The quick chart
- 1 dog year = about 15 human years (all sizes)
- 2 dog years = about 24 human years (all sizes)
- After that, each year adds about: 4 human years (small dogs), 5 (medium), 6 (large) or 7 (giant)
So a 7-year-old small dog is about 44 in human years, while a 7-year-old giant breed is about 59. Try any age in our dog age calculator.
Life stages and what they mean
- Puppy: vaccines, training, socializing and lots of food for growth
- Young adult and adult: yearly checkups, dental care, a healthy weight and plenty of exercise
- Senior: more frequent vet visits, joint support and diet changes, depending on your vet's advice
Why big dogs age faster
Scientists are still studying why, but larger breeds tend to have shorter lifespans and reach their senior years sooner. That's why the chart adds more human years per dog year for bigger dogs.
Never lose track of vaccines and vet visits.
Our printable pet health record keeps vaccines, meds, weight and vet visits together. Instant download.
Try the numbers for your pet
Our free dog age calculator works it out in seconds. No sign-up.
Open the calculatorQuestions people ask
How old is a 5-year-old dog in human years?
About 36 for a small dog, 39 for a medium dog, 42 for a large dog and 45 for a giant breed, using the common size-based chart.
Why is the dog years times 7 rule wrong?
Dogs mature very quickly in their first two years and then age more slowly, and the pace depends on size. A flat 7-to-1 ratio ignores both.
At what age is a dog a senior?
Giant breeds can be seniors by 5 or 6, large dogs around 7 or 8, and small dogs often around 10 or later.
Save this for later.
Pin it to your pet board so it's there when you need it.
The Paw Plan shares general information, not veterinary advice. Every pet is different, so check with your vet about your pet's health, diet and care.
More guides you'll like
How much should I feed my dog?
The right amount depends on your dog's weight, age, activity and food. Here's a simple way to find a starting point and adjust.
Read the guide →Cat years to human years: chart and life stages
Cats grow up in a hurry, then age about four human years for every cat year. Here's the chart.
Read the guide →How to keep track of your pet's vaccines and vet records
Boarding, groomers, daycare and new vets all ask for vaccine records. A simple system saves a lot of scrambling.
Read the guide →One easy pet-care tip a week.
Short, practical and friendly. Join free and get our printable pet emergency contact card right away.
