Health calculators
100 free tools. Search by what you want to do, or browse by category.
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BMI Calculator
Body mass index from height and weight, with your healthy weight range.
Body Fat Calculator (US Navy)
Estimate body fat percentage from tape measurements.
Ideal Weight Calculator
Compare ideal weight from four classic formulas.
Lean Body Mass Calculator
Split your weight into lean mass and fat mass.
Waist-to-Hip Ratio Calculator
Check where your body stores fat and the related health risk.
Waist-to-Height Ratio Calculator
A simple rule: keep your waist under half your height.
Body Surface Area Calculator
BSA by Mosteller, DuBois and Haycock formulas.
Body Roundness Index Calculator
A shape-based index of visceral fat from waist and height.
BMI Prime & Ponderal Index
How far your BMI sits from the upper healthy limit of 25.
Body Frame Size Calculator
Small, medium or large frame from height and wrist size.
BMR Calculator
Calories your body burns at complete rest.
TDEE & Daily Calorie Calculator
Total daily energy expenditure at each activity level.
Weight Loss Timeline Calculator
How long to reach a goal weight at your calorie intake.
Macro Calculator
Protein, carb and fat grams for your calorie target.
Protein Intake Calculator
Daily protein range for your weight and goal.
Fiber Intake Calculator
Your daily fiber goal and how your intake compares.
Sodium Intake Calculator
Add up sodium across meals and compare with limits.
Added Sugar Limit Calculator
Compare your sugar intake with WHO and AHA limits.
Meal Calorie Planner
Divide daily calories across your meals and snacks.
Weight Gain Calculator
Calories and timeline to gain weight steadily.
Target Heart Rate Calculator
Heart rate training zones using the Karvonen method.
Max Heart Rate Calculator
Maximum heart rate from several published formulas.
VO2 Max Calculator
Estimate aerobic fitness from the Cooper 12-minute run.
One-Rep Max Calculator
Estimate your max lift from a lighter set.
Calories Burned Running Calculator
Calories burned for a run of any distance.
Steps to Calories Calculator
Convert your daily steps to distance and calories.
Running Pace & Race Predictor
Pace per km and mile plus predicted race times.
Cycling Calories Calculator
Calories burned cycling by speed and time.
Calories Burned by Activity
Compare calories burned across ten activities.
Heart Rate Recovery Calculator
How quickly your pulse drops one minute after exercise.
Blood Pressure Category Calculator
See which ACC/AHA blood pressure category you fall in.
Mean Arterial Pressure Calculator
Average pressure that perfuses your organs.
Pulse Pressure Calculator
The gap between your top and bottom blood pressure numbers.
Cholesterol Ratio Calculator
Total-to-HDL ratio as a heart risk indicator.
LDL Cholesterol Calculator
Estimate LDL from a standard lipid panel (Friedewald).
Non-HDL Cholesterol Calculator
All the cholesterol carried by harmful particles.
Triglyceride-to-HDL Ratio Calculator
A quick marker of insulin resistance and heart risk.
Corrected QT (QTc) Calculator
Correct the ECG QT interval for heart rate.
Cardiac Output Calculator
Blood pumped per minute and cardiac index.
Rate Pressure Product Calculator
Heart workload from pulse and systolic pressure.
A1C to Average Glucose Calculator
Convert HbA1c to estimated average glucose.
Average Glucose to A1C Calculator
Estimate HbA1c from average glucose readings.
Blood Glucose Converter & Checker
Convert mg/dL and mmol/L and check fasting levels.
HOMA-IR Calculator
Insulin resistance estimated from fasting glucose and insulin.
QUICKI Insulin Sensitivity Calculator
Insulin sensitivity index from fasting labs.
Insulin-to-Carb Ratio Calculator
Educational estimate of meal and correction insulin.
Total Daily Insulin Estimator
Typical basal and bolus split, for education.
Glycemic Load Calculator
How much a food portion raises blood sugar.
Type 2 Diabetes Risk Score
ADA-style risk points from lifestyle and history.
Time in Range & GMI Calculator
CGM time in range and glucose management indicator.
Pregnancy Due Date Calculator
Estimated due date from your last period.
Conception Date Calculator
Work backwards from a due date to when you conceived.
Ovulation & Fertile Window Calculator
Predict ovulation day and your most fertile days.
Gestational Age Calculator
Weeks and days pregnant on any date.
Pregnancy Weight Gain Calculator
Recommended weight gain by week using IOM guidance.
Pregnancy Calorie Calculator
Extra daily calories needed by trimester.
Menstrual Cycle Length Calculator
Average cycle length, regularity and next period.
IVF Due Date Calculator
Due date from your embryo transfer date.
Breastfeeding Calorie Calculator
Calories and fluids needed while nursing.
Osteoporosis Self-Assessment (OST)
Simple bone density screening score for women.
Child Adult Height Predictor
Mid-parental height estimate for your child.
Children’s Acetaminophen Dose Calculator
Weight-based paracetamol dose for fever or pain.
Children’s Ibuprofen Dose Calculator
Weight-based ibuprofen dose for children over 6 months.
Baby Formula Feeding Calculator
How much milk your baby needs each day.
Pediatric Maintenance Fluids Calculator
Daily fluid needs by weight (Holliday-Segar).
Child Calorie Needs Calculator
Daily energy needs for ages 3–18.
Child Sleep Needs Calculator
Recommended sleep for your child’s age.
Kids Screen Time Calculator
Compare weekly screen time with age guidelines.
Baby Corrected Age Calculator
Adjusted age for babies born early.
Kids Water Intake Calculator
Daily fluid needs for children and teens.
Bedtime Calculator
Best bedtimes to wake up between 90-minute sleep cycles.
Wake-Up Time Calculator
When to set your alarm if you go to bed now.
Sleep Debt Calculator
Total sleep shortfall over the last seven nights.
Caffeine Cutoff Calculator
Last time to drink coffee without hurting sleep.
Stress Level Check
An informal 8-question check of recent stress.
PHQ-9 Depression Screening
The standard nine-question depression screening tool.
GAD-7 Anxiety Screening
The standard seven-question anxiety screening tool.
Burnout Check
An informal six-question check for work burnout.
Chronotype Calculator
Are you a morning lark or night owl? Uses mid-sleep time.
Nap Planner
Best time and length for a nap that will not wreck tonight’s sleep.
Water Intake Calculator
Daily water needs for your weight, exercise and climate.
Alcohol Units & Calories Calculator
Weekly alcohol units and calories from your drinks.
Blood Alcohol Content Estimator
Rough BAC estimate and time to sober, using Widmark.
Daily Caffeine Intake Calculator
Add up caffeine from coffee, tea, soda and energy drinks.
Smoking Cost & Savings Calculator
What smoking costs and what you save by quitting.
Sun Exposure & SPF Calculator
Estimated time to burn with and without sunscreen.
Daily Step Goal Planner
Build up your steps gradually toward a goal.
Sitting Time Calculator
How much of your waking day you spend sitting.
Alcohol-Free Savings Calculator
Money, calories and units avoided since you stopped.
Habit Formation Calculator
How far along you are toward making a habit automatic.
eGFR Kidney Function Calculator
Kidney filtration rate using CKD-EPI 2021.
Creatinine Clearance Calculator
Cockcroft-Gault estimate used for drug dosing.
Anion Gap Calculator
Serum anion gap, corrected for albumin.
Corrected Calcium Calculator
Calcium adjusted for low albumin.
Corrected Sodium Calculator
Sodium adjusted for high blood glucose.
BUN-to-Creatinine Ratio Calculator
Helps tell dehydration from kidney problems.
Serum Osmolality Calculator
Blood concentration from sodium, glucose and BUN.
Body Temperature & Fever Checker
Convert °C and °F and see if it counts as a fever.
Age Calculator
Exact age in years, months and days, plus next birthday.
Pack-Years Calculator
Smoking history and lung cancer screening eligibility.
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