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Health & longevity calculators
A small set of evidence-based tools that turn the research into a single number you can act on — how much protein to eat, how fit your heart really is, and where your waistline puts your risk. Each one shows its formula and cites its sources.
VO₂ Max & Fitness Age
→Turn your resting heart rate into a cardio-fitness score — and a fitness age.
Daily Protein Target
→How much protein to hold onto muscle as you age, split per meal.
Waist-to-Height Ratio
→A 10-second tape-measure check that out-predicts BMI.
Supplement Finder
→Match supplements to your goal by the strength of the evidence.
These tools are for general education, not medical advice. If you have a health condition or take medication, check with a clinician before acting on any result.