Health

Health Calculators

Use transparent screening estimates with clearly stated methods and limitations.

63 tools

A1c Calculator

A1c calculator: estimated average glucose from HbA1c.

Baby Formula Calculator

Baby formula calculator: ounces per feeding from baby weight.

Blood Alcohol Content Calculator

Blood alcohol content (BAC) calculator: Widmark estimate from drinks, weight, and time \u2014 informational only.

Blood Pressure Category Calculator

Blood pressure category calculator: classify a systolic/diastolic reading using the AHA categories.

Blood Sugar Converter

Blood sugar converter: convert glucose between mg/dL and mmol/L instantly.

Body Surface Area Calculator

Body surface area calculator: Mosteller formula from height and weight.

Bra Size Calculator

Bra size calculator: band and cup size from underbust and bust measurements.

Caffeine Half-Life Calculator

Caffeine half-life calculator: how much caffeine remains in your system over time.

Calorie Deficit Calculator

Calorie deficit calculator: weight-loss timeline from daily deficit and target pounds.

Calorie Target Calculator

Calorie target calculator: maintenance, deficit, and surplus targets from weight, height, age, and activity.

Cholesterol Ratio Calculator

Cholesterol ratio calculator: total-to-HDL and LDL-to-HDL ratios from a lipid panel.

Conception Calculator

Conception calculator: conception date and fertility window from due date.

Cycling Calories Calculator

Cycling calories calculator: calories burned cycling by weight and time.

Daily Water Intake Calculator

Daily water intake calculator: estimate hydration needs from body weight and activity.

Fasting Window Calculator

Fasting window calculator: eating window from fast start and length.

Fetal Weight Calculator

Fetal weight calculator: estimated baby weight from ultrasound (Hadlock).

Frame Size Calculator

Frame size calculator: small, medium, or large body frame from wrist.

GFR Calculator

eGFR calculator (CKD-EPI 2021): estimated kidney filtration rate from creatinine, age, and sex.

Gestational Age Calculator

Gestational age calculator: weeks pregnant and due date from last period.

Gym Cost Per Visit Calculator

Gym cost per visit calculator: is your membership actually worth it?

Heart Rate Recovery Calculator

Heart rate recovery calculator: HR drop after exercise.

Heart Rate Zones Calculator

Heart rate zones calculator: target training zones from age and resting heart rate, computed locally.

Intermittent Fasting Calculator

Intermittent fasting calculator: convert between eating windows and fasting hours.

Lean Body Mass Calculator

Lean body mass calculator: LBM from weight and height (Boer).

Macro Split Calculator

Macro split calculator: carbs from calories, protein, and fat targets.

Maintenance Calories Calculator

Maintenance calories calculator: calories to hold your weight (Mifflin-St Jeor).

Mean Arterial Pressure Calculator

Mean arterial pressure calculator: MAP from systolic and diastolic.

Medicine Dosage Calculator

Medicine dosage calculator: dose from body weight and mg/kg dosing instructions.

Menstrual Cycle Calculator

Menstrual cycle calculator: next period and estimated fertile window (private, no tracking stored).

Metabolic Age Calculator

Metabolic age calculator: how your BMR compares to your age group.

Period Cycle Calculator

Period cycle calculator: estimate the next period and fertile window from cycle length.

Pollen Forecast Calculator

Pollen forecast calculator: current pollen levels for any city.

Pregnancy Due Date Calculator

Pregnancy due date calculator: estimate the due date from the first day of the last menstrual period.

Pregnancy Weight Gain Calculator

Pregnancy weight gain calculator: IOM recommended ranges by BMI and week.

Protein Shake Calculator

Protein shake calculator: protein per shake from scoops.

Pulse Pressure Calculator

Pulse pressure calculator: the gap between systolic and diastolic.

Sensitivity Specificity Calculator

Sensitivity and specificity calculator: diagnostic test performance.

Sleep Cycle Calculator

Sleep cycle calculator: find ideal bedtimes that end on a 90-minute sleep cycle for your wake time.

Sleep Cycle Calculator

Sleep cycle calculator: best bedtime to wake refreshed in 90-minute cycles.

Sleep Debt Calculator

Sleep debt calculator: accumulated lost sleep from target hours, actual hours, and days tracked.

Sleep Length Calculator

Sleep length calculator: hours and minutes from sleep cycles, plus when to wake.

Sodium Calculator

Sodium calculator: mg sodium to salt grams and daily value.

Steps to Miles Calculator

Steps to miles calculator: distance walked and calories burned from step count.

Stride Length Calculator

Stride length calculator: stride from height for walking or running.

Sugar in Drinks Calculator

Sugar in drinks calculator: teaspoons and daily value from grams.

Sunscreen SPF Calculator

Sunscreen SPF calculator: burn protection time and reapplication.

Swimming Calories Calculator

Swimming calories calculator: calories burned swimming by weight and time.

UV Exposure Calculator

UV exposure calculator: minutes until sunburn by UV index and Fitzpatrick skin type.

VO2 Max Calculator

VO2 max calculator: estimate aerobic fitness from a 12-minute run or resting heart rate.

VO2 Max Calculator

VO2 max calculator: estimate from a 12-minute Cooper test.

Vitamin D Calculator

Vitamin D calculator: IU to mcg conversion with daily reference.

Waist Hip Ratio Calculator

Waist to hip ratio calculator: WHR and health risk category.

Waist to Height Ratio Calculator

Waist-to-height ratio calculator: assess abdominal obesity risk from waist and height.

Walking Calories Calculator

Walking calories calculator: calories burned walking by weight and time.

Weight Loss Timeline Calculator

Weight loss timeline calculator: how long a healthy weekly deficit will take.

BMI Calculator

Calculate BMI quickly and privately in your browser.

BMR & TDEE Calculator

Estimate adult BMR and TDEE from the Mifflin-St Jeor equation and an explicit activity multiplier.

Body Fat Estimate Calculator

Estimate adult body-fat percentage with the U.S. Navy circumference method and clear limitations.

Calorie Calculator

Estimate daily calories and macros from simple inputs.

Macro Planning Calculator

Allocate a user-selected adult calorie total across configurable protein, fat, and carbohydrate assumptions.

Pregnancy Calculator

Estimate your pregnancy due date and current week from your last period, conception date, or a known due date. Private, no account.

Ideal Weight Calculator

Estimate your ideal body weight using seven common formulas (Hamwi, Devine, Robinson, Miller, Broca, Lorentz, Peterson) plus a healthy BMI range.

Pace Calculator

Calculate your running pace per km or mile from distance and time, plus speed and predicted race times.