BMI, body fat, calories, macros, pregnancy, heart rate, and 50+ more health tools.
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BMI, body composition, calorie tracking, heart rate training zones, medication dosing — this section covers the health math that most people either guess at or pay someone else to figure out. Every tool here is grounded in clinical formulas and exercise science, not bro-science or guesswork.
I source every formula from peer-reviewed research and clinical guidelines (Mifflin-St Jeor for BMR, Katch-McArdle for body composition, WHO standards for BMI). These calculators are for informational purposes and should complement — not replace — actual medical advice. Walking into a doctor's appointment with your own numbers makes for a better conversation.
BMI, body fat percentage, lean mass, ideal weight — the numbers that actually tell you where you stand. Each tool uses multiple validated formulas so you're not relying on just one equation.
Calculate your daily calorie needs, set macro targets, and plan your nutrition. Start with TDEE to find your maintenance calories, then use Macros to dial in protein, carbs, and fat.
Pace calculators, heart rate training zones, VO2max estimates, and calorie burn tracking. Whether you're training for a 5K or just trying to figure out what zone 2 actually means.
Due date estimation, ovulation tracking, pregnancy weight gain, and week-by-week milestones. All based on standard clinical guidelines (Naegele's rule, IOM recommendations).
A1C conversion, kidney function (GFR), blood pressure interpretation, sleep cycle planning. These are clinical-grade tools — still worth discussing results with your doctor, but great for going in prepared.