Cat Age Calculator

Convert your cat’s age to human years with the standard feline chart and see its life stage. Calculates in your browser.

Roughly equivalent human age

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Life stage-

Show the math

Cats grow up quickly and then age steadily. The widely-used feline chart counts the first year as about 15 human years, the second year as 9 more, then 4 human years for every cat year after that:

human = 24 + (years − 2) × 4

So a 1-year-old cat is roughly 15, a 2-year-old about 24, and a 10-year-old around 56.

These are averages, indoor cats often live well into their late teens. Everything is calculated in your browser.

What this does

A cat age calculator converts your cat’s age to human years with the standard feline chart and shows its life stage.

How to use it

  1. Enter your cat’s age.
  2. Read the human-year equivalent.
  3. See the life stage.
  4. Compare year by year.

How it works

The first year counts as ~15 human years, the second adds 9, and each year after adds roughly 4. Many indoor cats live well into their late teens.

first year ≈ 15, second +9, then +4 per year

Understanding your result

The human-age figure mainly tells you your cats life stage, which guides diet, activity, and vet care. The first two years account for most of the ageing, then it settles to about four human years annually, and many indoor cats stay healthy well into their late teens.

Example

A 3-year-old cat is about 28 in human years.

Sources & methodology

Last updated .

Frequently asked questions

How are cat years calculated?

The first year counts as about 15 human years, the second adds 9 more, and every year after that adds roughly 4 human years.

When is a cat a senior?

Cats are generally considered mature from about 7, senior from 11, and geriatric past 15, though many indoor cats live well into their late teens.

Is anything stored?

No. Everything is calculated locally in your browser.