Health & Fitness
Health & Fitness Calculators
15 free calculators
Evidence-based health and fitness calculators — find your BMI and healthy weight range, estimate daily calorie needs with BMR and TDEE, plan a macro split, check body fat and waist-to-hip ratio, and track water intake or a pregnancy due date. Nothing is stored; every calculation happens on your device.
BMI
Calculate your Body Mass Index in seconds. Enter height and weight in metric (kg/cm) or imperial (lbs/ft·in) units to see your BMI score, weight category, and the healthy weight range for your exact height.
BMR
Find out how many calories your body burns at rest (BMR) and how many you need daily based on your activity level (TDEE). Get personalised calorie targets to lose, maintain, or gain weight.
Body Fat
Calculate your body fat percentage using the US Navy method. Get fat mass, lean mass, and your fitness category — no equipment needed.
Body Frame
Determine whether you have a small, medium or large body frame from your height and wrist size — the missing piece when interpreting ideal-weight ranges.
Calorie Deficit
Work out how many calories to eat each day to lose weight, your weekly rate of loss, and how many weeks it will take to reach your goal — with a safe, sustainable deficit.
Calories
Calculate your daily calorie needs (TDEE) and get personalized targets for weight loss, maintenance, or muscle gain based on your activity level.
Due Date
Calculate your pregnancy due date, current week, trimester, and key milestones using your last menstrual period (LMP) or conception date.
Heart Rate Zones
Find your personal heart-rate training zones — warm-up, fat-burn, cardio, anaerobic and peak — from your age, with the Karvonen method if you add your resting heart rate.
Ideal Weight
Find your ideal body weight using four clinically validated formulas — Hamwi, Devine, Robinson, and Miller. Enter your height and gender to get a recommended weight range and see how the formulas compare.
Macro Split
Turn your daily calorie target into grams of protein, carbs and fat using a diet style — balanced, low-carb, high-protein or keto — with a visual macro breakdown.
Pregnancy Weight
See your recommended pregnancy weight gain for the current week, based on your pre-pregnancy BMI and Institute of Medicine (IOM) guidelines — and check whether you are on track.
TDEE
Find your Total Daily Energy Expenditure (TDEE) — the calories you burn each day — from your BMR and activity level, plus calorie targets to lose, maintain or gain weight.
Waist-to-Height
Find your waist-to-height ratio — often a better health-risk indicator than BMI. The simple rule: keep your waist under half your height (ratio below 0.5).
Water Intake
Calculate your recommended daily water intake based on your body weight, activity level, and climate. Get targets in litres and glasses.
WHR
Calculate your waist-to-hip ratio (WHR) and assess your cardiovascular and metabolic disease risk based on WHO guidelines.