birth dates, then run the calculator. You get the crossover date, a countdown, and an export to Google, Outlook, or Apple Calendar.

What is the shared-age day?

Also called a shared-age birthday: it's the date your pet reaches the same human age as yours. After that, their equivalent age usually overtakes yours because they age faster.

Is "one pet year = seven human years" true?

No. It's an oversimplified average. Cats and dogs grow very fast in the first two years, then aging slows. For dogs, size matters too.

Do cats and dogs follow the same curve?

They're similar early on, then diverge by dog size. Small dogs generally age more slowly than large or giant dogs after the first two years.

Pet age calculator: when will they match your age?

Discover your cat or dog's human age and the exact date they'll match yours. Then add this unique birthday to your calendar and follow the countdown.

When will my cat or dog match my age?

Looking for when your dog will match your age? This calculator finds the exact date - also called the shared-age day or shared-age birthday - when your cat or dog reaches the same human age as yours.

Enter both birth dates (and dog size if needed). You get today's human-equivalent age, the crossover date, a countdown, and you can add the event to your calendar. That's the difference from a basic converter: here you also get the date your ages meet.

Calculate the date your pet will match your age

Estimate the shared-age birthday: when your cat or dog reaches the same human age as yours.

Choose the species
Select cat or dog. For a dog, also choose the size (small, medium, large, or giant).
Enter both birth dates
Add your date of birth and your pet's. The pet's name is optional.
Read the shared-age birthday
The calculator shows the date your ages meet, the countdown, and today's human-equivalent age.
Add the event to your calendar
Save the shared-age birthday to Google Calendar, Outlook, or Apple Calendar so you don't miss it.

How we convert pet age to human years

Our calculator uses popular species- and size-based equivalences. They remain approximations - useful to place life stages and find your shared-age day (when your pet will match your age), not medical advice.

In practice: year 1 is about 15 human years (12 for a giant dog), year 2 often reaches about 24 (22 for giants), then each later year adds 4 to 7 human years depending on size.

Sources: AKCUC Davis Veterinary MedicineWikipedia

How to read this pet-to-human age equivalence chart

Converting a cat or dog's age into human years helps you place life stages: growth, adulthood, then senior years. A 1-year-old cat is already like a young adult, while dogs age faster or slower depending on size.

The chart below converts calendar age (from 1 to 16 years) into approximate human years for cats and four dog sizes. Use it as a quick reference, then the calculator above for a personalized estimate.

Age equivalence chart

Animal calendar age converted to human years, by species and size.

Approximate values based on popular formulas.
Animal age	Cat	Dog
Animal age	Cat	Small	Medium	Large	Giant
1 year	15 years	15 years	15 years	15 years	12 years
2 years	24 years	24 years	24 years	24 years	22 years
3 years	28 years	28 years	29 years	30 years	29 years
4 years	32 years	32 years	34 years	36 years	36 years
5 years	36 years	36 years	39 years	42 years	43 years
6 years	40 years	40 years	44 years	48 years	50 years
7 years	44 years	44 years	49 years	54 years	57 years
8 years	48 years	48 years	54 years	60 years	64 years
9 years	52 years	52 years	59 years	66 years	71 years
10 years	56 years	56 years	64 years	72 years	78 years
11 years	60 years	60 years	69 years	78 years	85 years
12 years	64 years	64 years	74 years	84 years	92 years
13 years	68 years	68 years	79 years	90 years	99 years
14 years	72 years	72 years	84 years	96 years	106 years
15 years	76 years	76 years	89 years	102 years	113 years
16 years	80 years	80 years	94 years	108 years	120 years

Why cat and dog human-age equivalents aren't linear

Popular formulas speed up the early years then slow down. A kitten or puppy "gains" many human years in year one, then progresses more gently. For dogs, a giant size ages faster than a small breed.

These conversions remain approximations, not veterinary diagnoses. They help you understand relative age, anticipate needs, and spot the shared-age day - when your pet will match your age.

Frequently asked questions

Select dog, choose their size, then enter both birth dates. The tool estimates the shared-age day: when your dog reaches the same human age as yours, plus a countdown.