Calculate your cat’s human-age estimate

Use decimals for younger cats. Example: 0.5 for roughly six months.

How to interpret the number

  • Use it to think about life stage, not as a literal medical conversion.
  • Watch for changes in appetite, grooming, toileting and sleep as cats move into mature and senior phases.
  • Indoor-only cats and outdoor cats may face different risks even at the same age.

When to book the vet

Weight loss, reduced grooming, new house-soiling, hiding, mobility changes or a sudden drop in appetite should not be written off as “just old age”.

Cat age FAQs

Is one cat year really seven human years?
No. International Cat Care and Purina both describe a faster first two years followed by roughly four human years for each later cat year. The old seven-times rule is too blunt. Sources: International Cat Care, “How to tell your cat’s age in human years”; Purina UK cat years guidance
When is a cat considered senior?
Cats Protection and PDSA both place the senior stage at around 11 years old. By 15, many cats are considered super senior or geriatric and benefit from closer monitoring. Sources: Cats Protection, “Elderly Cats”; PDSA, “The best diet for your cat”
Do cats age by breed size the way dogs do?
Not to the same degree. Cat age guidance is usually more consistent across breeds, which is one reason feline calculators can stay simpler than canine ones. Source: International Cat Care, “Cat life stages”
Do indoor and outdoor cats have different ageing risks?
Yes. Cats Protection and International Cat Care both highlight that indoor and outdoor lifestyles carry different welfare risks, so environment matters when you interpret age and care needs. Sources: Cats Protection, indoor cats guidance; International Cat Care, indoor vs outdoor access
What should I watch for in an older cat?
Changes in weight, grooming, mobility, behaviour or litter tray habits deserve attention. Older cats often hide illness, so subtle changes matter. Sources: Cats Protection elderly cats guide; PDSA senior pet feeding guide
Are cat-age conversions exact?
No. They are useful comparisons for life stage and care planning, but they do not replace an actual assessment of the cat in front of you. Sources: International Cat Care age article; Purina UK cat years article