BMI Calculator
Estimate body mass index with metric and imperial units, category interpretation and clear limitations.
Open calculatorWhat this category helps with
Health & fitness calculators help with questions where a number is useful but the assumptions matter. Start with the calculator closest to your question, then use the linked guide or formula page when units, rates, dates, local rules or source data could change the answer.
Best starting points
Calorie Calculator
Estimate daily calorie needs using researched BMR/TDEE methods and activity assumptions.
Open calculatorPregnancy Due Date Calculator
Estimate due date from last menstrual period or conception date with uncertainty clearly explained.
Open calculatorBody Fat Calculator
Estimate body fat percentage with a waist-to-height screening formula.
Open calculatorBMR Calculator
Estimate basal metabolic rate using Mifflin-St Jeor with sex coded as 1 male or 0 female.
Open calculatorMacro Calculator
Split daily calories into carbohydrate, protein and fat grams.
Open calculatorHow to choose the right calculator
- Use a broad calculator first when you need a quick estimate.
- Use a more specific calculator when rates, units, dates, eligibility or fees change the answer.
- Read assumptions before comparing results across calculators or external sources.
- For current-data topics, confirm the data source and date before relying on the result.
Calculators
BMI Calculator
Estimate body mass index with metric and imperial units, category interpretation and clear limitations.
Open calculatorCalorie Calculator
Estimate daily calorie needs using researched BMR/TDEE methods and activity assumptions.
Open calculatorPregnancy Due Date Calculator
Estimate due date from last menstrual period or conception date with uncertainty clearly explained.
Open calculatorBody Fat Calculator
Estimate body fat percentage with a waist-to-height screening formula.
Open calculatorBMR Calculator
Estimate basal metabolic rate using Mifflin-St Jeor with sex coded as 1 male or 0 female.
Open calculatorMacro Calculator
Split daily calories into carbohydrate, protein and fat grams.
Open calculatorIdeal Weight Calculator
Estimate ideal body weight using the Devine formula.
Open calculatorPregnancy Weight Gain Calculator
Compare current gain with a user-entered recommended range.
Open calculatorPregnancy Conception Calculator
Estimate conception day offset from due date day number.
Open calculatorArmy Body Fat Calculator
Estimate body-fat percentage with circumference-style inputs.
Open calculatorCarbohydrate Calculator
Calculate carbohydrate grams from calories and carbohydrate percentage.
Open calculatorLean Body Mass Calculator
Estimate lean body mass from weight and body-fat percentage.
Open calculatorHealthy Weight Calculator
Calculate the weight range for a BMI range at a given height.
Open calculatorCalories Burned Calculator
Estimate calories burned from MET, body weight and duration.
Open calculatorOne Rep Max Calculator
Estimate one-repetition maximum with the Epley formula.
Open calculatorTarget Heart Rate Calculator
Estimate target heart-rate zone from age and intensity range.
Open calculatorProtein Calculator
Calculate daily protein grams from body weight and grams per kilogram.
Open calculatorFat Intake Calculator
Calculate fat grams from calories and fat percentage.
Open calculatorTDEE Calculator
Estimate total daily energy expenditure from BMR and activity multiplier.
Open calculatorOvulation Calculator
Estimate ovulation day number from cycle length and luteal phase length.
Open calculatorConception Calculator
Estimate conception day number from last menstrual period day and ovulation offset.
Open calculatorPeriod Calculator
Estimate next period day number from last period and cycle length.
Open calculatorGFR Calculator
Estimate kidney filtration using a simplified creatinine relationship.
Open calculatorBody Type Calculator
Classify waist-to-height ratio as a simple body-shape indicator.
Open calculatorBody Surface Area Calculator
Estimate body surface area using the Mosteller formula.
Open calculatorBAC Calculator
Estimate blood alcohol concentration with a Widmark-style formula.
Open calculatorAnorexic BMI Calculator
Calculate BMI and distance below a selected BMI threshold.
Open calculatorWeight Watcher Points Calculator
Estimate generic food points from calories, fat and fiber inputs.
Open calculatorOverweight Calculator
Calculate BMI and the amount above a selected BMI threshold.
Open calculatorHeight Calculator
Convert height from centimeters to feet and inches.
Open calculatorSleep Calculator
Calculate wake time after a number of sleep cycles.
Open calculatorRace Predictor Calculator
Calculate race predictor from user-entered values with a visible formula, assumptions, limitations and source notes.
Open calculatorVO2 Max Estimate Calculator
Estimate vo2 max estimate from user-entered values with a visible formula, assumptions, limitations and source notes.
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