Free tool

Biological age calculator

This biological age calculator has two free tools: a healthy ageing score out of 100 from 8 questions, and an estimate of your biological age from 9 blood test results, using the published PhenoAge formula.

  • Based on published research
  • Free, no sign-up
  • Your answers stay on your device
1 Exercise

Minutes a week of moderate or vigorous activity. Brisk walking, cycling, swimming and sport all count.

2 Smoking and vaping
3 Sleep

Average hours of sleep a night.

4 Diet

Tick everything that is true for a typical week.

5 Height and weight

From a health check or blood test

Leave these as "I don't know" if you have not had them measured. Your score will use the measures you have.

6 Cholesterol

Non-HDL cholesterol is on most UK blood test results. If yours only shows total and HDL cholesterol, enter those instead.

7 Blood sugar
8 Blood pressure

Your answers stay on your device. Nothing is sent to us or stored on our servers. Your last result is saved in this browser so you can compare next time.

Our email list

Get new research guides by email

New guides, research summaries and offers. New customers get 10% off their first order with code WELCOME10. Unsubscribe any time.

How this biological age calculator works

There are two tools on this page, because there are two honest ways to look at how you are ageing.

The healthy ageing score

This uses Life's Essential 8, the scoring system the American Heart Association published in 2022 to measure cardiovascular health. It scores eight things from 0 to 100: exercise, smoking, sleep, diet, BMI, cholesterol, blood sugar and blood pressure. Your overall score is the average. A score of 80 or more is high, 50 to 79 is moderate, and under 50 is low.

We use it because it is published, checkable and linked to how people age. In a study of 11,729 US adults, people with higher Life's Essential 8 scores had a lower biological age on blood-based measures, including PhenoAge (Zhang and colleagues, 2023). The average US adult scores about 65.

One change from the official version: the AHA scores diet with a 16-question questionnaire. We use a shorter 8-question version based on the same eating pattern, scored on the same scale, so treat your diet score as a guide.

The PhenoAge calculator: biological age from a blood test

This uses PhenoAge, a formula published by Morgan Levine and colleagues in 2018. It combines your age with nine blood results: albumin, creatinine, glucose, CRP, white blood cell count, lymphocytes, MCV, RDW and alkaline phosphatase. The formula was built from the blood tests and mortality records of US adults, and it is one of the most widely used biological age measures in research.

The result is an estimate. A single blood test varies from day to day, so a difference of a year or two either way does not mean much. Retesting at the same time of day, under the same conditions, every few months gives you a much better picture.

What is biological age?

Your chronological age is how long you have been alive. Your biological age is an estimate of how old your body looks on tests that change as people age, such as blood markers or patterns of DNA methylation. Two people born on the same day can have quite different results.

No questionnaire can measure biological age directly. That is why the healthy ageing score gives you a score out of 100 rather than an age, and why the age estimate on this page needs real blood results.

Sources

  • Lloyd-Jones and colleagues. Life's Essential 8: updating and enhancing the American Heart Association's construct of cardiovascular health. Circulation, 2022. PubMed 35766027
  • Lloyd-Jones and colleagues. Status of cardiovascular health in US adults and children using Life's Essential 8. Circulation, 2022. PubMed 35766033
  • Zhang and colleagues. Association between Life's Essential 8 and biological ageing among US adults. Journal of Translational Medicine, 2023. PubMed 37710295
  • Levine and colleagues. An epigenetic biomarker of aging for lifespan and healthspan. Aging, 2018. PubMed 29676998

This calculator is for general interest and is not medical advice. If any of your results are outside your lab's normal range, or you are worried about your health, speak to your GP.

Questions about the biological age calculator

Can an online quiz tell me my biological age?

No. Biological age is estimated from blood tests or DNA tests, not from a questionnaire. That is why the healthy ageing score gives you a score out of 100, and the biological age estimate on this page needs real blood results.

Which blood tests do I need for the PhenoAge calculator?

Nine results: albumin, creatinine, glucose, CRP, white blood cell count, lymphocytes, MCV, RDW and alkaline phosphatase, plus your age. Most private advanced or longevity blood tests include all nine. NHS tests often leave out RDW or CRP.

What is a good healthy ageing score?

80 to 100 is high, 50 to 79 is moderate, and under 50 is low. These are the American Heart Association's bands for Life's Essential 8. The average US adult scores about 65.

How often should I retest?

Every 3 to 6 months is enough to see real change. For the blood test version, test at the same time of day and under the same conditions each time, and avoid testing during an illness, which raises CRP and white blood cells.

Do you store my answers?

No. The calculator runs in your browser and nothing is sent to us. Your last result is saved in your browser only, so you can compare it next time.