Free health calculators
Free health calculators that actually help
Evidence-based tools for calories, BMI, TDEE, macros, hydration and more — plus the science behind every number.
Featured calculators
BMI Calculator
Calculate your Body Mass Index and see whether you are underweight, normal weight, overweight or obese.
Calories Calculator
How many calories should you eat per day for weight loss, maintenance or muscle gain — based on Mifflin-St Jeor.
TDEE Calculator
Calculate your Total Daily Energy Expenditure — the total calories your body burns each day.
Macro Calculator
Get your protein, carb and fat macros for cutting, bulking, maintenance, keto or low-carb diets.
Popular tools
View all →Macro Calculator
Get your protein, carb and fat macros for cutting, bulking, maintenance, keto or low-carb diets.
Protein Calculator
How many grams of protein you need each day for fat loss, muscle gain, endurance or maintenance.
BMR Calculator
Calculate your Basal Metabolic Rate — the calories your body burns at complete rest.
TDEE Calculator
Calculate your Total Daily Energy Expenditure — the total calories your body burns each day.
BMI Calculator
Calculate your Body Mass Index and see whether you are underweight, normal weight, overweight or obese.
Calories Calculator
How many calories should you eat per day for weight loss, maintenance or muscle gain — based on Mifflin-St Jeor.
Water Intake Calculator
How much water should you drink per day? Personalized result in ml, liters and cups.
Ideal Weight Calculator
Estimate your ideal body weight using Devine, Robinson, Miller and Hamwi formulas.
Latest articles
All articles →How Many Calories Should You Eat Per Day?
Wondering how many calories you should eat per day? Learn how age, gender, weight, activity level, and fitness goals affect your daily calorie needs. Use this guide to calculate maintenance calories, lose weight, gain muscle, and improve your overall health.
6 min read
How Many Calories Should I Eat to Lose Weight?
A 500-calorie daily deficit will typically lose you about 1 pound (0.45 kg) of body fat per week. Here is how to find your number.
4 min read
BMI Chart for Adults: Healthy Weight by Height
A simple BMI reference: healthy weight range in kilograms and pounds for every common height.
3 min read
How Much Protein Do You Actually Need?
For most active adults, 1.6-2.2 g of protein per kilogram of body weight is the sweet spot. Here is how to find your number.
5 min read
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