Start where you are

You don't need all eightto start.

The eight sort into three levels by what it costs to get the number. Level one is free and takes a day. Each level carries roughly a third of the composite (28% to 39%) — and each gives you a score of its own.

Open the calculator

Free · Nothing to install

Level 1

Free, today

Everything here is already on a phone or a wrist, or needs nothing at all. You can finish this level before lunch.

MarkerScore · Level 1

—

Computed from 4 of 8 markers

39% of composite weight

Daily Steps

47%lowerRISK OF DYING

Your phone has been counting since you bought it. Open the health app.

Grade B

Study comparison: walking 7,000 steps a day instead of 2,000 in adults (Ding 2025, 14 studies).

Free. No new hardware. Today.

Sleep Duration

32%higherRISK OF DYING

A watch, or just the time you went to bed and the time you got up.

Grade B

Study comparison: sleeping 10 hours a night instead of 7 in generally healthy populations (Yin 2017).

Free. One night to estimate, a week to be sure.

Resting Heart Rate

17%higherRISK OF DYING

Two fingers on your wrist and a clock, first thing, before you stand up.

Grade B

Study comparison: for every 10 beats a minute faster your resting pulse (Aune 2017, 48 studies). The score uses a smaller slope near 60–80 bpm.

Free. Sixty seconds.

Strength Training

17%lowerRISK OF DYING

Count the days last week you did weights, bands or push-ups on purpose.

Grade B

Study comparison: about 40 minutes a week of muscle-strengthening instead of none in adults aged 18 and up (Momma 2022, 6-study dose-response analysis).

Free. Ten seconds.

Level 2

Under $50

A cuff and three honest days of writing down what you eat. One small purchase, then they are free forever.

MarkerScore · Level 2

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Computed from 2 of 8 markers

28% of composite weight

Blood Pressure

2xhigherHEART & STROKE DEATH

An upper-arm cuff at home, or the machine in the back of most pharmacies.

Grade B

Study comparison: for every 20 points higher on your top blood pressure number, or 10 on the bottom. That heart and stroke risk keeps falling all the way down to 115/75 (Lewington 2002, ages 40 to 69).

Estimated cost: about $40 once, or free at the pharmacy.

Dietary Fiber

7%lowerRISK OF DYING

Write down everything you eat for three days and add up the fiber column.

Grade B

Study comparison: for every extra 8 grams of fiber a day in adults without chronic disease (Reynolds 2019).

Free, and the most tedious thing on this page.

Level 3

A lab

A blood draw and a treadmill — or a home kit and your watch's estimate, which are not the same thing and the calculator says so.

MarkerScore · Level 3

—

Computed from 2 of 8 markers

34% of composite weight

HbA1c

14%higherRISK OF DYING

A blood test. Ask for it by name at a physical, or use a mail-in kit.

Grade C

Study comparison: at an A1c of 6.0 to under 6.5 instead of 5.0 to under 5.5 (Schöttker 2016, 6 cohorts, 28,681 adults).

Estimated cost: often covered; $30–$60 if not.

VO₂ Max

14%lowerRISK OF DYING

A graded treadmill test with a mask. A running watch will estimate it, less well.

Grade B

Study comparison: for each 1 MET more cardio fitness — the unit a treadmill test reports — in a sample that was 81% men (Singh 2024, 42 studies).

Estimated cost: $100–$250 for the real test. Free and rough from a watch.

What a level score is not

A level's number is a weighted average over that level's markers only — the same arithmetic as the full composite, run on fewer inputs. It is not a third of your MarkerScore, and two level scores do not add up to anything. Finishing Level 1 means you have a ranking built on 39% of the weight, not 39% of an answer.

Ready when you are

Start with level one.

Four numbers you already have, or can get before lunch. The calculator fills in the rest with estimates and tells you which ones they are.

Open the calculator

Free · Nothing to install