Cat Age Calculator

By the CalcMundi team · Updated October 22, 2026 · Formulas checked against standard financial math

Enter your cat’s age to see how old it would be as a person and which life stage it is in.

How we calculate

Year 1: about 15 human years.
Year 2: add 9, for 24.
After that: add 4 human years per year.

Example

A 6-year-old cat is about 40 in human years: 24 + 4 × 4.

Cat life stages

Kitten: up to 1 year.
Young adult: 1 to 6 years.
Mature adult: 7 to 10 years.
Senior: over 10 years.

Indoor cats tend to live longer, often past 15.

Frequently asked questions

When is a cat a senior?

From about 10. Checkups every 6 months help catch kidney, thyroid and dental problems early.

What if I don’t know my cat’s age?

A vet can estimate it from the teeth, eyes and coat. Use that estimate here.

Add this calculator to your website

Free for blogs, real estate agents, brokers and any site. Paste this code where you want the calculator to appear. It adjusts its height on its own.

<iframe src="https://calcmundi.com/embed/cat-age-calculator/" title="Cat Age Calculator" loading="lazy" style="width:100%;max-width:680px;height:640px;border:0"></iframe><script>addEventListener("message",function(e){if(e.origin==="https://calcmundi.com"&&e.data&&e.data.cmH)document.querySelectorAll("iframe[src^='https://calcmundi.com/embed']").forEach(function(f){if(f.contentWindow===e.source)f.style.height=e.data.cmH+"px"})})</script><p style="font:13px sans-serif">Calculator by <a href="https://calcmundi.com/cat-age-calculator/">CalcMundi</a></p>

Results are estimates for information only and are not financial, legal or medical advice. Rates, taxes and fees vary — confirm with a professional or your lender.