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Biological Age Calculator

Biological Age Calculator

Your birthday tells you how many years have passed. It does not tell you how well your body is holding up. Estimate your biological age from a selfie, a short lifestyle questionnaire, or both.

Free to use. No account needed. Photographs are never stored.

What is biological age?

Chronological age is simply the number of years since you were born. It moves at the same rate for everyone and nothing you do will change it.

Biological age is a different idea. It is an estimate of how old your body appears to be, based on signals associated with health and ageing. Two people born on the same day can look and function very differently at fifty, because sleep, movement, stress, smoking, alcohol and a great deal of luck all leave traces.

This calculator gives you a readable estimate of that idea. It is a wellness estimate rather than a clinical measurement, and it is designed to be honest about the difference.

Laboratories measure biological age in other ways, most notably with epigenetic clocks that read chemical marks on your DNA from a blood or saliva sample. Those tests are the most researched approach, and also the slowest and most expensive. This calculator takes the opposite trade: it uses information you already have, so you get an answer in seconds, and it tells you plainly where that answer is broad.

Biological age vs chronological age

The two are easy to confuse, because both are reported in years. They answer different questions.

Aspect Chronological age Biological age
What it measures Time elapsed since you were born. How old your body appears to be.
How it is worked out Your date of birth. Nothing else is needed. Estimated from health, appearance and lifestyle signals.
Can it change No. It only ever moves in one direction, at one rate. Yes. It can sit above or below your chronological age.
Is it the same for everyone born on the same day Always. Rarely.
What it is useful for Records, eligibility and birthdays. Deciding which habits are worth your attention.

How to calculate your biological age

Three steps, no account, and nothing to install.

  1. Step 1

    Tell us your age

    Your chronological age is the baseline every estimate is measured against. It is the only required input.

  2. Step 2

    Choose what to share

    A selfie, a short questionnaire, or both. You decide how much to provide, and you can stop at any point.

  3. Step 3

    See your estimate

    You receive an estimated biological age with a range, the factors that shaped it, and practical suggestions.

Three ways to estimate

Most calculators make you complete a long form before showing you anything. This one lets you decide how much to share. Every path produces a result.

Why biological age matters

Common questions

What is biological age?
Chronological age counts the years since you were born. Biological age is an estimate of how old your body appears to be, based on signals associated with health and ageing. Two people born on the same day can differ, because lifestyle and environment shape how the body ages.
What is the difference between biological age and chronological age?
Chronological age is a fact. It is fixed, it is identical for everyone born on the same day, and nothing changes it. Biological age is an estimate. It varies between people of the same chronological age and it can move in either direction. That difference is the whole point of the comparison: your chronological age tells you how long you have been here, while a biological age estimate is a prompt to think about how you have been living.
How is biological age calculated?
You always provide your chronological age. You may then add a selfie, a short lifestyle questionnaire covering sleep, exercise, smoking, alcohol, stress and body measurements, or both. Each answer is compared with what is typical for an adult, and the differences are weighted according to published research and applied to the age you entered. The engine is deterministic, so identical inputs always produce an identical result, and no language model decides your number.
Is my photo stored?
No. A photograph is processed only to produce your estimate and is discarded immediately afterwards. There is no database, no account and no history of your results. The Privacy Policy explains this in full.

Read all frequently asked questions

What is your biological age?

It takes about thirty seconds to find out, and you never have to upload a photograph if you would rather not.

Start your estimate

Curious how the estimate is put together? Read about the project.