Nutrition Calculator

Precision Nutrition & Macro Calculator

Calculate your Total Daily Energy Expenditure (TDEE) and optimal macronutrient split based on your physical profile and activity levels.

Male Female

Sedentary (Little or no exercise) Lightly Active (Exercise 1-3 days/week) Moderately Active (Exercise 3-5 days/week) Very Active (Hard exercise 6-7 days/week) Extra Active (Physical job & intense training)

Your Daily Targets

0

Daily Calories (TDEE)

0g

Protein

0g

Carbs

0g

Fats

Understanding Your Nutritional Needs

Managing your health begins with understanding energy balance. This Nutrition Calculator uses the Mifflin-St Jeor Equation, widely considered the most accurate formula for calculating Basal Metabolic Rate (BMR) in healthy adults.

How the Calculation Works

Your Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a 24-hour period. It is composed of four main components:

• BMR: The energy used for basic functions (breathing, circulation) at rest.
• Thermic Effect of Food: Calories burned during digestion.
• Non-Exercise Activity Thermogenesis (NEAT): Movement outside of formal exercise.
• Exercise: Formal training sessions.

Macronutrient Breakdown

Once your caloric needs are established, we distribute those calories into the three primary macros:

1. Protein (4 kcal/g): Essential for muscle repair and metabolic function. We calculate this at 30% of your total intake.
2. Carbohydrates (4 kcal/g): The primary fuel source for high-intensity activity. We set this at 40% of your total intake.
3. Fats (9 kcal/g): Vital for hormone production and brain health. We set this at 30% of your total intake.

Realistic Example

Consider a 35-year-old male, weighing 85kg at 182cm tall, with a moderately active lifestyle (3-5 days of exercise per week). His estimated TDEE would be approximately 2,850 calories. To maintain this weight, his daily macro split would be roughly 214g of Protein, 285g of Carbohydrates, and 95g of Fat.

Note: This calculator provides estimates. Individual metabolic rates can vary based on muscle mass, genetics, and health status. Consult with a registered dietitian for a personalized medical nutrition plan.

function calculateNutrition() { var age = parseFloat(document.getElementById('age').value); var gender = document.getElementById('gender').value; var weight = parseFloat(document.getElementById('weight').value); var height = parseFloat(document.getElementById('height').value); var activity = parseFloat(document.getElementById('activity').value); if (!age || !weight || !height || age <= 0 || weight <= 0 || height <= 0) { alert('Please enter valid positive numbers for age, weight, and height.'); return; } // Mifflin-St Jeor Equation var bmr; if (gender === 'male') { bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5; } else { bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161; } // TDEE Calculation var tdee = Math.round(bmr * activity); // Macro Splits (30% Protein, 40% Carbs, 30% Fats) var proteinGrams = Math.round((tdee * 0.30) / 4); var carbsGrams = Math.round((tdee * 0.40) / 4); var fatsGrams = Math.round((tdee * 0.30) / 9); // Display Results document.getElementById('total-calories').innerText = tdee.toLocaleString(); document.getElementById('macro-protein').innerText = proteinGrams + 'g'; document.getElementById('macro-carbs').innerText = carbsGrams + 'g'; document.getElementById('macro-fats').innerText = fatsGrams + 'g'; document.getElementById('results-area').style.display = 'block'; // Smooth scroll to results document.getElementById('results-area').scrollIntoView({ behavior: 'smooth', block: 'nearest' }); }