Health Calculators

BMI Calculator

Enter your height and weight to get your BMI and category (underweight, normal, overweight, or obese). BMI is a screening tool used by the CDC to estimate weight-related health risk for the general adult population.

Body Fat Calculator

Enter your height, neck, and waist measurements (plus hips if female) to instantly see your estimated body fat percentage and category.

Ideal Weight Calculator

Enter your height and sex to see your ideal weight range from three validated formulas (Devine, Robinson, Miller) in both lbs and kg.

Lean Body Mass Calculator

Enter weight, height, and gender to calculate lean body mass and estimated body fat percentage.

Waist-to-Hip Ratio Calculator

Enter waist and hip measurements to calculate your waist-to-hip ratio and health risk level.

TDEE Calculator

Enter your stats and activity level to instantly see how many calories you need per day to maintain your weight — plus targets for losing or gaining.

BMR Calculator

Enter your sex, age, height, and weight to see your BMR — how many calories you burn at rest before any activity.

Calorie Deficit Calculator

Enter your maintenance calories, daily intake target, and weight goals to see your weekly loss rate and estimated goal date.

Water Intake Calculator

Enter your weight, activity level, and climate to see your personalized daily water intake recommendation in ounces, cups, and liters.

Ovulation Calculator

Enter your last period date and cycle length to see your estimated ovulation date and the 6-day fertile window when conception is most likely.

Pediatric Medication Dose Calculator — Tylenol & Motrin

Enter the child's weight in kg and the medication concentration. Get the exact dose in mg and mL.

Drug Half-Life Clearance Calculator — How Long Until It Clears?

Enter the dose, half-life, and hours since dose. See remaining amount, percentage left, and total clearance time.

Blood Alcohol Content (BAC) Calculator

Enter drinks, weight, gender, and hours elapsed to estimate BAC and time to sobriety.

Sleep Cycle Calculator

Enter your wake time or bedtime to find the optimal sleep times based on 90-minute sleep cycles.

Sleep Debt Calculator — How Tired Are You Really?

Enter hours slept each night for the last week. See total debt, average, and how many days to recover.

Pregnancy Due Date Calculator

Enter the first day of your last menstrual period (LMP) to instantly see your estimated due date, gestational age, trimester, and estimated conception date.

Calories Burned Walking Calculator

Enter your weight, walking pace, and duration to instantly see how many calories you burn.

Heart Rate Zone Calculator

Enter age and resting heart rate to calculate your 5 heart rate training zones.

Calories Burned Running Calculator

Enter weight, distance, and pace to calculate calories burned running.

Pregnancy Weight Gain Calculator

Enter pre-pregnancy BMI, current weight, and weeks pregnant to check if your weight gain is on track.