Dog Age Calculator in Human Years

Dog age to human age chart

A 1-year-old dog is about 15 in human years and a 2-year-old about 24, whatever its size. After that, each year adds 4 human years for a small dog and up to 7 for a giant: at 10, a small dog is about 56, a medium dog 64, a large dog 72 and a giant 80.

Dog's age	Human age	Life stage
6 months	8 years	Puppy
1 year	15 years	Adult
2 years	24 years	Adult
3 years	28 years	Adult
4 years	32 years	Adult
5 years	36 years	Adult
6 years	40 years	Adult
7 years	44 years	Adult
8 years	48 years	Adult
9 years	52 years	Adult
10 years	56 years	Senior
11 years	60 years	Senior
12 years	64 years	Senior
13 years	68 years	Senior
14 years	72 years	Senior
15 years	76 years	Senior
16 years	80 years	Senior
17 years	84 years	Senior
18 years	88 years	Senior

Dog's age	Human age	Life stage
6 months	8 years	Puppy
1 year	15 years	Adult
2 years	24 years	Adult
3 years	29 years	Adult
4 years	34 years	Adult
5 years	39 years	Adult
6 years	44 years	Adult
7 years	49 years	Adult
8 years	54 years	Senior
9 years	59 years	Senior
10 years	64 years	Senior
11 years	69 years	Senior
12 years	74 years	Senior
13 years	79 years	Senior
14 years	84 years	Senior
15 years	89 years	Senior
16 years	94 years	Senior

Dog's age	Human age	Life stage
6 months	8 years	Puppy
1 year	15 years	Adult
2 years	24 years	Adult
3 years	30 years	Adult
4 years	36 years	Adult
5 years	42 years	Adult
6 years	48 years	Adult
7 years	54 years	Senior
8 years	60 years	Senior
9 years	66 years	Senior
10 years	72 years	Senior
11 years	78 years	Senior
12 years	84 years	Senior
13 years	90 years	Senior
14 years	96 years	Senior

Dog's age	Human age	Life stage
6 months	8 years	Puppy
1 year	15 years	Adult
2 years	24 years	Adult
3 years	31 years	Adult
4 years	38 years	Adult
5 years	45 years	Adult
6 years	52 years	Senior
7 years	59 years	Senior
8 years	66 years	Senior
9 years	73 years	Senior
10 years	80 years	Senior
11 years	87 years	Senior

The "one pet year equals seven human years" myth

This simple rule is wrong. Dogs and cats become adults in barely one to two years, then age more slowly. One early year of life is worth far more than seven human years, while a year late in life is worth less.

How age in human years is calculated

The first year is worth about 15 human years, the second adds 9 (24 by age two), then each following year adds a few human years. For dogs, that pace depends on size: large breeds age faster than small ones.

The main life stages

Understanding your pet's life stage helps you adapt its diet, activity and health care.

Puppy

Fast growth: vaccines, deworming, socialisation and identification (microchip) are the priorities of the first months.

Adult

Prime years: one vet visit a year, a suitable diet and regular activity are enough to keep them healthy.

Senior

Watch weight, teeth and joints. Two vet visits a year help catch health issues early.

An estimate, not a diagnosis

This calculator gives a ballpark figure. Every animal ages at its own pace, and only a vet can properly assess its health.

Our sources

Main method (first year ≈ 15 human years, then progression by size): the American Kennel Club's conversion reference. akc.org
Cat life stages: the AAHA / AAFP feline life-stage guidelines. catvets.com
DNA method (dog): Wang et al., "Quantitative Translation of Dog-to-Human Aging by Conserved Remodeling of the DNA Methylome", Cell Systems, 2020 (formula 16 × ln(age) + 31, derived from Labradors). cell.com

Going further

Welcoming an animal well also means planning ahead and being ready to react.

A cat's ageThe other curve, tuned to its species.How much does a pet cost?The real budget, from adoption to a whole life.Lost-pet posterCreate a print-ready search notice.

FAQ - Frequently asked questions

Why does my dog's size change the result?

The bigger the dog, the faster it ages. A small dog can live 15 years or more, while a giant breed often reaches its senior years by age 6 or 7. That's why we ask for size.

When is my dog considered senior?

It depends on size: around 10 for a small dog, but as early as 6 or 7 for a large or giant one. From then on, more regular vet check-ups are recommended.

Does this replace the vet?

No. It's an estimate to help you understand your dog's life stage. Only a vet can properly assess its health and true age.

Your dog's age in human years

Calculate your pet's age