Dog Age Calculator

Accurately convert your dog's age to human years. Uses updated veterinary formulas based on breed size for more accurate results than the 7x rule.

Dog Age (Years)

Additional Months

Breed Size

e.g. Beagle, Bulldog, Cocker Spaniel, Border Collie

Human Age Equivalent

39years

AdultPrime years, annual vet checkups, maintain healthy weight

Life Expectancy Progress5.0 / 10-13 years

Birth43% of estimated lifespanAvg. 12 yrs

Life Stages

Puppy

Dog: 0-6 months | Human: 0-10 years

Junior

Dog: 6-12 months | Human: 10-15 years

AdultCurrent

Dog: 1-7 years | Human: 15-44 years

Mature

Dog: 7-10 years | Human: 44-56 years

Senior

Dog: 10-13 years | Human: 56-74 years

Geriatric

Dog: 13+ years | Human: 74+ years

Age by Breed Size (at 5.0 dog years)

Small (Under 20 lbs)

36.0 yrs

Life expectancy: 12-16 years

Medium (20-50 lbs)Selected

39.0 yrs

Life expectancy: 10-13 years

Large (50-100 lbs)

42.0 yrs

Life expectancy: 8-11 years

Giant (100+ lbs)

42.0 yrs

Life expectancy: 6-10 years

Larger breeds age faster than smaller breeds after maturity. A 5-year-old Great Dane is significantly older in human years than a 5-year-old Chihuahua.

Age Conversion Chart (Medium Dogs)

Dog Age	Human Age	Life Stage
1 yr	15	Adult
2 yr	24	Adult
3 yr	29	Adult
4 yr	34	Adult
5 yrNow	39	Adult
6 yr	44	Adult
7 yr	49	Mature
8 yr	54	Mature
9 yr	59	Mature
10 yr	64	Senior
11 yr	69	Senior
12 yr	74	Senior
13 yr	79	Geriatric
14 yr	84	Geriatric
15 yr	89	Geriatric
16 yr	94	Geriatric

Health Milestones & Vet Recommendations

✓

First vaccinations (DHLPP)

At age 2 months

✓

Second round of vaccinations

At age 4 months

✓

Spay/neuter consideration

At age 6 months

✓

Switch to adult food; annual wellness exam

At age 1 years

✓

Dental cleaning recommended

At age 3 years

▶

Senior bloodwork panel; biannual vet visits

At age 7 years

Upcoming

○

Senior diet transition; joint supplement consideration

At age 10 years

○

Quarterly vet visits advised

At age 12 years

Care Tips for the Adult Stage

●Annual vet checkups

●30-60 min daily exercise

●Monitor weight

Disclaimer: This calculator uses updated veterinary aging formulas that account for breed size differences. The traditional “multiply by 7” rule is inaccurate — dogs age more rapidly in their first two years, and larger breeds age faster than smaller breeds. Individual aging varies based on genetics, diet, exercise, and healthcare. Consult your veterinarian for personalized health guidance.

How to Use Dog Age Calculator

1Enter your dog's age in years and months
2Select your dog's breed size
3View the equivalent human age
4Check the life stage and health tips

Frequently Asked Questions

Is 1 dog year really 7 human years?▾

No, the 7:1 ratio is a myth. Dogs age much faster in their first two years (about 15 human years in the first year), then slow down. Breed size significantly affects the aging rate.

How long do dogs live on average?▾

Small breeds typically live 12-16 years, medium breeds 10-14 years, large breeds 8-12 years, and giant breeds 6-10 years.

At what age is a dog considered a senior?▾

It depends on size: small dogs become senior around 10-12 years, medium dogs at 8-10, large dogs at 6-8, and giant breeds at 5-6 years.

About Dog Age Calculator

Accurately convert your dog's age to human years. Uses updated veterinary formulas based on breed size for more accurate results than the 7x rule.

NexTool's Dog Age Calculator is completely free to use with no sign-up required. Your data is processed directly in your browser and never sent to our servers, ensuring complete privacy and instant results.