How to Use the Calculator

Step 1: Select Your Measurement System

Choose between:

• Metric system (centimeters and kilograms)
• Imperial system (inches and pounds)

Toggle between systems using the buttons at the top of the calculator.

Step 2: Enter Your Personal Information

Provide accurate details for precise results:

• Age: Metabolism changes as we age
• Sex: Biological sex affects calorie needs
• Height: Impacts your BMR calculation
• Weight: Current weight is essential for accurate calculations

Step 3: Select Your Activity Level

Choose from five options that best describe your weekly physical activity:

1. Sedentary: Little to no exercise (office job, minimal movement)
2. Lightly active: Light exercise 1-3 days/week
3. Moderately active: Moderate exercise 3-5 days/week
4. Very active: Hard exercise 6-7 days/week
5. Super active: Very hard exercise/physical job or training twice daily

Step 4: Choose Your Goal

Select your primary objective:

• Maintain weight: Keep your current body composition
• Lose weight: Create a calorie deficit for fat loss
• Gain weight: Create a calorie surplus for muscle growth

Understanding Your Results

After submitting your information, you'll receive a comprehensive analysis:

1. Daily Calorie Needs

Your personalized calorie target appears as:

• Maintenance calories: What you need to stay at your current weight
• Weight loss calories: Approximately 500 calories below maintenance
• Weight gain calories: Approximately 500 calories above maintenance

2. Macronutrient Distribution

We provide a balanced macronutrient breakdown:

• Proteins (30%): Essential for muscle repair and growth
  Calculation: 0.3 × total calories ÷ 4 calories per gram
• Carbohydrates (40%): Primary energy source
  Calculation: 0.4 × total calories ÷ 4 calories per gram
• Fats (30%): Important for hormone production and nutrient absorption
  Calculation: 0.3 × total calories ÷ 9 calories per gram

The visual macro bar helps you quickly understand the proportion of each macronutrient.

3. BMI Calculation

Your Body Mass Index (BMI) is calculated as:

BMI = weight (kg) ÷ (height (m))²

With interpretation:

• Underweight: <18.5
• Normal weight: 18.5-24.9
• Overweight: 25-29.9
• Obese: ≥30

The Science Behind Our Calculations

BMR Calculation (Mifflin-St Jeor Equation)

We use the most accurate BMR formula available:

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

Activity Multipliers

We apply these factors to your BMR:

• Sedentary: ×1.2
• Lightly active: ×1.375
• Moderately active: ×1.55
• Very active: ×1.725
• Super active: ×1.9

Goal Adjustment

We adjust your TDEE based on your goal:

• Weight loss: -500 kcal/day (~1 lb/week loss)
• Weight gain: +500 kcal/day (~1 lb/week gain)
• Maintenance: No adjustment

Understanding Macronutrients

Proteins

• Build and repair tissues
• 4 calories per gram
• Sources: meat, fish, eggs, dairy, legumes

Carbohydrates

• Primary energy source
• 4 calories per gram
• Sources: grains, fruits, vegetables, legumes

Fats

• Essential for hormone production
• 9 calories per gram
• Sources: oils, nuts, seeds, avocado, fatty fish

Tips, FAQs & Practical Applications

Practical Applications

For Weight Loss

1. Use your calculated calorie target as a daily maximum
2. Combine with regular exercise for best results
3. Monitor progress weekly and adjust as needed

For Muscle Gain

1. Ensure you meet your calorie target daily
2. Focus on protein intake for muscle synthesis
3. Combine with resistance training

For Maintenance

1. Use your maintenance calories as a guide
2. Adjust slightly based on weekly weight trends
3. Maintain balanced macronutrients for optimal health

Frequently Asked Questions

Q: How often should I recalculate my calories?
A: Recalculate every:

• 10-15 lbs of weight change
• Significant change in activity level
• Every 3 months to account for metabolic adaptation

Q: Why are my macros set at 40/30/30?
A: This balanced ratio works well for most people, but you can adjust based on:

• Low-carb diets (reduce carbs, increase fats)
• High-protein diets (increase protein, reduce carbs/fats)

Q: Is BMI always accurate?
A: While useful for populations, BMI has limitations:

• Doesn't account for muscle mass
• May misclassify athletic individuals
• Use in combination with other measurements

Tips for Success

1. Track consistently: Use a food diary app for accuracy
2. Weigh yourself:
   • Same time each day
   • Same conditions (morning, after bathroom)
   • Weekly averages are more meaningful than daily numbers
3. Be patient: Healthy weight changes take time
4. Prioritize nutrition: Focus on whole, nutrient-dense foods
5. Stay hydrated: Water affects weight and metabolism