BMI Calculator
Body Mass Index and healthy weight range.
BMR Calculator
Calories burned at rest.
TDEE Calculator
Daily calorie needs by activity.
Body Fat %
U.S. Navy body fat estimate.
Ideal Weight
Healthy target weight for your height.
Lean Body Mass
Estimate your lean tissue mass.
Macro Calculator
Protein, carbs and fat targets.
Calorie Burn
Calories burned during exercise.
Water Intake
Daily hydration needs.
Heart Rate Zones
Training zones from your age.
One Rep Max
Estimate your 1RM strength.
Waist-to-Hip
Body-fat distribution risk.
Reverse BMI
Weight for a target BMI.
Period Calculator
Cycle, ovulation and fertile window.
Free health & fitness calculators
This collection of free health and fitness calculators helps you understand your body and plan your goals — whether you want to lose fat, build muscle, eat better, or train smarter. Every tool works instantly in your browser, supports both metric and imperial units, and uses recognised, science-based formulas.
Where to start
For weight goals, begin with your BMI and body fat percentage, then work out your calorie needs with the BMR and TDEE calculators. Set your nutrition with the macro calculator, and plan training with the heart rate zone and one rep max tools.
Disclaimer: These calculators provide estimates for informational purposes only and do not constitute medical advice. Always consult a qualified healthcare professional before making health decisions.