Health & Fitness
BMI, BMR, calories burned, ideal weight, macros, body fat, and 20+ health tools.
Calculators
A1C Calculator — Estimated Average Glucose
Convert HbA1c percentage to estimated average blood glucose (eAG) in mg/dL or mmol/L. Essential for diabetes management. Free A1C calculator.
Open calculatorAlcohol Units Calculator
Calculate alcohol units in any drink by volume and ABV. Track your weekly alcohol intake against health guidelines. Free alcohol units calculator.
Open calculatorBlood Alcohol Content (BAC) Calculator
Estimate your Blood Alcohol Content (BAC) based on drinks consumed, body weight, sex, and time. For educational purposes only. Never drink and drive.
Open calculatorBMI Prime Calculator
Calculate your BMI Prime — ratio of your BMI to the healthy limit of 25. Check if you are in the optimal weight range. Free BMI Prime calculator.
Open calculatorBMI Calculator — Free & Instant
Calculate your Body Mass Index instantly. Enter your weight and height to find out if you are underweight, normal, overweight, or obese. Free BMI calculator.
Open calculatorBMR Calculator — Basal Metabolic Rate
Calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation. Find out how many calories your body burns at rest per day.
Open calculatorBody Fat Percentage Calculator — Free & Instant
Estimate your body fat percentage using the US Navy method. Enter neck, waist, and hip measurements for an instant, accurate body fat estimate.
Open calculatorBody Surface Area Calculator
Calculate your Body Surface Area (BSA) using the Mosteller formula. Used in medicine for drug dosing and clinical calculations. Free BSA calculator.
Open calculatorCaffeine Half-Life Calculator
Calculate how much caffeine remains in your system after any number of hours. Find the best time to stop drinking coffee for good sleep. Free calculator.
Open calculatorCalorie & TDEE Calculator — Free Daily Calorie Needs
Calculate your Total Daily Energy Expenditure (TDEE) and daily calorie needs for weight loss, maintenance, or muscle gain. Free, instant, science-based.
Open calculatorCalories Burned Calculator
Calculate calories burned during exercise. Enter your weight, activity, and duration to find out how many calories you burned. Free and instant.
Open calculatorCalories to Lose Weight Calculator
Calculate how many calories you should eat daily to reach your weight loss goal. Based on TDEE and calorie deficit science. Free weight loss calorie calculator.
Open calculatorCat Age Calculator — Cat Years to Human Years
Convert your cat's age to human years. Based on feline developmental stages. Find out how old your cat is in human equivalent years. Free cat age calculator.
Open calculatorHeart Rate Zone Calculator
Calculate your maximum heart rate and target heart rate training zones based on your age. Free heart rate zone calculator.
Open calculatorIdeal Weight Calculator
Calculate your ideal body weight based on your height and sex using the Devine formula. Free and instant ideal weight calculator.
Open calculatorLean Body Mass Calculator
Calculate your Lean Body Mass (LBM) — the weight of everything in your body except fat. Free lean body mass calculator using the Boer formula.
Open calculatorMacro Calculator — Daily Macronutrients
Calculate your daily macronutrient targets (protein, carbs, fat) based on your calorie goal and diet type. Free macro calculator.
Open calculatorMaximum Heart Rate Calculator
Calculate your maximum heart rate by age. Find your target heart rate zones for fat burning, aerobic fitness, and peak performance. Free MHR calculator.
Open calculatorOvulation Calculator — Find Your Fertile Window
Calculate your ovulation day and fertile window based on your last period and cycle length. Free ovulation calculator.
Open calculatorPace Calculator — Running & Walking Pace
Calculate your running or walking pace. Find pace from time and distance, or estimate finish time from pace. Free pace calculator for runners.
Open calculatorPeriod Calculator — Next Period Date
Calculate how many days until your next period based on your last period date and cycle length. Free menstrual cycle calculator.
Open calculatorPregnancy Due Date Calculator — Free EDD Estimator
Calculate your pregnancy due date from your last period or conception date. Find your due date and current week of pregnancy. Free due date calculator.
Open calculatorPregnancy Weight Gain Calculator
Calculate recommended total pregnancy weight gain based on your pre-pregnancy BMI. Based on IOM guidelines. Free pregnancy weight gain calculator.
Open calculatorProtein Calculator — Daily Protein Intake
Calculate your daily protein requirement based on your weight, activity level, and goal. Free protein intake calculator.
Open calculatorSleep Calculator — How Much Sleep Do You Need?
Calculate how much sleep you need based on your age. Free sleep duration calculator backed by sleep science recommendations.
Open calculatorSteps to Calories Calculator
Convert your daily step count to calories burned. Free steps to calories calculator based on your weight and stride.
Open calculatorVO2 Max Calculator — Cardiorespiratory Fitness
Estimate your VO2 max (maximum oxygen uptake) using your resting and maximum heart rates. Find your cardiorespiratory fitness level. Free VO2 max calculator.
Open calculatorWaist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio (WHR) to assess your health risk. A WHR above 0.90 (men) or 0.85 (women) indicates higher risk. Free calculator.
Open calculatorWater Intake Calculator — Daily Hydration Needs
Calculate your recommended daily water intake based on your weight and activity level. Free hydration calculator for adults.
Open calculatorWeight Loss Time Calculator
Calculate how long it will take to reach your goal weight based on your daily calorie deficit. Plan your weight loss timeline. Free calculator.
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