CALCULATOR CATEGORY
Health & Wellness Calculators
Free health and wellness calculators for BMI, calories, BMR, TDEE, body composition, hydration and reproductive planning.
16 calculators in this category. Choose a tool below.
Know the difference between a screening estimate and a diagnosis
Health calculators can help explain common measurements such as BMI, BMR, TDEE, calorie estimates and ranges. These numbers are useful for education and planning, but they simplify real bodies into mathematical relationships. Read the limitations on the calculator page and avoid treating a screening estimate as a diagnosis or a personalized treatment recommendation.
- Use current measurements and the unit system shown by the calculator.
- Understand what the formula measures and what it does not measure.
- Use an appropriate healthcare professional for symptoms, diagnosis, treatment or individualized medical decisions.
Read more: practical calculator guide
BMI
Calculate adult body mass index, weight category and a BMI based healthy weight range with US or metric inputs.
Calorie
Estimate resting energy needs, maintenance calories and goal calorie ranges using established adult energy equations and activity levels.
BMR
Estimate basal metabolic rate using the Mifflin St Jeor equation and compare it with a second reference formula.
TDEE
Estimate total daily energy expenditure across multiple activity levels and compare maintenance calorie scenarios.
Body Fat
Estimate adult body fat percentage using the US Navy circumference method with body composition category context.
Ideal Weight
Compare four widely used adult ideal body weight formulas and see their average reference estimate.
Healthy Weight Range
Estimate the adult weight range associated with BMI 18.5 to 24.9 for a given height in US or metric units.
Macro
Build daily protein, carbohydrate and fat targets from a calorie target using flexible macro percentages.
Protein Intake
Estimate an adult daily protein range based on body weight, activity level and training goal.
Water Intake
Estimate a practical daily fluid planning target from body weight, activity, climate and pregnancy or breastfeeding status.
Pregnancy Due Date
Estimate due date, gestational age and trimester milestone dates from the first day of the last menstrual period and cycle length.
Pregnancy Weight Gain
Compare pregnancy weight gain with Institute of Medicine reference ranges based on prepregnancy BMI and singleton or twin pregnancy.
Ovulation
Estimate ovulation date and fertile window from the first day of the last period and typical cycle length.
Menstrual Cycle
Project upcoming period dates, cycle phases and estimated fertile windows from your typical cycle pattern.
Heart Rate Zone
Calculate training heart rate zones using age predicted maximum heart rate and the Karvonen heart rate reserve method.
Blood Pressure Range
Classify an adult blood pressure reading using current common category thresholds and calculate pulse pressure and mean arterial pressure.