Home / Health Calculators

Health Calculators — Free, In Your Browser

10 free tools, no sign-up, files never uploaded.

Health and fitness calculators built on the standard published formulas: BMI, Mifflin-St Jeor BMR and calorie needs, US Navy body fat, macro splits, ideal weight ranges, hydration targets, plus pregnancy due date and ovulation estimators.

Every result is a general estimate for information, not medical advice - each page explains the method and its limits so you know how much to trust the number. Consult a healthcare professional for personal guidance.

All health calculators

  • BMI Calculator — Check your Body Mass Index with metric or imperial units, plus your healthy weight range.
  • BMR Calculator — Calories your body burns at rest, plus daily needs by activity level.
  • Body Fat Calculator — Estimate body fat percentage from tape measurements (US Navy method).
  • Ideal Weight Calculator — Ideal weight range from your height - Devine, Robinson, Miller and BMI.
  • Daily Calorie Calculator — Daily calories to maintain, lose or gain weight - from your TDEE.
  • Water Intake Calculator — A daily hydration target from your weight, exercise and climate.
  • Pregnancy Due Date Calculator — Estimated due date and how far along you are, from your last period.
  • Ovulation Calculator — Estimate your ovulation day and fertile window from your cycle.
  • Calories Burned Calculator — Calories burned by activity, weight and duration - MET-based.
  • Macro Calculator — Daily protein, carbs and fat targets for your goal and diet style.