Health Calculators
46 free calculatorsHealth metrics are only useful when you understand what they measure and what they don't. These calculators use clinically validated formulas and explain the assumptions behind each one — including their limitations.
Use them as a starting point for conversations with healthcare providers, not as a replacement for professional advice.
Adderall Dosage Calculator
Calculate safe Adderall dosage recommendations based on age, weight, and condition severity. Get personalized dosing guidance for ADHD treatment.
Adjusted Age Calculator
Calculate adjusted age for premature babies. Determines corrected age based on gestational age at birth and current chronological age for development tracking.
Adjusted Weight Calculator
Calculate adjusted body weight for medical dosing and clinical use. Essential for healthcare professionals determining medication dosages based on ideal vs a...
Aleve Dosage Calculator
Calculate safe Aleve (naproxen sodium) dosage based on your weight and pain level. Get recommended doses for adults and children with safety guidelines.
Arterial Age Calculator
Calculate your arterial age based on cardiovascular risk factors. Compare your biological vascular age to chronological age instantly.
Basal Metabolic Rate Calculator
Calculate your basal metabolic rate (BMR) using the Mifflin-St Jeor equation. Enter age, weight, height, and sex to see daily calories burned at rest.
Biological Age Estimator
Calculate your biological age based on health markers and lifestyle factors. Compare your body's true age to chronological age with this estimator.
Birthweight Percentile Calculator
Calculate your baby's birthweight percentile compared to standard growth charts. Enter weight, gestational age, and sex to see if birthweight is typical.
Blood Pressure Calculator
Calculate your blood pressure category and health risk. Free tool determines if readings are normal, elevated, or high blood pressure stage 1 or 2.
Blood Pressure Category Explainer
Check your blood pressure category with our calculator. Enter systolic and diastolic readings to see if your BP is normal, elevated, or high blood pressure.
BMI Calculator
Calculate your Body Mass Index (BMI) instantly. Enter height and weight to determine if you're underweight, normal, overweight, or obese.
BMI Calculator
Calculate your Body Mass Index (BMI) instantly. Enter height and weight to see your BMI category and health range in metric or imperial units.
BMI Kids Calculator
Calculate BMI percentile for children aged 2-20 years. Get accurate body mass index assessment with age and gender-specific growth charts for kids.
Body Fat Calculator
Calculate your body fat percentage using Navy Method measurements. Get accurate results with waist, neck, and hip measurements for fitness tracking.
Body Fat Percentage Calculator
Calculate your body fat percentage using Navy method measurements. Find out if your body composition is healthy for your age and fitness goals.
Body Water Calculator
Calculate your total body water percentage and volume using Watson formula. Enter age, weight, height, and gender for accurate hydration assessment.
Caffeine Half-Life Calculator
Calculate how long caffeine stays in your system. Enter caffeine amount and consumption time to see remaining caffeine levels and when it clears your body.
Calorie Calculator
Calculate daily calories needed to maintain, lose, or gain weight. Enter age, height, weight, and activity level to get your personalized calorie target.
Calorie Deficit Calculator
Calculate your daily calorie deficit to reach your weight loss goals. Enter current weight, target weight, and timeline to find exactly how many calories to ...
Calories Burned Calculator
Calculate calories burned during exercise based on activity type, duration, and body weight. Get accurate estimates for walking, running, cycling, and 50+ ac...
Creatinine Clearance Calculator
Calculate kidney function with creatinine clearance using the Cockcroft-Gault formula. Enter age, weight, gender, and serum creatinine for instant results.
Due Date Calculator
Calculate your pregnancy due date from last menstrual period or conception date. Free due date calculator with accurate 40-week gestation timeline.
Health Calculator
Calculate your BMI, daily calorie needs, and ideal weight range. Enter height, weight, age, and activity level for personalized health metrics.
Heart Rate Calculator
Calculate your maximum heart rate and target heart rate zones for optimal exercise intensity. Free heart rate calculator with age-based formulas.
Heart Rate Zone Calculator
Calculate your target heart rate zones for optimal training. Enter your age and resting heart rate to find fat burn, cardio, and peak zones instantly.
Hydration Calculator
Calculate your daily water intake needs based on weight, activity level, and climate. Get personalized hydration recommendations in liters or gallons.
Ideal Weight Calculator
Calculate your ideal weight range using BMI-based formulas. Enter height, age, and gender to find healthy weight targets for optimal wellness and fitness goals.
Intermittent Fasting Calculator
Calculate your intermittent fasting schedule with eating and fasting windows. Enter your preferred fasting method and start time to see your daily eating per...
Macro Calculator for Weight Loss
Calculate daily protein, carbs, and fat intake for weight loss based on your goals. Enter stats, activity level, and target deficit for personalized macros.
Macronutrient Calculator
Calculate your daily macronutrient needs (protein, carbs, fats) based on weight, activity level, and fitness goals. Free macro calculator.
Metabolic Rate Calculator
Calculate your basal metabolic rate (BMR) and daily calorie needs using the Mifflin-St Jeor equation. Free metabolic rate calculator with activity levels.
Ovulation Calculator
Calculate your ovulation date and fertile window based on cycle length and last period. Find your best days to conceive or track your cycle.
Pregnancy Calculator
Calculate your due date, current pregnancy week, and key milestones. Enter your last menstrual period or conception date to track your pregnancy timeline.
Pregnancy Weight Gain Calculator
Calculate healthy pregnancy weight gain based on your pre-pregnancy BMI and current week. Get personalized recommendations following medical guidelines.
Protein Intake Calculator
Calculate your daily protein needs based on weight, activity level, and goals. Get personalized protein intake recommendations for muscle building.
Running Pace Calculator
Calculate your running pace, race time, or distance. Enter any two values to find the third. Perfect for training plans and race goals.
Sleep Calculator
Calculate optimal bedtime and wake-up time based on sleep cycles. Find out when to sleep and wake up to feel refreshed and avoid grogginess.
Sleep Cycle Calculator
Calculate optimal bedtime or wake-up time based on 90-minute sleep cycles. Enter your preferred sleep or wake time to find the best schedule for feeling refr...
Sleep Debt Calculator
Calculate your sleep debt by comparing actual sleep hours to recommended sleep needs. Track sleep deficit and recovery time for better health.
Supplement Evidence Grader
Grade supplement evidence strength using systematic criteria. Assess study quality, consistency, and clinical relevance for informed health decisions.
TDEE Calculator
Calculate your Total Daily Energy Expenditure (TDEE) to determine exactly how many calories you burn each day based on your body size, age, and activity level.
VO2 Max Calculator
Calculate your VO2 max to measure cardiovascular fitness and aerobic capacity. Find your fitness level compared to age and gender standards.
VO2 Max Estimator
Calculate your VO2 max using simple fitness tests. Find your cardiovascular fitness level and track aerobic capacity improvements over time.
Waist to Hip Ratio Calculator
Calculate your waist to hip ratio (WHR) to assess body fat distribution and health risks. Enter waist and hip measurements to get your ratio instantly.
Water Intake Calculator
Calculate your daily water intake needs based on weight, activity level, and climate. Get personalized hydration recommendations for optimal health.
Zone 2 Training Calculator
Calculate your Zone 2 training heart rate range for optimal aerobic base building and fat burning. Enter age and resting heart rate for personalized training...