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Blood Age Calculator

How old does your blood say you are? Type in nine results from a routine blood test and get your blood age from a published formula. Free, and nothing you type leaves your browser.

Enter your numbers

All nine from the same test, taken fasting and when you were well. The unit is printed next to each result on your report.

In whole years, 20 to 84.

Liver panel

Kidney panel

Fasting sample only

Inflammation

Full blood count

fL

Full blood count

%

Full blood count

U/L

Liver panel

×10⁹/L

Full blood count

See what moves it, then work on it

His Form OS reads your whole report, shows which results are pushing your blood age up, and builds a 12-week training, food and sleep plan around them. It runs in your own Claude account.

See His Form OS →

Don't know your numbers?

In Bali or Jakarta, a nurse comes to you. FORM's blood tests include the nine results this calculator needs, with a report that puts every result against a tighter range than the lab's.

See the blood tests →

How the blood age is worked out

In 2018 a research group led by Morgan Levine looked at 42 routine blood measures in 9,926 US adults who had been followed for 23 years. Nine of those measures, together with age, said the most about how long people went on to live. The researchers turned that into a single figure in years, which they called Phenotypic Age, and then checked it on a further 6,209 adults.

This calculator runs that formula on your numbers. If your nine results look like those of a typical 35-year-old in the study, your blood age is 35, whatever your birthday says.

It is a statement about groups of people, not a prediction about you. A single test is a snapshot. The useful part is the direction it moves when you test again.

The nine results, and where to find them

ResultOn your report underUnits
AlbuminLiver panelg/L or g/dL
CreatinineKidney panelµmol/L or mg/dL
Fasting glucoseFasting sample onlymmol/L or mg/dL
hs-CRPInflammationmg/L or mg/dL
LymphocytesFull blood count% or ×10⁹/L
MCV (red cell size)Full blood countfL
RDW (red cell size spread)Full blood count%
ALP (alkaline phosphatase)Liver panelU/L
White blood cellsFull blood count×10⁹/L

White blood cells in ×10⁹/L is the same number as ×10³/µL. If your report gives lymphocytes as a count rather than a percentage, choose ×10⁹/L and the calculator works out the share.

Questions

What is blood age?

Blood age is an estimate of how old your body looks from a routine blood test, compared with your actual age. This calculator uses a published formula, often called Phenotypic Age, that combines nine common blood results with your age. It is an estimate, not a diagnosis, and it says nothing about any one disease.

Which formula does this calculator use?

The Phenotypic Age formula from Levine and colleagues, published in the journal Aging in 2018. It was built from 9,926 US adults followed for 23 years and then checked on a further 6,209 adults. We use the weights from the paper as its authors published them in their own reference code.

Which blood results do I need?

Nine, all from the same test: albumin, creatinine, fasting glucose, hs-CRP, lymphocytes, MCV, RDW, ALP and white blood cells. Most come with a full blood count plus a liver and kidney panel. Fasting glucose and hs-CRP are sometimes ordered separately.

Is anything I type sent or stored?

No. The sum is done in your browser. The numbers you type are not sent to FORM or anyone else, and they are gone when you close the page.

My blood age is older than my actual age. What now?

Treat it as a starting point. One test is a snapshot, and results move with sleep, training, illness and what you ate. If any single result is outside your lab's range, that is a question for your doctor. The estimate itself is not a diagnosis.

Why won't it give a blood age when hs-CRP is above 10 mg/L?

An hs-CRP that high usually means an infection or a very hard training session in the days before the test. A blood age worked out from that sample would mislead you. Use a test taken when you were well and rested.

Can I use a glucose result that wasn't fasting?

No. The formula expects a fasting sample. A glucose taken after food reads higher and would make your blood age look older than it is.

Source: Levine ME and colleagues. An epigenetic biomarker of aging for lifespan and healthspan. Aging (Albany NY). 2018;10(4):573-591. Read the paper. This page is general information, not medical advice. If a result worries you, talk to a doctor.