Dog years to human years

A dog's first year counts as about 15 human years and the second adds 9. After that, the rate depends on size. Pick an age or a size for the full breakdown.

Dog size

Dog’s age in years

Plus months

Dog age chart by size

Dog's age	Small	Medium	Large	Giant
1 year	15	15	15	15
2 years	24	24	24	24
3 years	28	28	30	32
4 years	32	33	35	37
5 years	36	37	40	42
6 years	40	42	45	49
7 years	44	47	50	56
8 years	48	51	55	64
9 years	52	56	61	71
10 years	56	60	66	78
11 years	60	65	72	86
12 years	64	69	77	93
13 years	68	74	82	101
14 years	72	78	88	108
15 years	76	83	93	115
16 years	80	87	99	123
17 years	84	92	104	–
18 years	88	96	109	–
19 years	92	101	115	–
20 years	96	105	120	–

The chart used here stops at 16 years for giant dogs.

Dog sizes

Small dogs: up to 20 lb (9 kg), such as a Chihuahua or Jack Russell. Senior from about 10.
Medium dogs: 21–50 lb (10–23 kg), such as a Beagle or Cocker Spaniel. Senior from about 7.
Large dogs: 51–90 lb (23–41 kg), such as a Labrador or Golden Retriever. Senior from about 6.
Giant dogs: over 90 lb (41 kg), such as a Great Dane or Mastiff. Senior from about 5.

Puppy ages

In the first year every size counts the same, at about 1.25 human years per month.

Common questions

Do small dogs live longer than big dogs?

Generally, yes. Larger dogs tend to age faster and have shorter lives, which is why the chart gives bigger dogs a higher human age at the same calendar age.

When is a dog considered a senior?

It depends on size. Small dogs are often considered seniors from about 10, medium dogs from about 7, and large or giant dogs from about 5 to 7.

Is the 7 dog years to 1 human year rule accurate?

Not really. It ignores fast early aging and size differences. A dog's first year is closer to 15 human years, and the second adds about 9.