Free Online Health & Fitness Calculators

BMI & Body Composition Calculators measure body size and composition beyond a single BMI number. Calculate BMI (body mass index) for adults, kids, teens, men, or women, or use the BMI prime calculator and BMI weight loss calculator to interpret and act on your result. Body composition tools like the Navy body fat calculator, Army body fat calculator, and skinfold body fat calculator estimate fat percentage, while lean body mass and FFMI (fat-free mass index) calculators focus on muscle mass.

This section also includes newer body shape metrics — ABSI (a body shape index), BAI (body adiposity index), BRI (body roundness index), and RFM (relative fat mass) — plus body frame size, body type (ectomorph/mesomorph/endomorph), and ponderal index calculators for a fuller picture of body composition.

Blood & Substance Calculators cover blood alcohol, screening questionnaires, and related lab values. Calculate blood alcohol content (BAC) with the BAC calculator, or screen for risky drinking with the AUDIT score, AUDIT-C, and CAGE questionnaire calculators. The alcohol unit calculator and alcohol dilution calculator handle everyday drink math, while the nicotine clearance calculator and cigarette cost calculator track smoking-related habits.

This section also includes a blood donation eligibility calculator, blood type compatibility calculator, serum osmolality calculator, and caffeine calculator for other blood- and substance-related questions.

Body Measurements Calculators cover the everyday and clinical measurements taken of the human body. Calculate BSA (body surface area) or waist to height ratio and waist to hip ratio, or predict adult height with the height calculator (adult height predictor). Parents can track child height percentile, child weight percentile, and baby growth percentile, while the wrist size calculator, bra size calculator, and draw length calculator cover sizing for specific needs.

This section also includes a desk height calculator, height converter, IQ percentile calculator, and weight loss percentage calculator for tracking other personal metrics.

Calories & Energy Calculators estimate how many calories your body needs each day. Calculate BMR (basal metabolic rate) or TDEE (total daily energy expenditure) using the Harris-Benedict or Katch-McArdle formulas, or use the EER calculator (estimated energy requirement) for a government-standard estimate. The calorie deficit calculator and maintenance calorie calculator help set intake targets for weight loss or weight maintenance, while RMR (resting metabolic rate) and BEE (basal energy expenditure) calculators offer alternative baseline estimates.

This section also includes a calorie calculator, calorie intake calculator, simple calorie intake calculator, and meal calorie calculator for everyday calorie tracking.

Calories Burned Calculators estimate energy expenditure for nearly any activity. Calculate calories burned running, walking, swimming, or cycling, or use the calories burned by heart rate calculator for a more personalized estimate. Strength and HIIT-style activities are covered by burpee, push-ups, jump rope, and weight lifting calorie calculators, while the elliptical calorie calculator and rowing calories burned calculator cover cardio machines.

This section also includes calorie calculators for yoga, Pilates, dancing, stairs, standing, housework, snow shoveling, sauna, and skating, plus a steps to calories calculator for converting daily step counts into an energy estimate.

Cardiovascular Clinical Calculators cover the risk scores and diagnostic tools used in cardiology and emergency medicine. Calculate stroke and clotting risk with the CHA2DS2-VASc score, CHADS2 score, and HAS-BLED score, or assess chest pain with the HEART score, TIMI score, and Wells score (PE). The GRACE calculator and Duke treadmill score estimate cardiac risk after a cardiac event or during stress testing, while cardiac index, cardiac output, and PVR calculators measure heart function directly.

This section also includes general severity scoring tools like APACHE II, SOFA score, and Modified Early Warning Score (MEWS), plus specialized calculators for QTc (corrected QT interval), ABI (ankle-brachial index), aortic and mitral valve area, arterial age, ICH volume, the NIH Stroke Scale (NIHSS), and the 6 minute walk test for a wide range of cardiovascular and neurological assessments.

Cholesterol & Metabolic Calculators assess cardiovascular and metabolic risk from lab values. Calculate LDL and VLDL cholesterol, or find your overall cholesterol ratio, and convert between cholesterol units used in different countries. The ASCVD risk calculator, Framingham risk score, and 10-year CVD risk calculator estimate long-term cardiovascular disease risk, while the metabolic syndrome calculator and gout diagnosis calculator flag other metabolic conditions.

Cycling Calculators cover performance metrics, gearing, and equipment sizing for road, gravel, and indoor cycling. Calculate FTP (functional threshold power) and cycling power zones to structure training, or use the cycling TSS calculator (training stress score) to measure workout load. Bike fit and gearing tools include the bike size calculator, bike gear calculator, chain length calculator, and spoke length calculator, while cycling speed vs grade and hill climbing power calculators model performance on different terrain.

This section also includes Zwift-specific tools like the Zwift route time calculator, Zwift segment time calculator, and cycling category calculator (Zwift), plus watts per kg, cycling drag coefficient, e-bike range, tire pressure (cycling), and a cycling to running converter for cross-training athletes.

Diabetes & Blood Sugar Calculators help track and interpret blood glucose data. Calculate A1c (hemoglobin A1c) and estimated average glucose, or convert blood sugar readings between mg/dL and mmol/L with the blood sugar converter. The HOMA-IR calculator and QUICKI calculator estimate insulin resistance from fasting glucose and insulin values, while the diabetic ketoacidosis calculator flags a serious diabetes complication.

This section also includes a diabetes risk calculator, carb counting calculator, insulin dosage calculator, and Warsaw method calculator for insulin-to-carb ratio calculations.

Heart Rate & Cardiovascular Calculators help you train and monitor your heart rate effectively. Calculate max heart rate and target heart rate, or use the Karvonen formula calculator and heart rate zone calculator to set training zones based on resting heart rate. Endurance athletes can use the anaerobic threshold calculator, VO2 max calculator, and zone 2 heart rate calculator, while sport-specific versions cover cycling and triathlon heart rate zones.

This section also includes blood pressure, MAP (mean arterial pressure), pulse pressure, and rate pressure product calculators for cardiovascular health metrics, plus cardiac output, stroke volume, resting heart rate, and heart rate recovery calculators.

Hormones & Endocrine Calculators estimate hormone levels relevant to metabolism and reproductive health. Calculate free testosterone from total testosterone and binding proteins, or check cortisol level and DHEA level against reference ranges. The thyroid function calculator interprets thyroid hormone results for a general picture of endocrine health.

Hydration Calculators help you replace fluids and electrolytes lost through sweat and daily activity. Calculate daily water intake with the water intake calculator, or estimate sweat rate during exercise to fine-tune fluid replacement. The electrolyte calculator and DIY sports drink calculator help you mix a homemade rehydration drink with the right balance of sodium, potassium, and carbohydrates.

Ideal Weight Calculators estimate a healthy target weight using several established formulas. Use the ideal body weight calculator (Devine formula) or ideal weight calculator for a quick reference range, or check healthy weight for height with the healthy weight for height calculator. The ideal weight by body frame calculator adjusts targets for frame size, while the target weight calculator and healthy weight calculator help set a realistic goal.

Kidney & Renal Calculators interpret lab values used to assess kidney function. Calculate GFR (glomerular filtration rate) or creatinine clearance using the Cockcroft-Gault formula, or check the BUN to creatinine ratio for kidney health screening. The anion gap calculator and osmolality calculator support broader metabolic assessment, while the fractional excretion of sodium (FENa) calculator and sodium correction calculator address more specific kidney and electrolyte questions.

Liver & GI Calculators cover the scoring systems used to assess liver and gastrointestinal disease severity. Calculate the MELD score or Child-Pugh score to estimate liver disease severity, or use Ranson's criteria and the Glasgow-Blatchford score for pancreatitis and GI bleeding risk. The SAAG calculator helps classify the cause of ascites, while the fiber intake calculator and gut microbiome score calculator take a more everyday approach to digestive health.

Macronutrients & Diet Calculators break your food intake down into protein, carbs, fat, and micronutrients. Calculate protein, carb, and fat intake targets with the protein calculator, carb calculator, and fat intake calculator, or use the macro calculator and IIFYM calculator (if it fits your macros) for a full macro breakdown. The keto calculator and net carbs calculator support low-carb eating, while glycemic index and glycemic load calculators assess how foods affect blood sugar.

This section also includes vitamin A, vitamin D, and general vitamin and micronutrient calculators, plus a DRI calculator (dietary reference intake), fiber calculator, added sugar intake calculator, sodium in salt calculator, calorie density calculator, diet risk score calculator, and a breastfeeding calorie calculator for nutrition needs during lactation.

Mental Health & Wellness Calculators use validated screening tools to check in on common wellbeing concerns. Screen for anxiety with the GAD-7 anxiety calculator or depression with the PHQ-9 depression calculator, or check daytime sleepiness with the Epworth sleepiness scale. The fatigue severity scale calculator and stress level calculator track other common wellbeing markers, while the screen time calculator and dog walking health benefits calculator look at everyday habits that affect mental health.

Military Fitness Calculators score physical fitness tests used by different branches of the armed forces. Calculate your APFT score (Army Physical Fitness Test) or Air Force PT test score, or use the Navy PRT calculator and IPPT calculator for Navy and international physical readiness tests. Each calculator applies the official scoring standards for that test's push-up, sit-up, and run components.

Miscellaneous Health Calculators cover health topics that don't fit neatly into a single category. Estimate biological age or health age with the biological age calculator and health age questionnaire calculator, or calculate body water and blood volume for a fuller physiological picture. The DASI calculator (Duke Activity Status Index) and sitting time risk calculator assess functional capacity and sedentary risk, while the caloric needs during illness calculator adjusts intake for recovery.

This section also includes a posture score calculator, noise pollution calculator, protein needs for seniors calculator, life insurance needs calculator, time of death calculator, bedridden patient height calculator, and a dog age calculator for pet owners.

Pediatric Health Calculators track growth, dosing, and newborn assessment for infants and children. Calculate an APGAR score or Ballard score for newborn assessment, or track child growth chart and child BMI percentiles over time. The pediatric dosage calculator and pediatric fluid calculator adjust medication and fluid amounts for a child's weight, while the pediatric GCS (Glasgow Coma Scale) calculator assesses consciousness level in children.

This section also includes a baby due date calculator, infant feeding calculator, and neonatal weight conversion calculator for newborn care.

Pharmacology & Dosing Calculators support medication dosing and drug-related lab calculations. Calculate a drug dosage or IV drip rate, or use the ideal body weight for dosing calculator to base medication amounts on the right weight metric. The Parkland formula calculator estimates fluid resuscitation needs for burn patients, while the sodium bicarbonate deficit calculator and corrected calcium calculator adjust for lab abnormalities.

This section also includes an APACHE II calculator, absolute neutrophil count calculator, creatinine clearance (Cockcroft-Gault) calculator, and NNT calculator (number needed to treat) for evaluating treatment effectiveness.

Pregnancy & Fertility Calculators cover the full timeline from trying to conceive through delivery. Calculate ovulation and fertile window with the ovulation calculator and BBT calculator (basal body temperature), or estimate due date with the due date calculator, EDD calculator, and pregnancy calculator. Fertility treatment tools include the Clomid ovulation calculator, IVF due date calculator, and egg freezing calculator, while conception, implantation, and luteal phase calculators track early pregnancy signs.

This section also includes ultrasound-based tools like crown-rump length, gestational age, mean sac diameter, and nuchal translucency calculators, plus a Bishop score calculator, fundal height calculator, pregnancy weight gain calculator, hCG levels calculator, sperm analysis calculator, and breast cancer risk calculator (Gail model) for broader reproductive health assessment.

Respiratory Calculators assess lung function and respiratory illness risk. Calculate peak flow or oxygen saturation to check breathing function, or use the A-a gradient calculator and Winter's formula calculator for acid-base and gas exchange analysis. The CURB-65 score assesses pneumonia severity, the Centor score screens for strep throat, and the lung cancer risk calculator estimates risk based on smoking history and other factors.

Running & Jogging Calculators cover pace, training, and race prediction for runners of every level. Calculate your 5K pace, 10K pace, half marathon pace, or marathon pace, or use the race predictor calculator and race time improvement calculator to project future performances. The training pace calculator and age grade running calculator help structure workouts and compare times across age groups, while the Cooper test calculator (12-minute run) estimates VO2 max from a timed run.

This section also includes stride length, running split, and running calorie calculators, plus steps to miles, steps to kilometers, and miles to steps converters for tracking distance from a step count.

Skin & Dermatology Calculators assess skin conditions and sun exposure risk. Calculate burn surface area using the rule of nines, or score psoriasis severity with the PASI score calculator and eczema severity with the EASI score calculator. The UV index calculator and sunscreen calculator help plan safe sun exposure and reapplication timing.

Sleep Calculators help you understand and improve your sleep quality. Calculate sleep cycles with the sleep calculator and sleep cycle calculator to time bedtime around 90-minute cycles, or track sleep debt and sleep efficiency over time. The circadian rhythm calculator estimates your natural sleep-wake timing, while the AHI calculator (apnea-hypopnea index) and STOP-BANG calculator screen for sleep apnea risk.

This section also includes a REM sleep calculator and pediatric Epworth sleepiness scale for assessing sleep patterns in children.

Sports Statistics Calculators compute the performance metrics used across major sports. Calculate batting average and ERA (earned run average) for baseball, or on-base percentage, slugging percentage, and WAR (wins above replacement) for a fuller offensive picture. Basketball stats are covered by true shooting percentage, eFG (effective field goal percentage), and game score calculators, while passer rating covers NFL quarterback performance.

This section also includes cricket-specific tools like batting strike rate, bowling average, net run rate, and the Duckworth Lewis calculator, plus an Elo rating calculator, goalie save percentage, fielding percentage, GAA (goals against average), heptathlon score, and accumulator bet calculators for other sports and betting scenarios.

Sports-Specific Calculators cover niche equipment and performance questions for individual sports. Calculate ski size or DIN setting (ski bindings) for skiing, or use the hull speed calculator and windsurfing calculator for water sports. Archers can use the arrow FOC calculator, while anglers have the fish weight calculator and fishing reel line capacity calculator.

This section also includes an American football position calculator, golf altitude adjustment calculator, kiteboarding calculator, scuba weight calculator, tennis ball usage calculator, and pool table room size calculator for other sport-specific planning needs.

Strength Training Calculators help you plan and track lifting progress. Calculate your one rep max (1RM) or use the 5/3/1 calculator (Wendler) to structure a strength program around percentages of your max. The bench press calculator, squat max calculator, and deadlift max calculator estimate max lifts for the big three, while the Wilks calculator and strength standards calculator compare your lifts against other lifters by bodyweight.

This section also includes an RPE calculator (rate of perceived exertion), volume load calculator, workload adjustment calculator, barbell racking calculator, and Russian squat program calculator for programming and tracking training load.

Swimming Calculators cover pace, training load, and performance metrics in the pool and open water. Calculate swim pace and swim split times, or use the CSS calculator (critical swim speed) and SWOLF score calculator to measure swimming efficiency. The swimming TSS calculator (training stress score) tracks training load, while the pool length converter (yards to meters) and swim time converter handle common unit conversions.

This section also includes an open water swim pace calculator, swim distance calculator, swim set rest calculator, and swimming calorie calculator for training and calorie tracking.

Triathlon & Endurance Calculators support training and racing across multiple endurance disciplines. Estimate your average triathlon finish time, or use the triathlon training calculator and triathlon nutrition calculator to plan race-day fueling. The MET minutes calculator and Bruce protocol METs calculator quantify exercise intensity, while the fitness age calculator and life expectancy calculator estimate broader health outcomes from activity levels.

This section also includes hiking calorie and hiking time calculators, plus an ERG calculator (rowing) for indoor rowing training.

Weight Management Calculators help you plan and track weight loss or gain over time. Calculate a calorie deficit with the calorie to weight loss converter, or use the intermittent fasting calculator and cheat day calorie calculator to plan eating windows. The body recomposition calculator tracks simultaneous fat loss and muscle gain, while the fat burning zone calculator identifies the heart rate range for maximum fat oxidation.

This section also includes a Weight Watchers points calculator, diet comparison calculator, gastric sleeve weight loss calculator, weight gain calculator, and weight loss calculator for a range of weight management approaches.