Age & Life

Their years, in perspective.

Compare dog and cat ages with published charts. It’s a life-stage illustration, not a prediction of how long they’ll live.

A little context helps

What the answer means

Choose the right chart

For dogs, select the adult size group from the AKC chart. Cats use the AVMA chart. Both references list yearly values from age 1 through 16.

Months are an approximation

Between listed birthdays, this calculator uses a straight-line estimate between the two neighbouring values and rounds to a whole human year. It is not a separate biological aging model.

Keep the comparison light

A “human age” does not assess health, predict lifespan or set a care schedule. Your pet’s actual age, breed and health history are more useful to a veterinarian.

Why not just multiply by 7? The AKC, citing the AVMA, says dogs do not age at 7 human years per year. In the AKC chart a dog’s first year counts as 15 human years (12 for a giant dog) and two years as 24 (22 for a giant dog). After that, each year adds about 4 human years for a small dog, 4 to 6 for a medium one, and up to 7 to 9 for large and giant dogs. The AVMA’s cat chart starts the same way, then adds 4 a year.

The published age equivalents

Pet age	Small dog	Medium dog	Large dog	Giant dog	Cat
1 year	15	15	15	12	15
2 years	24	24	24	22	24
3 years	28	28	28	31	28
4 years	32	32	32	38	32
5 years	36	36	36	45	36
6 years	40	42	45	49	40
7 years	44	47	50	56	44
8 years	48	51	55	64	48
9 years	52	56	61	71	52
10 years	56	60	66	79	56
11 years	60	65	72	86	60
12 years	64	69	77	93	64
13 years	68	74	82	100	68
14 years	72	78	88	107	72
15 years	76	83	93	114	76
16 years	80	87	99	121	80

Age in human years. AKC size groups: small 20 lb or less; medium 21–50 lb; large 51–100 lb; giant over 100 lb. Weight boundaries are rounded categories: for a dog near one, ask your vet which group fits. The AVMA calls its values approximate calculations.

Guides in this section

Kitten Age ChartHow old is my kitten? Estimate a kitten's age from its weight, teeth and eyes, with a week-by-week chart from the ASPCA and what changes after 8 weeks.

Follow the numbers

Sources for this tool

Checked Oct 17, 2026

American Kennel ClubHow to Calculate Dog Years to Human YearsThe age chart for four adult dog size groups, ages 1–16, and why 7:1 doesn’t hold.American Veterinary Medical AssociationPets age faster than peopleCat-to-human age equivalents for ages 1–16; pet ages are approximate calculations.