Health and Weight Calculator

This health and weight calculator provides essential metrics to help you understand your body composition and energy needs. Calculate your Body Mass Index (BMI), Basal Metabolic Rate (BMR), and Total Daily Energy Expenditure (TDEE) using our simple tools.

BMI Calculator

The Body Mass Index (BMI) is a simple calculation that relates weight to height. It's commonly used to classify underweight, normal weight, overweight, and obesity in adults.

BMI Formula

BMI = Weight (kg) / (Height (m) × Height (m))

For US units: BMI = (Weight (lbs) / (Height (in) × Height (in))) × 703

BMI Category	BMI Range
Underweight	Below 18.5
Normal weight	18.5 - 24.9
Overweight	25 - 29.9
Obesity	30 and above

BMI is a screening tool, not a diagnostic tool. It doesn't distinguish between muscle, bone, and fat, and may not be accurate for athletes or very short/very tall individuals.

BMR Calculator

The Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic functions like breathing, circulation, and cell production while at complete rest.

BMR Formula (Mifflin-St Jeor Equation)

For men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) + 5

For women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) - 161

BMR calculations are useful for understanding your body's calorie needs at rest. This is the foundation for calculating your Total Daily Energy Expenditure (TDEE).

TDEE Calculator

The Total Daily Energy Expenditure (TDEE) estimates the total number of calories you burn each day, including activity and digestion.

TDEE Formula

TDEE = BMR × Activity Factor

Activity factors:

Sedentary (little or no exercise): 1.2
Lightly active (light exercise/sports 1-3 days/week): 1.375
Moderately active (moderate exercise/sports 3-5 days/week): 1.55
Very active (hard exercise/sports 6-7 days a week): 1.725
Extra active (very hard exercise/physical job & exercise 2x/day): 1.9

Understanding your TDEE helps determine how many calories you need to maintain, lose, or gain weight.

How to Use These Calculators

Enter your weight in the appropriate units (kg or lbs).
Enter your height in the appropriate units (cm or inches).
For BMR and TDEE calculations, enter your age and select your gender.
For TDEE, select your activity level from the dropdown menu.
Click "Calculate" to see your results.
Review the interpretation of your results in the next section.

How to Interpret Results

BMI Interpretation

Your BMI category provides a general idea of your weight status. Remember that BMI doesn't account for muscle mass, bone density, or overall body composition.

BMR Interpretation

Your BMR represents the calories your body needs to maintain basic functions at rest. This is the foundation for calculating your daily calorie needs.

TDEE Interpretation

Your TDEE shows the total calories you burn each day, including activity and digestion. This helps determine how many calories you need to maintain, lose, or gain weight.

Example Calculation

For a 30-year-old woman who weighs 68 kg, is 165 cm tall, and is moderately active:

BMI: 25.0 (Overweight)
BMR: 1,450 calories/day
TDEE: 2,232 calories/day

Frequently Asked Questions

Is BMI an accurate measure of body fat?

No, BMI is a screening tool that doesn't distinguish between muscle, bone, and fat. It may not be accurate for athletes or very short/very tall individuals.

How often should I recalculate my BMR and TDEE?

You should recalculate these metrics when your weight, height, age, or activity level changes significantly.

Can I use these calculators for children?

These calculators are designed for adults. For children, you would need specialized pediatric formulas.

What should I do if my BMI is in the overweight or obese range?

Consult with a healthcare provider for personalized advice. They can help you create a safe and sustainable weight loss plan.