Health & Fitness Calculators

Calculate your Body Mass Index from height and weight, and see which BMI category you fall into. Supports metric and imperial units.

Estimate your daily calorie needs (TDEE) based on your BMR and activity level, plus targets for losing or gaining weight.

Estimate your ovulation date, fertile window and next period from your last period and average cycle length.

Estimate your one-rep max for any lift from the weight and reps you completed, using proven strength formulas.

Calculate your daily protein, carb and fat targets (macros) based on your calorie goal and chosen split.

Calculate body surface area using the Du Bois and Mosteller formulas — the standard for medical dosing.

Estimate your body fat percentage using the U.S. Navy method from a few simple tape measurements.

Calculate your running pace, finish time or distance — perfect for planning a 5K, 10K, half or full marathon.

Calculate your Basal Metabolic Rate — the calories your body burns at rest — using the Mifflin-St Jeor equation.

Estimate your baby's due date from your last menstrual period (LMP) using Naegele's rule.

Estimate calories burned for walking, running, cycling, lifting and more — based on MET values, your weight and duration.

Estimate how much water you should drink each day based on your body weight and activity.

Find your ideal body weight range based on height and gender using established medical formulas.

Estimate your lean body mass (everything except fat) using the Boer formula from height, weight and gender.

Find your daily protein target in grams, based on your body weight and goal — maintenance, muscle gain or fat loss.

Convert an HbA1c percentage into estimated average glucose (eAG) in mg/dL and mmol/L.

Calculate your waist-to-hip ratio and see your health-risk band per WHO guidance.

Calculate your five training heart-rate zones from your age — recovery to max effort — for smarter cardio.