Health & Body
48 free online calculators — instant results, no sign-up
HOTBMI CalculatorBody mass index with healthy range by standardBody Fat CalculatorCircumference-based estimate with ACE classificationWaist-to-Hip Ratio CalculatorWHR with abdominal obesity risk referenceBMR CalculatorBasal metabolic rate — Mifflin & Harris-Benedict equationsTDEE CalculatorTotal daily energy expenditure by activity levelIdeal Weight CalculatorDevine, Robinson and Miller formulasPregnancy Due Date CalculatorDue date, gestational week and trimestersWater Intake CalculatorRecommended daily water by weight and activityHeart Rate Zone CalculatorMax heart rate and training intensity zonesNEWBody Surface Area CalculatorFive BSA formulas with 1.73m² referenceNEWPregnancy Weight Gain CalculatorRecommended gain vs actual — IOM guidelinesNEWSleep CalculatorSleep duration, bedtime and wake-up planningNEWDaily Calorie CalculatorCalorie needs from BMR and activity factorNEWRunning Pace CalculatorPace per km/mile, speed and finish timeOvulation CalculatorOvulation day and fertile window from cycle lengthRace Finish Time Predictor5K/10K/half/full marathon — Riegel formulaOne Rep Max CalculatorEpley & Brzycki formulas with training weight tableBAC CalculatorBlood alcohol estimate, legal limits and sobering timeMacro CalculatorProtein, carbs and fat grams by goal-based ratioChild Height PredictorTarget adult height from parents with expected rangeBlood Pressure CalculatorBP category, pulse pressure and reference tablesCaffeine Intake CalculatorTotal caffeine from drinks vs the 400mg daily limitSmoking Cost CalculatorMoney burned, opportunity cost and health ledgerProtein Intake CalculatorDaily protein needs by weight and goal, food equivalentsSteps to Calories CalculatorSteps to distance, calories burned and walking timeVO2 Max CalculatorCooper 12-min run and resting-HR aerobic fitness estimateFFMI CalculatorFat-free mass index with natural muscle limit ratingLean Body Mass CalculatorBoer & James formulas for lean mass and fat massWaist-to-Height Ratio CalculatorWaist ÷ height — central obesity gradingPeriod & Ovulation CalculatorCycle prediction, ovulation day and fertile windowBlood Type Inheritance CalculatorParent blood types → child blood type oddsKids Fever Medicine DosageWeight-based ibuprofen and acetaminophen dosingBaby Milk Intake CalculatorDaily milk volume and feeding frequency by agePregnancy Week CalculatorGestational age, due date and trimester milestoneseGFR CalculatorCKD-EPI 2021 equation, CKD stagingExercise Calorie CalculatorMET-based burn for 40+ activitiesWeight Loss Time Calculator7700 kcal rule, deficit projectionBaby Vaccine ScheduleChina national immunization dates plannerCreatinine Clearance CalculatorCockcroft-Gault, kidney stagingIntermittent Fasting Calculator16:8/18:6/20:4 eating windowsRace Time PredictorRiegel formula, all distancesBody Water CalculatorWatson formula, water percentageBlood Glucose Convertermmol/L ↔ mg/dL, HbA1c → eAG, verdictsSafe Period CalculatorCalendar method, fertile window, 3-cycle tableChild Growth StandardsWHO 0-5y weight/height percentilesCholesterol CalculatorFriedewald LDL + lipid gradingBody Age Calculator8 lifestyle factors · biological ageFTP Calculator (Cycling)20min x0.95 · W/kg level · power zones