Pet Age Calculator (Dog & Cat)
Based on AVMA-recommended formulas. Dog age scales by breed size; cats use a single formula.
How to Use
Dog or cat. Aging speed and average lifespan differ; separate formulas are applied.
Enter years and months. Under 1 year, only months are needed (e.g., 6 months).
Small (≤10 kg), Medium (10–25 kg), Large (25–45 kg), Giant (45 kg+). Larger dogs age faster. Cats use a single formula.
FAQ
Conversion formula?
AVMA-recommended. Dogs: year 1 = 15 human-years, year 2 = 24, then +4–9 per year by size. Cats: year 1 = 15, year 2 = 24, then +4 per year.
Why does breed size matter?
Larger dogs age faster. Small breeds live 13–16 years on average, giants 7–10. A 5-year Chihuahua ≈ 36 human-years; a 5-year Great Dane ≈ 45 human-years. This tool uses 4 size bands.
Size categories?
By adult weight: Small ≤10 kg (Maltese, Poodle, Chihuahua, Shih Tzu), Medium 10–25 kg (Cocker, Beagle, Jindo), Large 25–45 kg (Golden, Labrador, Husky), Giant 45 kg+ (Great Dane, Saint Bernard).
Why a single formula for cats?
Cat size variation (British Shorthair vs. Maine Coon) is much smaller than dog breeds, and aging differences are minor. A single formula is accurate enough.
Life stages?
Dogs: puppy (0–1) / adolescent (1–2) / adult (2–7, or 2–5 for large) / senior (7+ or 5+ for large). Cats: kitten (0–1) / young (1–6) / adult (7–10) / senior (11+).
Why human-equivalent age?
The actual age stays as-is, but human-equivalent makes diet, exercise, and health care decisions intuitive. A 7-year-old large-breed dog is roughly equivalent to a person in their late 50s.
Is my input sent to a server?
No. All computation runs in your browser; inputs are never sent over the network.
