Estimate your daily caloric needs and macronutrient breakdown (protein, carbohydrates, and fats) based on your personal details and fitness goals.
kg
cm
Sedentary (little or no exercise)
Lightly Active (light exercise/sports 1-3 days/week)
Moderately Active (moderate exercise/sports 3-5 days/week)
Very Active (hard exercise/sports 6-7 days/week)
Extra Active (very hard exercise/physical job)
Maintain Weight
Mild Weight Loss (0.25 kg/week)
Moderate Weight Loss (0.5 kg/week)
Extreme Weight Loss (1 kg/week)
Mild Weight Gain (0.25 kg/week)
Moderate Weight Gain (0.5 kg/week)
Extreme Weight Gain (1 kg/week)
/* Basic styling for the calculator */
.calculator-container {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
background-color: #f9f9f9;
border: 1px solid #ddd;
border-radius: 8px;
padding: 20px;
max-width: 600px;
margin: 20px auto;
box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}
.calculator-container h2 {
color: #333;
text-align: center;
margin-bottom: 20px;
}
.calculator-container p {
color: #555;
text-align: center;
margin-bottom: 25px;
line-height: 1.6;
}
.calc-input-group {
margin-bottom: 15px;
display: flex;
flex-wrap: wrap;
align-items: center;
}
.calc-input-group label {
flex: 1 1 150px;
color: #333;
font-weight: bold;
margin-right: 10px;
}
.calc-input-group input[type="number"],
.calc-input-group select {
flex: 2 1 200px;
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.calc-input-group input[type="radio"] {
margin-left: 10px;
margin-right: 5px;
}
.calc-input-group span {
margin-left: 5px;
font-weight: bold;
color: #666;
}
.calculate-button {
display: block;
width: 100%;
padding: 12px 20px;
background-color: #007bff;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
cursor: pointer;
margin-top: 20px;
transition: background-color 0.3s ease;
}
.calculate-button:hover {
background-color: #0056b3;
}
.calculator-results {
background-color: #e9f7ef;
border: 1px solid #d4edda;
border-radius: 8px;
padding: 15px;
margin-top: 25px;
color: #155724;
font-size: 17px;
line-height: 1.8;
}
.calculator-results h3 {
color: #0f5132;
margin-top: 0;
text-align: center;
margin-bottom: 15px;
}
.calculator-results p {
margin: 5px 0;
text-align: left;
color: #155724;
}
.calculator-results strong {
color: #0f5132;
}
@media (max-width: 480px) {
.calc-input-group label {
flex: 1 1 100%;
margin-bottom: 5px;
}
.calc-input-group input[type="number"],
.calc-input-group select {
flex: 1 1 100%;
}
}
function toggleUnits() {
var unitsMetric = document.getElementById('unitsMetric').checked;
var weightInput = document.getElementById('weight');
var heightInput = document.getElementById('height');
var weightUnitSpan = document.getElementById('weightUnit');
var heightUnitSpan = document.getElementById('heightUnit');
if (unitsMetric) {
// Convert from Imperial to Metric
if (weightInput.value && weightUnitSpan.dataset.currentUnit === 'lbs') {
weightInput.value = (parseFloat(weightInput.value) / 2.20462).toFixed(1);
}
if (heightInput.value && heightUnitSpan.dataset.currentUnit === 'inches') {
heightInput.value = (parseFloat(heightInput.value) * 2.54).toFixed(0);
}
weightUnitSpan.textContent = 'kg';
heightUnitSpan.textContent = 'cm';
weightInput.min = "30";
weightInput.max = "300";
heightInput.min = "100";
heightInput.max = "250";
} else {
// Convert from Metric to Imperial
if (weightInput.value && weightUnitSpan.dataset.currentUnit === 'kg') {
weightInput.value = (parseFloat(weightInput.value) * 2.20462).toFixed(1);
}
if (heightInput.value && heightUnitSpan.dataset.currentUnit === 'cm') {
heightInput.value = (parseFloat(heightInput.value) / 2.54).toFixed(0);
}
weightUnitSpan.textContent = 'lbs';
heightUnitSpan.textContent = 'inches';
weightInput.min = "60";
weightInput.max = "660";
heightInput.min = "40";
heightInput.max = "100";
}
weightUnitSpan.dataset.currentUnit = unitsMetric ? 'kg' : 'lbs';
heightUnitSpan.dataset.currentUnit = unitsMetric ? 'cm' : 'inches';
}
// Initialize unit display on load
document.addEventListener('DOMContentLoaded', function() {
document.getElementById('weightUnit').dataset.currentUnit = 'kg';
document.getElementById('heightUnit').dataset.currentUnit = 'cm';
toggleUnits(); // Ensure initial state is correct based on default radio button
});
function calculateMacros() {
var age = parseFloat(document.getElementById('age').value);
var genderMale = document.getElementById('genderMale').checked;
var weight = parseFloat(document.getElementById('weight').value);
var height = parseFloat(document.getElementById('height').value);
var activityFactor = parseFloat(document.getElementById('activityLevel').value);
var goal = document.getElementById('goal').value;
var unitsMetric = document.getElementById('unitsMetric').checked;
// Input validation
if (isNaN(age) || age 100) {
document.getElementById('macroResults').innerHTML = 'Please enter a valid age (15-100 years).';
return;
}
if (isNaN(weight) || weight <= 0) {
document.getElementById('macroResults').innerHTML = 'Please enter a valid weight.';
return;
}
if (isNaN(height) || height <= 0) {
document.getElementById('macroResults').innerHTML = 'Please enter a valid height.';
return;
}
var weight_kg = weight;
var height_cm = height;
// Convert to metric if imperial units are selected
if (!unitsMetric) {
weight_kg = weight / 2.20462; // lbs to kg
height_cm = height * 2.54; // inches to cm
}
// Step 1: Calculate Basal Metabolic Rate (BMR) – Mifflin-St Jeor Equation
var bmr;
if (genderMale) {
bmr = (10 * weight_kg) + (6.25 * height_cm) – (5 * age) + 5;
} else {
bmr = (10 * weight_kg) + (6.25 * height_cm) – (5 * age) – 161;
}
// Step 2: Calculate Total Daily Energy Expenditure (TDEE)
var tdee = bmr * activityFactor;
// Step 3: Adjust TDEE for Goal
var targetCalories = tdee;
var calorieAdjustment = 0;
switch (goal) {
case 'mildLoss':
calorieAdjustment = -250; // Approx 0.25 kg/week
break;
case 'moderateLoss':
calorieAdjustment = -500; // Approx 0.5 kg/week
break;
case 'extremeLoss':
calorieAdjustment = -1000; // Approx 1 kg/week
break;
case 'mildGain':
calorieAdjustment = 250;
break;
case 'moderateGain':
calorieAdjustment = 500;
break;
case 'extremeGain':
calorieAdjustment = 1000;
break;
case 'maintain':
default:
calorieAdjustment = 0;
break;
}
targetCalories = tdee + calorieAdjustment;
// Ensure minimum calorie intake for health
var minCalories = genderMale ? 1500 : 1200;
var warningMessage = '';
if (targetCalories < minCalories) {
warningMessage = 'Warning: Your calculated calorie target is below the recommended minimum for healthy adults. Consult a professional.';
targetCalories = minCalories; // Cap at minimum for display, but warn
}
// Step 4: Calculate Macronutrient Split (using a common percentage split)
// Default split: Protein 30%, Fat 25%, Carbs 45%
var proteinGrams = (targetCalories * 0.30) / 4; // 4 calories per gram of protein
var fatGrams = (targetCalories * 0.25) / 9; // 9 calories per gram of fat
var carbGrams = (targetCalories * 0.45) / 4; // 4 calories per gram of carbohydrate
// Display results
var resultsHtml = '
Understanding Your Macronutrients: The Key to Your Fitness Goals
Whether you're aiming for weight loss, muscle gain, or simply better health, understanding and tracking your macronutrients (macros) can be a game-changer. Our online macro calculator is designed to provide you with a personalized estimate of your daily caloric needs and the ideal breakdown of protein, carbohydrates, and fats to help you achieve your objectives.
What are Macronutrients?
Macronutrients are the nutrients your body needs in large amounts to provide energy and support various bodily functions. There are three primary macronutrients:
Protein: Essential for building and repairing tissues, producing enzymes and hormones, and supporting immune function. Found in meat, fish, eggs, dairy, legumes, and nuts. Each gram of protein provides approximately 4 calories.
Carbohydrates: The body's primary source of energy. They fuel your brain, muscles, and central nervous system. Found in grains, fruits, vegetables, and legumes. Each gram of carbohydrate provides approximately 4 calories.
Fats: Crucial for hormone production, nutrient absorption, cell growth, and providing a concentrated source of energy. Found in oils, nuts, seeds, avocados, and fatty meats. Each gram of fat provides approximately 9 calories.
Why Track Macros?
While calorie counting focuses solely on the total energy intake, macro tracking delves deeper into the composition of those calories. This approach offers several benefits:
Targeted Goals: Different macro ratios can optimize results for specific goals. For example, higher protein intake is often recommended for muscle gain and satiety during weight loss.
Improved Body Composition: By ensuring adequate protein, you can preserve muscle mass during a calorie deficit or build it during a surplus, leading to a more favorable body composition.
Better Energy Levels: Balancing carbs and fats can help stabilize blood sugar, providing consistent energy throughout the day and preventing crashes.
Nutrient Density: Focusing on macros often encourages a more mindful approach to food choices, leading to a diet rich in whole, unprocessed foods.
How Our Macro Calculator Works
Our calculator uses scientifically recognized formulas to estimate your daily needs:
Basal Metabolic Rate (BMR): This is the number of calories your body burns at rest to maintain basic bodily functions (breathing, circulation, cell production). We use the Mifflin-St Jeor equation, which is widely considered one of the most accurate BMR formulas.
Total Daily Energy Expenditure (TDEE): Your BMR is then multiplied by an activity factor to account for your daily physical activity, giving you an estimate of the total calories you burn in a day.
Goal Adjustment: Based on your chosen goal (weight loss, maintenance, or gain), we adjust your TDEE to create a calorie deficit or surplus.
Macronutrient Split: Finally, your target daily calories are divided into recommended percentages for protein, carbohydrates, and fats. Our calculator uses a common split of 30% Protein, 45% Carbohydrates, and 25% Fats, which is suitable for general fitness goals.
Using the Calculator Effectively
To get the most accurate results, provide honest information about your age, gender, current weight, height, and activity level. Select your primary goal, and the calculator will do the rest.
Remember, these are estimates. Individual needs can vary based on genetics, metabolism, specific training intensity, and health conditions. It's always recommended to consult with a healthcare professional or a registered dietitian for personalized advice, especially if you have underlying health concerns or are aiming for extreme changes.
Tips for Macro Tracking
Start Simple: Don't aim for perfection immediately. Focus on hitting your protein target first, then adjust carbs and fats.
Use a Food Tracker App: Apps like MyFitnessPal or Cronometer can help you log your food and track your macro intake.
Prioritize Whole Foods: Base your diet around lean proteins, complex carbohydrates, and healthy fats from whole, unprocessed sources.
Adjust as Needed: Monitor your progress over a few weeks. If you're not seeing the desired results, you may need to slightly adjust your calorie intake or macro ratios.
Stay Hydrated: Water is crucial for all bodily functions, including metabolism and nutrient transport.
Empower yourself with the knowledge to fuel your body optimally. Use our macro calculator as a starting point on your journey to better health and fitness!