Calculate your TDEE and ideal macronutrient breakdown
Male
Female
Sedentary (Office job, little 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 + hard training)
Weight Loss (-500 kcal)
Maintenance
Weight Gain (+500 kcal)
Your Daily Requirements
Daily Calorie Goal
0
Calories per day
Protein
0g
30% of total
Carbs
0g
40% of total
Fats
0g
30% of total
Understanding Your Calorie and Macro Needs
Achieving your fitness goals, whether it is losing fat or building muscle, starts with understanding the energy balance. This Calorie and Macro Calculator uses the Mifflin-St Jeor equation, which is widely considered the most accurate formula for determining your Basal Metabolic Rate (BMR).
How Calories are Calculated
Your results are based on two main factors:
Basal Metabolic Rate (BMR): The energy your body burns just to keep you alive at rest.
Total Daily Energy Expenditure (TDEE): Your BMR multiplied by your physical activity level.
The Importance of Macronutrients
While calories determine if you lose or gain weight, macros (protein, carbohydrates, and fats) determine the quality of that weight change.
Protein (4 kcal/g): Essential for muscle repair and satiety. We recommend 30% for active individuals.
Carbohydrates (4 kcal/g): Your body's primary fuel source for high-intensity training.
Fats (9 kcal/g): Crucial for hormone production and brain health.
Practical Example
If you are a 30-year-old male weighing 80kg at 180cm height with a moderate activity level, your maintenance calories are roughly 2,750 per day. To lose weight safely (about 0.5kg per week), you would target 2,250 calories. Tracking your macros ensures that this weight loss comes primarily from fat stores rather than muscle tissue.
function calculateMacros() {
var gender = document.getElementById("gender").value;
var age = parseFloat(document.getElementById("age").value);
var weight = parseFloat(document.getElementById("weight").value);
var height = parseFloat(document.getElementById("height").value);
var activity = parseFloat(document.getElementById("activity").value);
var goal = parseFloat(document.getElementById("goal").value);
if (isNaN(age) || isNaN(weight) || isNaN(height)) {
alert("Please enter valid numbers for age, weight, and height.");
return;
}
var bmr;
if (gender === "male") {
bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5;
} else {
bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161;
}
var tdee = bmr * activity;
var targetCalories = Math.round(tdee + goal);
// Standard split: 30% Protein, 40% Carbs, 30% Fat
var proteinCals = targetCalories * 0.30;
var carbCals = targetCalories * 0.40;
var fatCals = targetCalories * 0.30;
var proteinGrams = Math.round(proteinCals / 4);
var carbGrams = Math.round(carbCals / 4);
var fatGrams = Math.round(fatCals / 9);
document.getElementById("total-calories").innerText = targetCalories.toLocaleString();
document.getElementById("protein-result").innerText = proteinGrams + "g";
document.getElementById("carbs-result").innerText = carbGrams + "g";
document.getElementById("fats-result").innerText = fatGrams + "g";
document.getElementById("results-area").style.display = "block";
// Smooth scroll to results
document.getElementById("results-area").scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}