Pet Age Calculator
Free pet age calculator for dogs, cats, rabbits, hamsters, guinea pigs, birds, horses, turtles, ferrets, and fish. Uses breed-specific, size-adjusted formulas with UCSD scientific option for dogs. Shows life stage timeline, health guide, fun stats (heartbeats, naps, meals), and downloadable shareable pet age card.
Who's your companion?
Select your pet to discover their human age
| Pet Age | Human Equivalent |
|---|
| Your Age | Pet Age | Life Stage |
|---|
How to Use
Click on your pet from the 10-species grid: dog, cat, rabbit, hamster, guinea pig, bird, horse, turtle, ferret, or fish.
Type their name, select age in years and months. For dogs, search 150+ breeds to auto-detect size. For cats, choose indoor/outdoor lifestyle.
Results appear instantly: human age, life stage timeline, health tips, fun stats (heartbeats, naps, meals), and a shareable age card.
Download a beautiful pet age card for social media, or add more pets to compare your whole pet family side by side.
The Science Behind Pet Age Calculation
The old "multiply by 7" rule for dogs is a myth. Dogs age much faster in their first two years and then the rate varies by size. Our calculator uses AKC-recommended size-adjusted formulas and optionally the 2019 UCSD epigenetic logarithmic formula published in Cell Systems.
Why Size Matters for Dogs
Small dogs age slower after maturity and can live 14-16 years, while giant breeds age faster and typically live 7-10 years. A 7-year-old Chihuahua is about 44 in human years, while a 7-year-old Great Dane is about 59.
Indoor vs Outdoor Cats
Indoor cats typically live 12-18 years while outdoor cats average 2-5 years. Our calculator adjusts for lifestyle — a feature most competitors don't offer.
100% Private
All calculations happen in your browser. No data is sent anywhere.