Health Calculators
Free online health and fitness calculators. All results are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before making decisions about your health.
Body & Weight
- BMI Calculator — Body Mass Index using WHO categories, metric and imperial units
- Calorie Calculator — Daily calorie needs using Mifflin-St Jeor with activity level multiplier
- BMR Calculator — Basal Metabolic Rate: calories burned at complete rest
- TDEE Calculator — Total Daily Energy Expenditure: BMR × activity factor
- Body Fat Calculator — Body fat percentage using the US Navy circumference method
- Ideal Weight Calculator — Devine, Robinson, Miller, and Hamwi formula comparison
Nutrition & Goals
- Macro Calculator — Protein, carbs, and fat targets based on TDEE and fitness goal
- Water Intake Calculator — Daily water needs based on weight and activity level
- Sleep Calculator — Optimal bedtime based on 90-minute sleep cycles
- Heart Rate Zone Calculator — Karvonen formula with 5 training zones
- BAC Calculator — Blood alcohol content estimate using Widmark formula. For informational purposes only — never drink and drive.
Women's Health & Fertility
- Pregnancy Calculator — Due date, trimester timeline, and key milestone dates from LMP
- Ovulation Calculator — Fertile window from LMP and cycle length
- Pace Calculator — Running pace from distance and time, with splits table for common race distances