Health & Fitness Calculators
BMI, calorie and fitness calculators to track your health.
About these calculators
Forty-four health calculators translating clinical formulas into plain answers: BMI with both WHO and Asia-Pacific cutoffs shown side by side, TDEE built from Mifflin-St Jeor or Katch-McArdle, due dates by Naegele's rule, kidney function by CKD-EPI. Each tool states which published formula it applies, because two calculators can disagree honestly simply by using different validated equations.
Nothing here diagnoses. Screening formulas flag ranges worth discussing with a doctor; they cannot see your history, medications or context. Every results panel carries that reminder, and pregnancy-related tools add cycle-length caveats since text-book averages fit fewer cycles than product pages admit.
Choosing the right calculator
Weight and body composition
BMI is the screening start; ideal-weight and healthy-weight show target ranges; body-fat (Navy method), lean-body-mass and body-type refine the picture for muscular builds where BMI misreads. Weight-loss pairs a calorie deficit with realistic timelines instead of crash-diet arithmetic.
Pregnancy
Due-date and pregnancy track gestational age from LMP; conception and ovulation estimate fertile windows; trimester marks stage transitions; pregnancy-weight-gain applies IOM ranges by starting BMI. All assume a typical 28-day cycle unless stated — irregular cycles shift every date.
Fitness and nutrition
BMR and TDEE anchor calorie targets; macro, protein and carbohydrate split those calories by diet philosophy; one-rep-max and pace serve training programming; water-intake adjusts for activity and climate. Caffeine tallies daily intake against the 400 mg adult guideline scaled by body weight.
Our health & fitnes calculator
Also available (43) — work in progress, not yet indexed
These calculators work but are still being checked for accuracy and sourcing, so they are not in search yet. They are free to use.