Pet Age Converter

How to use

Select cat or dog; for dogs, choose size.
Enter the pet's actual age in years.
Submit to see the human-equivalent age and life stage.

How the calculation works

Veterinary convention: Year 1 = 15 human years, Year 2 = 24 human years total, then per-year increments: cat +4/yr, dog +4 (small) / +5 (medium) / +6 (large) / +7 (giant). Source: AAHA Life Stage Guidelines.

FAQ

Why isn't 1 year = 7 human years?

That old rule is too rough. Pets grow from newborn to sexual maturity in their first year — much faster than a human child — so veterinarians use a step function rather than a linear ratio.

When do dogs enter senior age?

Depends on size. Small dogs are typically senior around 8–10 years; large and giant breeds start senior around 5–7 years.

When do cats get old?

Cats start senior around 7 (≈ human 40s), move into senior at 11, and 15+ is often considered geriatric. Consider more frequent kidney, thyroid and dental checks.

Why do different converters give slightly different results?

Different organizations (AAHA, AVMA, individual clinics) use slightly different increments, especially for large dogs. The result is a rough guide.

References

AAHA Life Stage Guidelines (https://www.aaha.org/publications/life-stage-guidelines/)
AVMA pet-age conversion references

How to use

How the calculation works

FAQ

References

Related tools