No calculators match your search. Clear filter
All health calculators are free, require no sign-up, and use validated formulas from medical and research sources. Results include explanations, reference tables, and actionable guidance.
Body Composition
BMI Calculator
Body Mass Index with WHO categories and healthy weight range
Body Fat Calculator
Estimate body fat % using Navy, BMI, and skinfold methods
Lean Body Mass Calculator
LBM using Boer, James, Hume, and Peters formulas
Waist-to-Hip Ratio Calculator
WHR with WHO cardiovascular risk classification
Waist-to-Height Ratio Calculator
WHtR with health risk thresholds — simpler than BMI
Body Surface Area Calculator
BSA using 6 formulas including Mosteller and DuBois
Frame Size Calculator
Wrist method to determine small, medium, or large frame
Ideal Weight Calculator
Ideal weight using Devine, Hamwi, Robinson, and Miller formulas
Child BMI Calculator
BMI-for-age percentile for children 2–20 using CDC charts
Height Predictor Calculator
Predict child's adult height from parents' heights
Calorie & Nutrition
Calorie Calculator (TDEE)
Total daily energy expenditure with activity multipliers
BMR Calculator
Basal metabolic rate using 5 validated formulas
Macro Calculator
Personalized protein, carb, and fat targets for your goal
Resting Metabolic Rate Calculator
RMR using Mifflin, Harris-Benedict, Schofield, and more
Water Intake Calculator
Daily hydration needs based on weight and activity
Keto Macro Calculator
Fat, protein, and net carbs for ketogenic diet variants
Fiber Intake Calculator
Daily fiber targets by age, sex, and calorie level
Vitamin D Calculator
Deficiency risk and supplement dose by sun exposure and skin tone
Intermittent Fasting Calculator
Eating windows for 16:8, 18:6, 20:4, 5:2, and OMAD
Carb Cycling Calculator
High, medium, and low carb day macros by training schedule
Fitness & Exercise
Calories Burned Calculator
40+ activities using MET values from Compendium of PA
Calories Burned Walking
Walking calories by speed, distance, weight, and terrain
Calories Burned Running
Running calories with 5K to marathon race estimates
Workout Calorie Calculator
Calories burned in strength, HIIT, yoga, cycling, and more
Running Pace Calculator
Find pace, time, or distance with race projection table
Pace Converter
Convert min/mile ↔ min/km ↔ mph ↔ kph instantly
Steps to Miles Calculator
Personalized by stride length with calorie estimates
One Rep Max (1RM) Calculator
Estimate max strength from reps using 7 formulas
VO2 Max Calculator
Aerobic fitness via Cooper test, Rockport walk, and HR methods
Push-Up Test Calculator
ACSM fitness rating by age and sex with training plan
Heart & Cardiovascular
Heart Rate Calculator
Max HR formulas, RHR classification, and recovery score
Target Heart Rate Calculator
Karvonen 5-zone training table for fat burn to max effort
Heart Rate Zones Calculator
Visual zone chart with polarized, pyramidal, and HIIT models
Blood Pressure Calculator
AHA 2017 categories, MAP, pulse pressure with guidance
Cholesterol Ratio Calculator
7 lipid panel ratios including Total/HDL and LDL/HDL
Sleep, Wellness & Lifestyle
Sleep Calculator
Optimal bedtime and wake time based on 90-min sleep cycles
Age Calculator
Exact age in years, months, days, hours with milestone table
BAC Calculator
Widmark formula with impairment levels and legal limits
Smoking Cost Calculator
Lifetime savings with investment growth and health timeline
Life Expectancy Calculator
Estimate lifespan based on lifestyle factors and actuarial data
Women's Health & Pregnancy
Pregnancy Due Date Calculator
EDD from LMP, conception date, or IVF transfer with milestones
Ovulation Calculator
Ovulation date and fertile window with 3-cycle forecast
Menstrual Cycle Calculator
4-phase cycle breakdown with 6-period forecast
Conception Date Calculator
Reverse-calculate conception window from due date or LMP
Weeks Pregnant Calculator
Current week, trimester, progress bar, and development notes
Fertility Window Calculator
Best days to conceive with 3-cycle forecast and probability table
Pregnancy Weight Gain Calculator
IOM 2009 recommendations by pre-pregnancy BMI with trimester tracking