Health API — BMI, BMR, TDEE, and 4-formula ideal weight calculator
The /health namespace covers the standard evidence-based health calculators — BMI, BMR, TDEE, calorie deficit, sleep needs, VO2max — with ideal weight averaging four named formulas instead of one.
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What's included in /health
Ideal weight, 4 formulas
Devine, Robinson, Miller, and Hamwi formulas computed separately and presented together, not collapsed into one number.
BMR and TDEE
Basal metabolic rate and total daily energy expenditure using standard, named formulas.
Calorie deficit planning
Computes the deficit needed for a target weight-loss rate using the standard energy-balance model.
VO2max estimation
Cardiovascular fitness estimate from caller-supplied inputs, no wearable required.
Sleep needs by age
Age-appropriate sleep duration recommendations based on NSF/AAP guidelines.
Start using the BMI calculator API today
Free tier — 500 calls/month, no credit card. Upgrade when you need more.
Frequently asked questions
Why four ideal-weight formulas instead of one?
Each formula was developed independently and produces slightly different results — showing all four is more honest than picking one and presenting it as definitive.
Is this a substitute for medical advice?
No — these are standard population-level formulas for general estimation, not personalized medical guidance.
Is there a free tier?
Yes — 500 calls/month forever, no credit card.
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