Free Health Calculators
CDC & NIH Validated
124 health calculators — BMI, calories, TDEE, macros, heart risk, pregnancy, sleep, fitness, and more. All free. No signup. US standard units (lbs & ft-in) by default.
⭐ Most Popular Health Calculators
The calculators Americans search for most — all free, no signup.
BMI Calculator
Body Mass Index with lbs/ft or kg/cm. Healthy weight range.
Calorie Calculator
Daily calories (TDEE) for weight loss, maintenance or gain.
BMR Calculator
Basal Metabolic Rate — calories burned at complete rest.
TDEE Calculator
Total Daily Energy Expenditure by activity level.
Macro Calculator
Protein, carbs, and fat targets for your goal.
Body Fat Calculator
Body fat % using US Navy tape method.
Calorie Deficit Calculator
Daily calorie target for fat loss with macro split.
Sleep Cycle Calculator
Best wake-up times aligned to 90-minute sleep cycles.
Pregnancy Calculator
Week-by-week pregnancy milestones from LMP.
Heart Attack Risk Calculator
10-year ASCVD risk using AHA Pooled Cohort Equations.
Ideal Weight Calculator
Healthy weight range using 5 validated formulas.
Protein Intake Calculator
Daily protein grams for muscle building or fat loss.
Body Composition
12 toolsBMI Calculator
lbs/ft-in or kg/cm with healthy range
Body Fat Calculator
Navy circumference method
Ideal Weight Calculator
5-formula comparison
BMI for Children
CDC pediatric percentiles ages 2-19
Army Body Fat
US Army AR 600-9 tape test
Lean Body Mass
Fat-free mass by 3 formulas
Body Surface Area
Mosteller, DuBois & Haycock
Waist-to-Height Ratio
Better than BMI for metabolic risk
Target Weight Calculator
Goal weight timeline & calorie needs
Body Age Calculator
Biological vs chronological age
Body Recomposition
Lose fat while building muscle
Infant Weight Percentile
WHO 0-24 month growth charts
Calories & Metabolism
10 toolsCalorie Calculator
TDEE for weight loss, gain or maintain
BMR Calculator
Mifflin-St Jeor & Harris-Benedict
TDEE Calculator
Total daily energy by activity level
Calorie Deficit Calculator
Safe deficit for fat loss
Fat Loss Rate Calculator
Realistic weekly fat loss timeline
BMI Calculator
RMR by 3 validated formulas
Muscle Gain Calculator
Max natural monthly muscle gain
Calories Burned
150+ activities via MET values
Calories Burned Walking
By speed, weight & incline
Alcohol Calorie Calculator
Calories in beer, wine & spirits
Macros & Nutrition
17 toolsMacro Calculator
Protein, carbs & fat by goal
Protein Intake Calculator
Daily protein grams by goal
Keto Macro Calculator
Fat, protein & net carb targets
Protein Per Meal
Optimal protein dose per sitting
Water Intake Calculator
Daily hydration goal in oz & liters
Fiber Intake Calculator
Soluble & insoluble fiber needs
Glycemic Load Calculator
GL & GI of foods for blood sugar
Sugar Intake Calculator
Added sugar vs AHA guidelines
Sodium Intake Calculator
Daily sodium limit by health status
Vitamin D Calculator
Deficiency risk & supplement dose
Vitamin C Calculator
Daily needs & immune dosing
Magnesium Calculator
RDA by age, sex & supplement form
Calcium Calculator
Bone health calcium requirements
Iron Intake Calculator
Iron RDA, deficiency & absorption
Omega-3 Calculator
EPA & DHA dose for heart & brain
Zinc Calculator
Daily zinc for immune & skin health
Creatine Dosage
Loading & maintenance by weight
Fitness & Exercise
21 toolsHeart Rate Calculator
Max HR, fat burn & training zones
VO2 Max Calculator
From Cooper test or resting HR
One Rep Max Calculator
Epley, Brzycki & Lander formulas
HIIT Calculator
Tabata, 30-20-10 & custom intervals
Running Pace Calculator
Pace, speed & race time predictions
Pace Calculator
5K, 10K, half & full marathon
Marathon Training
Race pace & weekly mileage plan
Squat Calculator
Strength standards & percentages
Push-Up Calculator
Fitness norms by age & sex
Pull-Up Calculator
Standards & training progression
Plank Time Calculator
Core endurance norms & program
Steps Calculator
Steps to distance, calories & activity
Steps to Calories
Accurate by weight & pace
Cycling Calories
Indoor & outdoor by speed & terrain
Swimming Calories
By stroke, pace & body weight
Grip Strength Calculator
Longevity & health percentile
Athletic Performance
Strength, speed & endurance score
Sprint Calculator
Sprint training paces & zones
Injury Recovery
Return-to-sport timeline
Flexibility Calculator
Range of motion norms by age
Sit and Reach
Hamstring flexibility scoring
Heart & Cardiovascular
11 toolsHeart Attack Risk
10-yr ASCVD Pooled Cohort Equations
Blood Pressure Calculator
AHA 2017 hypertension categories
Cholesterol Calculator
LDL, HDL ratio & cardiovascular risk
Heart Age Calculator
Cardiovascular age vs chronological
Stroke Risk Calculator
Framingham + CHA2DS2-VASc
Diabetes Risk Calculator
FINDRISC 10-year type 2 risk
BAC Calculator
Blood alcohol by weight & drinks
Kidney Function
eGFR with CKD-EPI & Cockcroft-Gault
Liver Health Calculator
NAFLD risk assessment
Thyroid Calculator
Hypo & hyperthyroid risk
Inflammation Risk
Dietary Inflammatory Index
Women's Health
9 toolsPregnancy Calculator
Week-by-week milestones from LMP
Due Date Calculator
EDD from LMP, conception or IVF
Ovulation Calculator
5-day fertile window from cycle length
Menstrual Cycle Calculator
Period, ovulation & PMS dates
Pregnancy Weight Gain
IOM guidelines by pre-pregnancy BMI
Pregnancy Nutrition
Calories & nutrients by trimester
Pregnancy Conception
Estimate conception date from due date
Breastfeeding Calories
Extra calorie needs while nursing
Menopause Symptoms
Greene Climacteric Scale scoring
Sleep & Wellness
15 toolsSleep Cycle Calculator
Best wake time via 90-min cycles
Sleep Need Calculator
Sleep requirement by age & activity
Caffeine Half-Life
When caffeine clears for better sleep
Blue Light Exposure
Screen time & melatonin impact
Stress Level Calculator
PSS-10 & Holmes-Rahe stress score
Cortisol Stress Calculator
Lifestyle impact on stress hormones
Meditation Benefits
Health impact of daily practice
Mental Health Score
PHQ-9 & GAD-7 wellness screening
Longevity Calculator
Life expectancy by lifestyle factors
Body Age Calculator
Biological vs chronological age
Age Calculator
Exact age in years, months, days
Intermittent Fasting
16:8, 18:6, OMAD & 5:2 protocols
Fasting Window
Eating window start & end times
Gut Health Calculator
Microbiome health assessment
Immune Health
Immune system strength score
Hydration & Environment
9 toolsWater Intake Calculator
Daily water goal in oz & liters
Hydration Calculator
Exercise fluid needs & strategy
Dehydration Calculator
Fluid deficit & rehydration guide
Sweat Rate Calculator
Personalized exercise sweat loss
UV Exposure Calculator
Safe sun time & vitamin D synthesis
Air Quality Health
AQI health risk by activity
Sauna Benefits
Health impact by frequency & temp
Cold Exposure
Safe cold plunge duration & temp
Cold Shower Benefits
Mood, energy & recovery impact
Substance & Recovery
6 toolsBAC Calculator
Blood alcohol by weight & drinks
Alcohol Metabolism
How long until sober calculator
Alcohol Calorie Calculator
Calories in beer, wine & cocktails
Hangover Recovery
Recovery time & evidence-based tips
Caffeine Half-Life
Caffeine clearance & sleep cutoff
Nicotine Withdrawal
Symptom timeline & cessation tips
Ergonomics & Posture
6 toolsErgonomics Score
Workstation RSI & back pain risk
Standing Desk Calculator
Optimal sit-stand ratio & height
Posture Calculator
Postural deviation & correction plan
Eye Health Calculator
Digital eye strain & dry eye risk
Hearing Age Calculator
Audiological age from noise exposure
Altitude Sickness
AMS risk for hikers & climbers
About Our Free Health Calculators
FinanceCalculator.com provides 124 free health calculators grounded in peer-reviewed research and guidelines from the Centers for Disease Control and Prevention (CDC), National Institutes of Health (NIH),American Heart Association (AHA), and American College of Sports Medicine (ACSM). Every tool defaults to US standard units — pounds for weight, feet and inches for height — with a metric toggle available on every calculator.
Our BMI Calculator uses the CDC standard formula with separate categories for adults and children. The Calorie Calculator uses the Mifflin-St Jeor equation, validated as the most accurate TDEE formula for the general US population. The Heart Attack Risk Calculator uses the AHA/ACC Pooled Cohort Equations, the standard tool for ASCVD risk estimation.
All calculations run entirely in your browser. No personal health data is sent to any server, stored in any database, or shared with any third party. This privacy-first design is essential for sensitive health information. Results are for educational and informational purposes — always consult a licensed healthcare provider for medical decisions.
What units do these calculators use?
All calculators default to US standard units — lbs for weight, feet and inches for height. Every calculator has a toggle to switch to metric (kg/cm).
Are these calculators medically accurate?
Yes. All use peer-reviewed formulas from CDC, NIH, AHA, and ACSM. Results are population-level estimates; consult your doctor for personal medical advice.
Do I need to create an account?
No signup, registration, or payment is ever required. All 124 calculators are permanently free and fully functional without an account.
Do these calculators work on iPhone?
Yes. All calculators are fully responsive and tested on iPhone, Android, iPad, and all major desktop browsers. No app download needed.
All health calculators use CDC, NIH, AHA, and ACSM validated formulas. Results are educational estimates and should not replace professional medical advice. Always consult a licensed healthcare provider before making health decisions.