Free calculator
Dog Age Calculator
How old is your dog in human years? Enter their age and size to see two popular conversions and their current life stage.
- Instant result
- No sign-up
- Free
Your result appears here
Fill in your puppy’s details and the answer updates instantly.
Your dog is about
0
in human years
0
classic rule (15 + 9 + size)
n/a
epigenetic formula
Life stage:
General information only, not veterinary advice. Always follow your own vet.
Step by step
How to use the Dog Age Calculator
- 1Enter your dog’s age in years and months.
- 2Choose their adult size.
- 3Read the human-year equivalent and life stage.
- 4Use the life stage to plan vet checks, diet and exercise.
Why use it
Benefits
- Two popular methods in one place
- Life-stage guidance for vet checks
- Size-aware, because large dogs age faster
- Useful for puppies and seniors alike
How dog years are calculated
The old “multiply by 7” rule is too simple. Dogs mature very quickly in their first two years, then age more slowly, and larger breeds age faster than smaller ones.
- Classic rule: the first year equals about 15 human years, the second adds about 9, and each year after adds 4 to 7 depending on size.
- Epigenetic formula: a 2019 study of Labrador retrievers produced the equation human age = 16 × ln(dog age) + 31, based on changes in DNA methylation. It applies from about one year old.
The headline number averages both once your dog is a year old. Under a year, only the classic rule is used.
Free printables
Checklists that go with this tool
HealthPuppy First Vet Visit Checklist
The first vet visit is a chance to start vaccines and parasite prevention. Bring paperwork and a list of questions.
HealthPuppy Vaccination Schedule Checklist
Vaccines protect your puppy from serious diseases. This checklist shows the typical timeline so you can track appointments. Schedules vary by country, region and vet, so always confirm your own plan with your veterinarian.
Before you bring puppy homeNew Puppy Checklist
Bringing a puppy home is exciting and a little overwhelming. This printable new puppy checklist walks you through what to buy, what to prepare and what to book before your puppy arrives, so nothing gets missed.
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Free date calculator
When is the next vet visit?
Enter your puppy's birthday or the day you brought them home and get a dated schedule of vaccines, vet visits and training milestones, ready to print.
Answers
Frequently asked questions
How do I calculate my dog’s age in human years?
Count about 15 years for the first year, 9 for the second, then 4 to 7 for each year after depending on size. Our calculator also compares this with a newer epigenetic formula.
Is one dog year really seven human years?
No. Dogs age much faster in the first two years and the pace depends on size. A one-year-old dog is closer to a 15-year-old human.
When is a dog considered a senior?
Roughly 10 years for small dogs, 8 to 9 for medium, and 6 to 7 for large and giant breeds. Your vet may suggest more frequent checks from then on.
At what age is a dog no longer a puppy?
Most dogs reach adulthood between 12 and 24 months. Small breeds mature sooner, while large and giant breeds can take two years or more.
Is the Dog Age Calculator free to use?
Yes. The Dog Age Calculator is completely free, needs no sign-up and works on phones, tablets and computers.
Can I rely on the Dog Age Calculator instead of my vet?
No. It gives a general starting point based on published guidance. Every puppy is different, so always follow your own vet’s advice.
Support & sponsorship
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