Health & Fitness Calculators
Evidence-based health and fitness calculators — BMI, body fat, calories, and more, with clear explanations and cited sources.
Body Composition
BMI, body fat, ideal and healthy weight, and body measurements.
BMI Calculator Body Mass Index with your healthy weight range, shown on a visual scale. Body Fat Calculator Estimate body fat percentage with the U.S. Navy method, plus fat and lean mass. Ideal Weight Calculator Your ideal body weight across five trusted formulas, plus a healthy range. Lean Body Mass Calculator Your lean body mass and fat mass from three formulas — Boer, James, and Hume. Body Surface Area Calculator Your body surface area in m² across eight formulas — used for clinical drug dosing. Waist-to-Hip Ratio Calculator Your waist-to-hip ratio and WHO health-risk band from two quick measurements. Child & Teen BMI Calculator BMI-for-age percentile for children and teens 2–19, using the CDC growth charts. Healthy Weight Calculator The healthy weight range for your height from the WHO BMI band, with a target figure. Height Calculator Predict a child's adult height from the parents' heights, with the likely range. Body Type Calculator Your body shape from four measurements, using the published FFIT classification.
Calories & Metabolism
Daily calories, BMR, and total energy expenditure.
Calorie Calculator Daily calories to maintain, lose, or gain weight — based on your metabolism. BMR Calculator Your Basal Metabolic Rate — the calories your body burns at rest. TDEE Calculator Total Daily Energy Expenditure — how many calories you burn each day. Weight Loss Calculator The daily calories to reach your goal weight, with a projected finish date. Maintenance Calorie Calculator The daily calories that hold your weight steady, at every activity level.
Nutrition & Macros
Macros, protein, carbs, fat, and water intake.
Macro Calculator Your daily protein, carbs, and fat in grams — from your calories and diet plan. Protein Calculator How much protein to eat each day, based on your weight and training goal. Keto Calculator Your keto macros — net carbs, protein by lean mass, and fat — for your goal. Carbohydrate Calculator Your recommended daily carbs in grams, from your calorie needs and goal. Fat Intake Calculator How many grams of dietary fat to aim for each day, based on your calories. Water Intake Calculator Your daily water target in litres, cups, and fluid ounces from your weight.
Fitness & Performance
Running pace, one-rep max, heart-rate zones, and more.
Calories Burned Calculator Calories burned for any activity, from your weight and workout duration. One Rep Max Calculator Estimate your 1RM from a lift, across seven formulas, with a training-load table. Pace Calculator Running pace and speed from your distance and time, plus race finish predictions. Target Heart Rate Calculator Your maximum heart rate and five Karvonen training zones from age and resting HR. Army Body Fat Calculator Body fat by the U.S. Army tape method, checked against AR 600-9 standards. VO2 Max Calculator Estimate your VO2 max from four field tests, with a fitness rating for your age.
Pregnancy & Fertility
Due date, ovulation, periods, conception, and pregnancy weight gain.
Due Date Calculator Your estimated due date from your last period, conception, or IVF transfer, with gestational age. Pregnancy Calculator How far along you are, week by week — with a dated timeline of every milestone. Ovulation Calculator Your fertile window and ovulation day from your last period and cycle length. Period Calculator Forecast your next several periods, plus each cycle’s ovulation and fertile window. Conception Calculator Work back from a due date or last period to your likely conception date and window. Pregnancy Weight Gain Calculator Your recommended pregnancy weight gain by pre-pregnancy BMI, on the IOM 2009 guidelines.
Specialized
Focused specialist tools — alcohol, sleep, and more.