Calculate your optimal daily caloric intake to effectively build muscle mass. Understanding your energy needs is crucial for bulking.
Muscle Gain Calorie Calculator
Enter your weight in kilograms (kg).
Enter your height in centimeters (cm).
Enter your age in years.
Male
Female
Select your gender.
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 a week)
Extra Active (very hard exercise/sports & physical job or 2x training)
Choose the option that best describes your lifestyle.
Enter your desired weekly weight gain in kilograms (e.g., 0.25 to 0.5 kg).
Copied!
Your Muscle Gain Nutrition Plan
Your Daily Caloric Target for Muscle Gain:
— kcal
BMR (Basal Metabolic Rate): — kcal
TDEE (Total Daily Energy Expenditure): — kcal
Caloric Surplus for Gain: — kcal
Calculated using the Mifflin-St Jeor Equation for BMR, then adjusted for activity level (TDEE), and finally adding a caloric surplus for muscle gain.
Caloric Intake Breakdown
Daily caloric needs for maintenance and muscle gain.
Nutrient Macronutrient Recommendations
Macronutrient
Percentage of Calories
Grams per Day
Protein
—
—
Carbohydrates
—
—
Fats
—
—
Recommended daily macronutrient targets for muscle gain.
What is a Calorie Calculator for Muscle Gain?
A calorie calculator for muscle gain, often referred to as a "bulking calculator," is a specialized tool designed to estimate the total daily caloric intake required to support muscle hypertrophy (growth). It goes beyond simply calculating your maintenance calories (Total Daily Energy Expenditure or TDEE) by incorporating an additional caloric surplus – the extra energy needed to fuel the muscle-building process. This tool is invaluable for athletes, bodybuilders, and anyone looking to increase their muscle mass effectively and efficiently.
Who should use it? Anyone aiming to gain muscle, from beginners starting their fitness journey to experienced athletes looking to optimize their bulking phase. It's also useful for individuals who find it difficult to gain weight and want a structured approach to increasing caloric intake.
Common misconceptions surrounding muscle gain include the belief that any excess calories lead to muscle growth (in reality, a targeted surplus is needed to minimize fat gain), or that protein alone is sufficient without adequate overall calories. This calculator helps demystify the precise caloric requirements.
Calorie Calculator for Muscle Gain Formula and Mathematical Explanation
The process of calculating your caloric needs for muscle gain involves several steps, starting with your Basal Metabolic Rate (BMR), then factoring in your activity level to estimate Total Daily Energy Expenditure (TDEE), and finally adding a surplus to promote anabolism (muscle building).
Step 1: Calculate Basal Metabolic Rate (BMR)
We use the Mifflin-St Jeor equation, which is widely considered one of the most accurate formulas:
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
Step 2: Calculate Total Daily Energy Expenditure (TDEE)
TDEE is your BMR multiplied by an activity factor:
TDEE = BMR × Activity Factor
The activity factors are standardized values representing different levels of physical activity.
Step 3: Calculate Caloric Surplus for Muscle Gain
To gain muscle, you need to consume more calories than you burn. A moderate surplus is recommended to prioritize muscle gain while minimizing excessive fat accumulation.
Target Daily Calories = TDEE + Caloric Surplus
A common recommendation for a healthy surplus is approximately 250-500 kcal per day, which aims for a weight gain of about 0.25-0.5 kg per week.
Step 4: Macronutrient Breakdown (Recommendations)
Once your target calorie intake is determined, macronutrients are distributed:
Protein: Crucial for muscle repair and synthesis. Recommended intake is typically 1.6 to 2.2 grams per kilogram of body weight.
Fats: Essential for hormone production and overall health. Recommended intake is around 20-30% of total calories.
Carbohydrates: Provide energy for workouts and daily activities. The remaining calories after protein and fat intake are allocated to carbohydrates.
Variables Table:
Variable
Meaning
Unit
Typical Range
Weight
Current body mass
kg
30 – 200+
Height
Body height
cm
100 – 220
Age
Years since birth
Years
10 – 100+
Gender
Biological sex
N/A
Male / Female
Activity Factor
Multiplier for physical activity level
Decimal
1.2 – 1.9
Target Weight Gain
Desired weekly increase in body mass
kg/week
0.1 – 1.0
BMR
Calories burned at rest
kcal/day
1200 – 2500+
TDEE
Total calories burned daily including activity
kcal/day
1800 – 4000+
Caloric Surplus
Extra calories for muscle gain
kcal/day
250 – 750
Target Daily Calories
Total intake for muscle gain
kcal/day
2050 – 4750+
Practical Examples (Real-World Use Cases)
Example 1: The Aspiring Bodybuilder
Scenario: John is a 28-year-old male, 175 cm tall, weighing 70 kg. He trains intensely 5 days a week (moderately active) and wants to gain muscle mass. He aims for a sustainable gain of 0.5 kg per week.
Inputs:
Weight: 70 kg
Height: 175 cm
Age: 28 years
Gender: Male
Activity Level: Moderately Active (1.55)
Target Weight Gain: 0.5 kg/week
Calculated Results (Illustrative):
BMR: Approximately 1700 kcal
TDEE: Approximately 2635 kcal (1700 * 1.55)
Caloric Surplus: Approximately 500 kcal (for 0.5 kg/week gain)
Target Daily Calories for Muscle Gain: 3135 kcal
Recommended Protein: ~140g (2g/kg)
Recommended Fat: ~87g (25% of calories)
Recommended Carbs: ~446g (remaining calories)
Interpretation: John needs to consume around 3135 calories daily, focusing on adequate protein intake and sufficient carbohydrates to fuel his intense training and muscle recovery. This provides a clear dietary target for his bulking phase.
Example 2: The Woman Seeking Lean Muscle
Scenario: Sarah is a 23-year-old female, 165 cm tall, weighing 58 kg. She engages in strength training 3-4 times a week (lightly active) and wishes to build lean muscle with minimal fat gain. She targets a gain of 0.25 kg per week.
Inputs:
Weight: 58 kg
Height: 165 cm
Age: 23 years
Gender: Female
Activity Level: Lightly Active (1.375)
Target Weight Gain: 0.25 kg/week
Calculated Results (Illustrative):
BMR: Approximately 1325 kcal
TDEE: Approximately 1822 kcal (1325 * 1.375)
Caloric Surplus: Approximately 250 kcal (for 0.25 kg/week gain)
Target Daily Calories for Muscle Gain: 2072 kcal
Recommended Protein: ~116g (2g/kg)
Recommended Fat: ~58g (25% of calories)
Recommended Carbs: ~249g (remaining calories)
Interpretation: Sarah should aim for approximately 2072 calories per day. Her focus should be on hitting her protein goal while ensuring she has enough carbohydrates for energy and essential fats for hormonal health, supporting her goal of lean muscle development.
How to Use This Calorie Calculator for Muscle Gain
Utilizing this calorie calculator is straightforward and provides actionable insights for your muscle-building journey. Follow these steps:
Enter Your Current Stats: Accurately input your current weight (in kg), height (in cm), age (in years), and select your gender. Precision here is key for accurate BMR calculation.
Select Your Activity Level: Choose the option that best reflects your weekly physical activity. Be honest; overestimating can lead to unnecessarily high calorie targets, potentially causing excessive fat gain.
Set Your Goal: Specify your desired weekly weight gain. A common recommendation for muscle gain is between 0.25 kg to 0.5 kg per week. Smaller, consistent gains are often more sustainable and prioritize muscle over fat.
Calculate: Click the "Calculate My Calories" button.
How to Read Results:
Target Daily Calories for Muscle Gain: This is your primary goal – the total number of calories you should aim to consume each day to support muscle growth.
BMR (Basal Metabolic Rate): The calories your body burns at complete rest.
TDEE (Total Daily Energy Expenditure): Your BMR plus the calories burned through all daily activities and exercise. This is your maintenance calorie level.
Caloric Surplus: The extra calories you're adding to your TDEE to fuel muscle growth.
Macronutrient Recommendations: These provide a breakdown of how to distribute your total calories among protein, carbohydrates, and fats, which is vital for optimizing muscle protein synthesis and energy levels.
Decision-Making Guidance: Use the calculated target calories as a baseline. Monitor your progress (weight, body measurements, strength levels) weekly. If you are not gaining weight or muscle, slightly increase your calorie intake (e.g., by 100-200 kcal). If you are gaining weight too rapidly with noticeable fat accumulation, slightly decrease your intake or ensure your training intensity is sufficient. Adjust based on your body's response and your specific fitness goals.
Key Factors That Affect Calorie Calculator for Muscle Gain Results
While the calculator provides a scientifically-backed estimate, several real-world factors can influence your actual caloric needs for muscle gain:
Genetics: Individual genetic makeup plays a significant role in metabolism, muscle-building potential, and how efficiently your body utilizes nutrients. Some individuals naturally have a faster metabolism or respond better to training stimuli.
Hormonal Profile: Hormones like testosterone, growth hormone, and insulin are critical for muscle growth. Imbalances or individual variations in these hormones can affect how effectively you gain muscle even with optimal caloric intake.
Training Intensity and Volume: The effectiveness and consistency of your resistance training program are paramount. Higher intensity, well-structured training sessions require more energy and stimulate greater muscle protein synthesis, potentially increasing caloric needs. Poor training might lead to less muscle gain despite a surplus.
Nutrient Timing and Quality: While total daily calories and macronutrients are most important, the *quality* of the food consumed matters. Nutrient-dense foods provide essential micronutrients that support overall health and recovery. Nutrient timing (e.g., post-workout nutrition) can also play a role, though its impact is often debated compared to total intake.
Sleep Quality and Recovery: Muscle growth and repair primarily occur during rest. Insufficient or poor-quality sleep can impair recovery, increase stress hormones (like cortisol), and hinder muscle protein synthesis, making it harder to gain muscle even with a caloric surplus.
Metabolic Adaptations: Over time, especially with consistent dieting or training, your metabolism can adapt. For instance, prolonged calorie deficits can lower your metabolic rate, while long-term bulking might slightly increase it. This calculator provides a starting point, but ongoing adjustments are often necessary.
Cardiovascular Exercise: While crucial for health, excessive or overly intense cardio can create a significant calorie deficit, potentially counteracting your muscle gain efforts if not accounted for in your intake.
Age and Experience: Younger individuals often have a hormonal advantage for muscle growth. Beginners typically experience "newbie gains" more readily than highly trained individuals who require more precise programming and nutrition to see further progress.
Frequently Asked Questions (FAQ)
How much weight should I aim to gain per week?
For optimal muscle gain while minimizing fat accumulation, aim for 0.25 kg to 0.5 kg (approximately 0.5 to 1 lb) per week. Gaining faster often leads to a higher proportion of fat gain.
What if I'm gaining fat too quickly?
If you notice excessive fat gain, reduce your daily caloric intake slightly (e.g., by 100-200 kcal) or ensure your training intensity is high enough to utilize the surplus for muscle rather than fat storage. Re-evaluate your activity level as well.
Can I use this calculator if I'm vegetarian or vegan?
Yes, the calorie calculation remains the same. However, achieving the recommended protein intake may require more careful planning with plant-based sources. Focus on protein-rich vegetarian/vegan foods like lentils, beans, tofu, tempeh, and plant-based protein powders.
Does this calculator account for supplements?
No, this calculator estimates your caloric needs from whole foods. If you use supplements like protein powder or mass gainers, their caloric content should be factored into your total daily intake.
Is it possible to gain muscle and lose fat simultaneously?
It's challenging but possible, particularly for beginners, individuals returning after a break, or those with a higher body fat percentage. This typically requires a smaller caloric deficit or maintenance calories, combined with high protein intake and consistent, intense training. For most, dedicated bulking (calorie surplus) and cutting (calorie deficit) phases are more efficient.
How long should I stay in a caloric surplus?
The duration varies based on individual goals and progress. Typically, bulking phases can last anywhere from 8 to 20 weeks, followed by a cutting phase or a period of maintenance to allow the body to recover and adapt.
What are the best food sources for muscle gain?
Focus on whole, unprocessed foods. Excellent sources include lean meats (chicken, turkey, beef), fish, eggs, dairy (milk, yogurt, cheese), legumes (beans, lentils), whole grains (oats, brown rice, quinoa), fruits, and vegetables. Combining these ensures adequate protein, complex carbohydrates, healthy fats, and micronutrients.
Should I adjust my intake on rest days?
Some people prefer to slightly reduce their caloric intake on rest days (e.g., by 100-200 kcal) as energy expenditure is lower. However, maintaining a consistent intake aligned with your TDEE + Surplus is often simpler and effective for muscle gain.
Related Tools and Internal Resources
BMI Calculator: Understand your Body Mass Index for overall health assessment.
Macronutrient Calculator: Get a detailed breakdown of protein, carb, and fat targets for various fitness goals.
BMR Calculator: Calculate your Basal Metabolic Rate to understand your resting energy needs.
TDEE Calculator: Estimate your Total Daily Energy Expenditure based on activity level.
Water Intake Calculator: Determine optimal daily hydration levels for health and performance.
Leverage these resources alongside the muscle gain calorie calculator for a comprehensive approach to your health and fitness journey. Understanding each metric helps in making informed decisions about your diet and training.
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var heightInput = document.getElementById('height');
var ageInput = document.getElementById('age');
var genderSelect = document.getElementById('gender');
var activityLevelSelect = document.getElementById('activityLevel');
var goalWeightInput = document.getElementById('goalWeight');
var weightError = document.getElementById('weightError');
var heightError = document.getElementById('heightError');
var ageError = document.getElementById('ageError');
var goalWeightError = document.getElementById('goalWeightError');
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var primaryResult = document.getElementById('primaryResult');
var bmrResult = document.getElementById('bmrResult');
var tdeeResult = document.getElementById('tdeeResult');
var surplusResult = document.getElementById('surplusResult');
var proteinPercent = document.getElementById('proteinPercent');
var proteinGrams = document.getElementById('proteinGrams');
var carbPercent = document.getElementById('carbPercent');
var carbGrams = document.getElementById('carbGrams');
var fatPercent = document.getElementById('fatPercent');
var fatGrams = document.getElementById('fatGrams');
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var canvas = document.getElementById('calorieChart');
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function calculateBMR(weight, height, age, gender) {
var bmr = 0;
if (gender === 'male') {
bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5;
} else {
bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161;
}
return Math.round(bmr);
}
function calculateTDEE(bmr, activityFactor) {
return Math.round(bmr * activityFactor);
}
function calculateSurplus(targetGainKgPerWeek) {
// Approximately 7700 kcal per kg of body weight
return Math.round(targetGainKgPerWeek * 7700 / 7);
}
function calculateMacros(totalCalories, weightKg) {
var proteinGrams = Math.max(1.6 * weightKg, 2.2 * weightKg); // Aim for 1.6-2.2g/kg
var proteinCalories = proteinGrams * 4;
var fatPercentage = 0.25; // Aim for 25% of calories from fat
var fatCalories = totalCalories * fatPercentage;
var fatGrams = fatCalories / 9;
var carbCalories = totalCalories – proteinCalories – fatCalories;
var carbGrams = carbCalories / 4;
// Ensure we don't have negative carbs if protein/fat are very high
if (carbCalories < 0) {
// Adjust fat slightly if needed, but prioritize protein
var shortfall = Math.abs(carbCalories);
fatCalories -= shortfall;
fatGrams = fatCalories / 9;
carbCalories = 0;
carbGrams = 0;
if (fatCalories < 0) { // If even fat is negative, something is wrong with inputs
console.error("Calorie calculation resulted in negative fat calories.");
return { proteinGrams: 0, carbGrams: 0, fatGrams: 0 };
}
}
return {
proteinGrams: Math.round(proteinGrams),
carbGrams: Math.round(carbGrams),
fatGrams: Math.round(fatGrams)
};
}
function updateChart(tdee, targetCalories) {
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chartInstance.destroy();
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var ctx = canvas.getContext('2d');
chartInstance = new Chart(ctx, {
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data: {
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function calculateCalories() {
var isValid = true;
if (!validateInput(weightInput, weightError, 1)) isValid = false;
if (!validateInput(heightInput, heightError, 1)) isValid = false;
if (!validateInput(ageInput, ageError, 1)) isValid = false;
if (!validateInput(goalWeightInput, goalWeightError, 0.01, 2)) isValid = false; // Allow small gains, cap high
if (!isValid) {
primaryResultContainer.style.display = 'none';
bmrResult.style.display = 'none';
tdeeResult.style.display = 'none';
surplusResult.style.display = 'none';
macroTableBody.style.display = 'none'; // Hide macro table on error
if (chartInstance) chartInstance.destroy();
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var weight = parseFloat(weightInput.value);
var height = parseFloat(heightInput.value);
var age = parseInt(ageInput.value);
var gender = genderSelect.value;
var activityFactor = parseFloat(activityLevelSelect.value);
var targetGainKgPerWeek = parseFloat(goalWeightInput.value);
var bmr = calculateBMR(weight, height, age, gender);
var tdee = calculateTDEE(bmr, activityFactor);
var surplus = calculateSurplus(targetGainKgPerWeek);
var targetCalories = tdee + surplus;
var macros = calculateMacros(targetCalories, weight);
primaryResult.textContent = targetCalories.toLocaleString();
primaryResultContainer.style.display = 'block';
bmrResult.style.display = 'block';
bmrResult.children[0].textContent = 'BMR (Basal Metabolic Rate): ';
bmrResult.children[1].textContent = bmr.toLocaleString() + ' kcal';
tdeeResult.style.display = 'block';
tdeeResult.children[0].textContent = 'TDEE (Total Daily Energy Expenditure): ';
tdeeResult.children[1].textContent = tdee.toLocaleString() + ' kcal';
surplusResult.style.display = 'block';
surplusResult.children[0].textContent = 'Caloric Surplus for Gain: ';
surplusResult.children[1].textContent = surplus.toLocaleString() + ' kcal';
// Update Macronutrient Table
macroTableBody.style.display = 'table-row-group'; // Make sure table is visible
proteinPercent.textContent = ((macros.proteinGrams * 4) / targetCalories * 100).toFixed(1) + '%';
proteinGrams.textContent = macros.proteinGrams.toLocaleString() + ' g';
carbPercent.textContent = ((macros.carbGrams * 4) / targetCalories * 100).toFixed(1) + '%';
carbGrams.textContent = macros.carbGrams.toLocaleString() + ' g';
fatPercent.textContent = ((macros.fatGrams * 9) / targetCalories * 100).toFixed(1) + '%';
fatGrams.textContent = macros.fatGrams.toLocaleString() + ' g';
// Update Chart
updateChart(tdee, targetCalories);
}
function resetCalculator() {
weightInput.value = "75";
heightInput.value = "180";
ageInput.value = "25";
genderSelect.value = "male";
activityLevelSelect.value = "1.55"; // Moderately Active
goalWeightInput.value = "0.5";
weightError.textContent = ""; weightError.style.display = 'none';
heightError.textContent = ""; heightError.style.display = 'none';
ageError.textContent = ""; ageError.style.display = 'none';
goalWeightError.textContent = ""; goalWeightError.style.display = 'none';
primaryResultContainer.style.display = 'none';
bmrResult.style.display = 'none';
tdeeResult.style.display = 'none';
surplusResult.style.display = 'none';
macroTableBody.style.display = 'none';
if (chartInstance) chartInstance.destroy();
copyStatus.classList.remove('show');
// Recalculate with default values
calculateCalories();
}
function copyResults() {
var weight = parseFloat(weightInput.value);
var height = parseFloat(heightInput.value);
var age = parseInt(ageInput.value);
var gender = genderSelect.options[genderSelect.selectedIndex].text;
var activityLevel = activityLevelSelect.options[activityLevelSelect.selectedIndex].text;
var targetGainKgPerWeek = parseFloat(goalWeightInput.value);
var bmrVal = parseFloat(bmrResult.children[1].textContent.replace(/,/g, '').replace(' kcal', ''));
var tdeeVal = parseFloat(tdeeResult.children[1].textContent.replace(/,/g, '').replace(' kcal', ''));
var surplusVal = parseFloat(surplusResult.children[1].textContent.replace(/,/g, '').replace(' kcal', ''));
var targetCaloriesVal = parseFloat(primaryResult.textContent.replace(/,/g, ''));
var proteinG = parseFloat(proteinGrams.textContent.replace(/,/g, '').replace(' g', ''));
var carbG = parseFloat(carbGrams.textContent.replace(/,/g, '').replace(' g', ''));
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"Target Gain: " + targetGainKgPerWeek.toLocaleString() + " kg/week"
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resultsText += "Caloric Surplus for Gain: " + surplusVal.toLocaleString() + " kcal\n";
resultsText += "Maintenance Calories (TDEE): " + tdeeVal.toLocaleString() + " kcal\n";
resultsText += "Basal Metabolic Rate (BMR): " + bmrVal.toLocaleString() + " kcal\n\n";
resultsText += "— Macronutrient Recommendations —\n";
resultsText += "Protein: " + proteinG.toLocaleString() + " g (" + proteinPercent.textContent + ")\n";
resultsText += "Carbohydrates: " + carbG.toLocaleString() + " g (" + carbPercent.textContent + ")\n";
resultsText += "Fats: " + fatG.toLocaleString() + " g (" + fatPercent.textContent + ")\n\n";
resultsText += "— Key Assumptions —\n";
resultsText += assumptions.join('\n');
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tempTextArea.select();
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setTimeout(function() {
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// Initialize chart with dummy data or hide it until calculated
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labels: ['Maintenance (TDEE)', 'Muscle Gain Target'],
datasets: [{
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}
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// Initial calculation on load with default values
document.addEventListener('DOMContentLoaded', function() {
calculateCalories();
// Add event listeners for real-time updates (optional, but good UX)
weightInput.addEventListener('input', calculateCalories);
heightInput.addEventListener('input', calculateCalories);
ageInput.addEventListener('input', calculateCalories);
genderSelect.addEventListener('change', calculateCalories);
activityLevelSelect.addEventListener('change', calculateCalories);
goalWeightInput.addEventListener('input', calculateCalories);
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