Free Online Health & Fitness Calculators

Whether you're trying to lose weight, build muscle, train for a race, or just figure out what "healthy" actually looks like for your body — we've got the tools to help. Our health and fitness calculators were built for everyday people, athletes, and anyone who wants real answers without wading through conflicting advice online. Need to know your BMI, daily calorie needs, or ideal macros for your goals? Trying to figure out your target heart rate zones or how long it'll take to reach your goal weight? We've got you covered. From body fat percentage and VO2 max to nutrition planning and workout metrics, every calculator gives you accurate results based on your actual numbers. Stop guessing — plug in your stats and get a clear picture of where you stand and where you're headed.

BMI & Body Composition Calculators

25 tools

Blood & Substance Calculators

12 tools

Body Measurements Calculators

14 tools

Calories & Energy Calculators

13 tools

Calories Burned Calculators

23 tools

Cardiovascular Clinical Calculators

33 tools

Cholesterol & Metabolic Calculators

9 tools

Cycling Calculators

11 tools

Diabetes & Blood Sugar Calculators

10 tools

Heart Rate & Cardiovascular Calculators

18 tools

Hormones & Endocrine Calculators

4 tools

Hydration Calculators

4 tools

Ideal Weight Calculators

6 tools

Kidney & Renal Calculators

8 tools

Liver & GI Calculators

7 tools

Macronutrients & Diet Calculators

20 tools

Mental Health & Wellness Calculators

7 tools

Military Fitness Calculators

4 tools

Miscellaneous Health Calculators

14 tools

Pediatric Health Calculators

10 tools

Pharmacology & Dosing Calculators

11 tools

Pregnancy & Fertility Calculators

34 tools

Respiratory Calculators

8 tools

Running & Jogging Calculators

18 tools

Skin & Dermatology Calculators

5 tools

Sleep Calculators

9 tools

Sports Statistics Calculators

23 tools

Sports-Specific Calculators

13 tools

Strength Training Calculators

17 tools

Swimming Calculators

4 tools

Triathlon & Endurance Calculators

10 tools

Weight Management Calculators

10 tools