Free Biological Age Calculator
Find out how old your body really functions. Get a quick lifestyle estimate in a minute, or use your blood test results for a more objective number.
Disclaimer: For information only. This tool is not medical advice. Talk to a doctor about your results or health concerns.
What is a free biological age calculator?
Your chronological age is simply the number of years since you were born. Your biological age is an estimate of how well your body is functioning compared with the average person of your age. Two people who are both 45 can have very different biological ages, depending on sleep, activity, diet, smoking, stress and underlying health.
This free biological age calculator gives you two ways to find out. The lifestyle estimate takes about a minute and needs no lab results. The blood test mode uses a published research formula and works best if you have recent results to hand. Both run in your browser, and your answers are never sent to a server.
How the lifestyle estimate works
The lifestyle mode starts with your actual age and adds or subtracts years for eight factors: sleep, exercise, diet, stress, smoking, alcohol, body mass index and social connection. Sleep and BMI are scored as U-shaped, because both too little and too much are linked to poorer outcomes. The adjustments are simplified, rounded estimates informed by research on mortality risk. They are not a clinical measurement, so your result is shown with a range of about three years.
| Factor | Best case | Worst case |
|---|---|---|
|
Sleep |
−1.5 years (7–8 h) |
+3 years (under 5 h) |
|
Exercise |
−3 years (5–6 days) |
+3 years (none) |
|
Diet |
−2 years |
+3 years |
|
Stress |
−1 year |
+4 years |
|
Smoking |
−1 year (never) |
+5 years (current) |
|
Body mass index |
−1 year (18.5–24.9) |
+3.5 years (35 or above) |
|
Social connection |
−1.5 years |
+2.5 years |
Biological age calculator blood test: the PhenoAge formula
If you want a biological age calculator blood test option, switch to the second tab. It uses PhenoAge, which combines your age with nine routine markers: albumin, creatinine, glucose, C-reactive protein, lymphocyte percentage, mean cell volume, red cell distribution width, alkaline phosphatase and white blood cell count. These appear on most standard blood panels and full blood counts.
Enter the values exactly as they appear on your report. Results can shift if you were ill or had an infection recently, because markers such as C-reactive protein rise temporarily.
Yale, NHS, apps and face scans compared
People search for biological age tools in many ways. Here is how the most common ones differ from this page.
Biological age calculator Yale
Most people searching for this want PhenoAge. It was published in 2018 by Morgan Levine and colleagues, at the time at the Yale School of Medicine. This website is independent and is not affiliated with Yale.
Biological age calculator NHS
As far as we know, the NHS does not publish a tool by this name. It offers the Heart Age Test and the NHS Health Check for adults in England aged 40 to 74, which are better starting points for a clinical view.
Biological age calculator app
You do not need to download anything here. This page works in any modern browser and keeps your answers on your device. Apps can help you track results over time, but check what data they collect.
Biological age calculator face
Face tools estimate age from a selfie. Results change with lighting, angle, skin tone and make-up, and they are not validated as measures of internal health. This calculator does not use photos.
What makes the best free biological age calculator?
When you compare the best free biological age calculator options, look past the headline number and check these things:
- A clear method. The tool should tell you which factors it uses and roughly how they are weighted.
- No online tool replaces a clinical assessment. Be wary of any calculator that promises an exact biological age from a few clicks.
- The best biological age calculator for your health data is one that processes it on your device.
- A good result shows what moved your number, not just the number itself.
What makes the best free biological age calculator?
The same few habits come up repeatedly in the research: stop smoking, move most days of the week, sleep around seven to eight hours, eat mostly whole foods, keep alcohol modest, maintain a healthy weight and stay connected to other people. Change one habit at a time, then recalculate in three to six months to see your trend.
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Frequently asked questions
The blood test mode implements a published research formula, so it is more objective than the lifestyle mode. The lifestyle mode is a rough estimate. Neither is a diagnosis or a substitute for medical advice.
Many of the factors in this calculator are modifiable. Small studies suggest lifestyle programmes can shift some ageing measures, but results vary and the evidence is still developing.
No. The calculation runs in your browser and your answers are not sent to a server.
They measure different things. Blood markers reflect what is happening inside your body, including genetics and past illness, while the lifestyle mode only reflects habits.