Calorie Calculator to Gain Weight and Muscle

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Calorie Calculator to Gain Weight and Muscle

Calculate your daily caloric intake target to effectively gain muscle mass and healthy weight.

Muscle Gain Calorie Calculator

Enter your current body weight.
Enter your height in feet and inches.
Enter your age in years.
Male Female Select your gender.
Sedentary (little to 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/sports & physical job) Choose the option that best describes your lifestyle.
Recommended: 0.25-1 kg (0.5-2 lbs) per week.
Enter your estimated body fat percentage (e.g., 15 for 15%). If unknown, leave blank.

Your Muscle Gain Nutrition Plan

Basal Metabolic Rate (BMR): kcal
Total Daily Energy Expenditure (TDEE): kcal
Calorie Surplus for Muscle Gain: kcal
– kcal
How it works:

First, we calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, which estimates calories burned at rest. Then, we multiply BMR by your Activity Level to get your Total Daily Energy Expenditure (TDEE), the total calories you burn daily. To gain weight and muscle, you need to consume more calories than you burn. We add a calculated calorie surplus (based on your target weight gain per week) to your TDEE to determine your daily calorie target for muscle gain. A common surplus is 300-500 kcal per day for a gain of about 0.5-1 lb per week.

Weekly Calorie vs. Expenditure Projection

Visualizing your estimated daily expenditure and target intake for muscle gain over a week.

Nutritional Breakdown (Example Target)

This table provides an example macronutrient split based on your target calorie intake for muscle gain. Adjust based on your specific dietary preferences and needs.

Macronutrient Percentage of Calories Grams per Day (Example) Typical Food Sources
Protein 30-40% Chicken breast, fish, lean beef, eggs, Greek yogurt, tofu, legumes
Carbohydrates 40-50% Oats, rice, potatoes, whole grains, fruits, vegetables
Fats 20-30% Avocado, nuts, seeds, olive oil, fatty fish

What is a Calorie Calculator for Weight and Muscle Gain?

A calorie calculator to gain weight and muscle is an online tool designed to help individuals determine the optimal daily caloric intake required to achieve their goals of increasing body mass, specifically muscle tissue. Unlike calculators focused solely on weight loss or maintenance, this specialized tool accounts for the increased energy demands of muscle synthesis and the need for a caloric surplus. It takes into account personal metrics such as current weight, height, age, gender, activity level, and optionally, body fat percentage, to provide a personalized daily calorie target. The primary objective is to create a sustainable caloric environment that supports muscle hypertrophy (growth) without excessive fat accumulation.

Who should use it: This calculator is ideal for athletes, bodybuilders, fitness enthusiasts, and anyone looking to build muscle mass. Whether you are an ectomorph (naturally lean with a fast metabolism) struggling to gain weight, or a mesomorph or endomorph aiming to optimize lean mass gains, this tool provides a data-driven starting point. It's also useful for individuals recovering from illness or injury who need to regain muscle mass. If your goal is to improve strength, athletic performance, and physique through increased muscle, this calorie calculator is a valuable resource.

Common misconceptions: A frequent misunderstanding is that any calories will do for muscle gain. In reality, the quality of calories significantly impacts results. Consuming excessive amounts of processed foods and sugars can lead to substantial fat gain alongside minimal muscle gain. Another misconception is that a huge calorie surplus is always better; this can overwhelm the body's ability to efficiently build muscle, leading to more fat storage. Finally, many believe muscle gain is purely about diet, neglecting the crucial role of progressive resistance training and adequate protein intake.

Calorie Calculator for Weight and Muscle Gain Formula and Mathematical Explanation

The process of calculating calorie needs for muscle gain involves several steps, primarily focused on estimating energy expenditure and then adding a strategic surplus. The most common method utilizes the concept of Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE).

Step 1: Calculate Basal Metabolic Rate (BMR)

We use the Mifflin-St Jeor equation, considered one of the most accurate for estimating resting metabolic rate:

  • 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 calculated by multiplying the BMR by an activity factor:

TDEE = BMR × Activity Factor

The Activity Factors are standardized values representing different levels of physical activity:

  • Sedentary: 1.2
  • Lightly Active: 1.375
  • Moderately Active: 1.55
  • Very Active: 1.725
  • Extra Active: 1.9

Step 3: Calculate Calorie Surplus for Muscle Gain

To gain weight, a caloric surplus is necessary. For muscle gain, this surplus should be moderate to prioritize lean mass over fat:

Calorie Surplus = Target Weight Gain per Week (kg) × 7700 kcal/kg

A commonly recommended surplus is around 300-500 kcal per day, which roughly corresponds to gaining 0.5-1 lb (0.25-0.5 kg) of weight per week. This calculation converts the desired weekly gain into a daily surplus needed.

Step 4: Determine Target Daily Calories for Muscle Gain

The final target is the sum of TDEE and the calculated Calorie Surplus:

Target Daily Calories = TDEE + Calorie Surplus

Optional Adjustment using Body Fat Percentage:

If body fat percentage is known, more advanced calculations can be used (like Katch-McArdle, which uses lean body mass). However, for simplicity and general use, the Mifflin-St Jeor method with a moderate surplus is highly effective. A higher body fat percentage might suggest a slightly smaller surplus to minimize fat gain, while a very low body fat percentage might benefit from a slightly larger surplus.

Variables Table

Variable Meaning Unit Typical Range / Options
Weight Current body weight kg (or lbs converted to kg) Positive number (e.g., 50-150 kg)
Height Body height cm (or ft/in converted to cm) Positive number (e.g., 150-200 cm)
Age Age in years Years Positive integer (e.g., 18-80)
Gender Biological sex N/A Male, Female
Activity Factor Daily physical activity level Multiplier 1.2 (Sedentary) to 1.9 (Extra Active)
Target Weight Gain Desired weekly rate of weight increase kg/week (or lbs/week converted) 0.25 – 0.5 kg/week (0.5 – 1 lb/week) recommended
Body Fat Percentage Percentage of body mass that is fat % Optional (e.g., 5-40%)
BMR Basal Metabolic Rate kcal/day Calculated value
TDEE Total Daily Energy Expenditure kcal/day Calculated value
Calorie Surplus Extra calories needed daily for gain kcal/day Calculated value (typically 300-500 kcal)

Practical Examples (Real-World Use Cases)

Example 1: The Dedicated Athlete

Scenario: Alex is a 28-year-old male, weighing 78 kg and standing 180 cm tall. He trains intensely 5 days a week with weightlifting and cardio sessions. His goal is to increase muscle mass and reach 85 kg over the next few months. He estimates his body fat at around 14%.

Inputs:

  • Weight: 78 kg
  • Height: 180 cm
  • Age: 28
  • Gender: Male
  • Activity Level: Moderately Active (1.55)
  • Target Weight Gain per Week: 0.5 kg (recommended for lean gain)
  • Body Fat Percentage: 14%

Calculations:

  • BMR (Mifflin-St Jeor for Men): (10 * 78) + (6.25 * 180) – (5 * 28) + 5 = 780 + 1125 – 140 + 5 = 1770 kcal
  • TDEE: 1770 kcal * 1.55 = 2743.5 kcal
  • Calorie Surplus for 0.5 kg/week gain: (0.5 kg * 7700 kcal/kg) / 7 days = 3850 kcal / 7 days = 550 kcal/day
  • Target Daily Calories: 2743.5 + 550 = 3293.5 kcal

Results:

  • BMR: ~1770 kcal
  • TDEE: ~2744 kcal
  • Calorie Surplus: ~550 kcal
  • Target Daily Calories for Muscle Gain: ~3294 kcal

Interpretation: Alex needs to consume approximately 3300 calories per day to support his goal of gaining muscle mass at a rate of 0.5 kg per week, considering his current stats and activity level. This provides a solid foundation for his muscle-building journey, and he should monitor his progress and adjust intake as needed.

Example 2: The Hardgainer

Scenario: Ben is a 22-year-old male, 175 cm tall and weighing only 65 kg. He describes himself as a "hardgainer" with a fast metabolism and trains 3-4 times a week with weights. He wants to gain weight and muscle but struggles to put on mass. He estimates his body fat is around 10%.

Inputs:

  • Weight: 65 kg
  • Height: 175 cm
  • Age: 22
  • Gender: Male
  • Activity Level: Lightly Active (1.375)
  • Target Weight Gain per Week: 0.5 kg
  • Body Fat Percentage: 10%

Calculations:

  • BMR (Mifflin-St Jeor for Men): (10 * 65) + (6.25 * 175) – (5 * 22) + 5 = 650 + 1093.75 – 110 + 5 = 1638.75 kcal
  • TDEE: 1638.75 kcal * 1.375 = 2253.3 kcal
  • Calorie Surplus for 0.5 kg/week gain: 550 kcal/day (as calculated above)
  • Target Daily Calories: 2253.3 + 550 = 2803.3 kcal

Results:

  • BMR: ~1639 kcal
  • TDEE: ~2253 kcal
  • Calorie Surplus: ~550 kcal
  • Target Daily Calories for Muscle Gain: ~2803 kcal

Interpretation: Ben needs to aim for approximately 2800 calories daily. Given his "hardgainer" status, he might need to be extra vigilant with his nutrition, ensuring consistent intake and potentially experimenting with slightly higher surpluses if progress is slower than desired. Focusing on nutrient-dense foods is key.

How to Use This Calorie Calculator for Weight and Muscle Gain

Using the calorie calculator is straightforward. Follow these steps to get your personalized daily calorie target:

  1. Enter Your Current Weight: Input your weight in kilograms or pounds. The calculator will convert it to kilograms for accuracy.
  2. Provide Your Height: Enter your height in feet and inches, or directly in centimeters.
  3. Input Your Age: Provide your age in years.
  4. Select Your Gender: Choose 'Male' or 'Female' as this affects BMR calculations.
  5. Choose Your Activity Level: Select the option that best matches your typical weekly physical activity. Be honest to get the most accurate TDEE.
  6. Set Your Target Weekly Weight Gain: Enter your desired gain, typically 0.25-0.5 kg (0.5-1 lb) per week for optimal muscle gain with minimal fat.
  7. (Optional) Enter Body Fat Percentage: If known, this can refine calculations but is not essential.
  8. Click 'Calculate Target Calories': The calculator will instantly display your BMR, TDEE, required calorie surplus, and your final target daily calorie intake for muscle gain.

How to read results:

  • BMR: The calories your body burns at complete rest.
  • TDEE: The total calories you burn daily, including activity.
  • Calorie Surplus: The additional calories needed each day to achieve your target weight gain.
  • Target Daily Calories: This is the key number – your daily caloric goal to fuel muscle growth.

Decision-making guidance: Use the "Target Daily Calories" as your primary nutritional guide. Aim to consistently consume this amount of calories daily through whole, nutrient-dense foods. Pay attention to macronutrient distribution (protein, carbs, fats) for optimal muscle protein synthesis and energy. Monitor your weight and physique changes weekly. If you are not gaining weight, slightly increase your calorie intake (e.g., by 200-300 kcal). If gaining too much fat, slightly decrease your intake or ensure your training intensity is sufficient. Remember, progressive overload in your resistance training is crucial for ensuring the gained weight is primarily muscle.

Key Factors That Affect Calorie Calculator Results

While the calorie calculator provides a solid estimate, several factors can influence your actual caloric needs for muscle gain:

  1. Metabolic Rate Variations: Individual metabolisms can differ significantly due to genetics, hormonal profiles (like thyroid function), and even muscle mass composition. Some individuals naturally burn more calories at rest than predicted by standard formulas.
  2. Exercise Intensity and Duration: The "Activity Level" chosen is an average. High-intensity interval training (HIIT), heavy compound lifting, or prolonged endurance activities can burn substantially more calories than moderate exercise, requiring adjustments to the TDEE estimate.
  3. Non-Exercise Activity Thermogenesis (NEAT): This refers to calories burned from daily movements outside of structured exercise, such as walking, fidgeting, and standing. A physically demanding job or a lifestyle with a lot of incidental movement increases NEAT and thus TDEE.
  4. Hormonal Status: Hormones like testosterone and growth hormone play a significant role in muscle protein synthesis. Factors influencing these hormones (e.g., sleep quality, stress levels, age) can indirectly affect how efficiently the body utilizes calories for muscle growth.
  5. Nutrient Timing and Composition: While total daily calories are paramount, the distribution of macronutrients (protein, carbohydrates, fats) and the timing of meals can influence muscle protein synthesis, recovery, and energy availability for workouts. A higher protein intake is generally recommended for muscle gain.
  6. Sleep Quality and Recovery: Inadequate sleep hinders muscle recovery and growth by disrupting hormonal balance (increasing cortisol, decreasing testosterone) and impairing protein synthesis. Poor sleep can also increase appetite for less healthy foods.
  7. Digestive Efficiency and Nutrient Absorption: Variations in gut health and digestive enzyme production can affect how well the body absorbs nutrients from food, potentially impacting the effective caloric intake.
  8. Age and Hormonal Changes: As individuals age, metabolic rates tend to decrease, and hormonal profiles change, which can affect muscle-building potential and caloric requirements.

Frequently Asked Questions (FAQ)

Q1: Can I gain muscle and lose fat simultaneously?

While it's challenging, it's possible, especially for beginners or individuals returning to training after a break. This process, often called "body recomposition," typically requires a modest calorie deficit or maintenance level with high protein intake and consistent, intense resistance training. Our calculator focuses on a surplus for *gaining* mass.

Q2: How much weight should I aim to gain per week?

For optimal muscle gain while minimizing fat accumulation, a target of 0.25 to 0.5 kg (approximately 0.5 to 1 lb) per week is generally recommended. Exceeding this rate often leads to a higher proportion of fat gain.

Q3: What if my TDEE calculation seems too high or too low?

These calculators provide estimates. Your true TDEE might differ. The best approach is to use the calculated target calories as a starting point, monitor your weight and body composition changes over 2-3 weeks, and adjust your intake accordingly. If you're not gaining, increase calories; if gaining too much fat, decrease slightly.

Q4: Do I need to count calories strictly forever?

Not necessarily. Once you understand your body's caloric needs and how different foods affect you, you can transition to more intuitive eating while still hitting your targets. However, for precise goals like significant muscle gain, tracking can be very beneficial, especially initially.

Q5: What role does protein play in muscle gain?

Protein provides the essential amino acids needed to repair and rebuild muscle tissue damaged during exercise. Adequate protein intake (typically 1.6-2.2 grams per kilogram of body weight) is crucial for maximizing muscle protein synthesis and ensuring the calories consumed are effectively used for muscle growth.

Q6: Can I use this calculator if I'm female?

Absolutely. The calculator includes a gender option, adapting the BMR calculation accordingly. Women can effectively gain muscle with the right caloric surplus and training, though hormonal differences may influence the rate and composition of weight gain compared to men.

Q7: What if I have a medical condition affecting my weight or metabolism?

If you have any medical conditions (e.g., thyroid issues, diabetes, eating disorders) or are taking medications that affect metabolism or appetite, consult with a healthcare professional or a registered dietitian before using this calculator or making significant dietary changes. This tool is for general informational purposes.

Q8: How long does it take to see results from a calorie surplus?

Visible muscle growth takes time and consistency. You might start noticing strength increases within a few weeks. Noticeable changes in muscle size and body composition typically become apparent after several weeks to months of consistent training and adherence to your calorie and protein targets.

© 2023 Your Fitness Hub. All rights reserved.

Disclaimer: This calculator provides estimates for informational purposes only. Consult with a healthcare professional or registered dietitian for personalized advice.

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goalWeightError.style.display = "none"; bodyFatPercentError.style.display = "none"; var isValid = true; if (isNaN(weight) || weight <= 0) { weightError.textContent = "Please enter a valid weight."; weightError.style.display = "block"; isValid = false; } if (isNaN(heightFeet) || isNaN(heightInches) || (heightFeet <= 0 && heightInches <= 0)) { heightError.textContent = "Please enter a valid height."; heightError.style.display = "block"; isValid = false; } if (isNaN(age) || age <= 0) { ageError.textContent = "Please enter a valid age."; ageError.style.display = "block"; isValid = false; } if (isNaN(goalWeightPerWeek) || goalWeightPerWeek <= 0) { goalWeightError.textContent = "Please enter a valid target gain."; goalWeightError.style.display = "block"; isValid = false; } if (!isNaN(bodyFatPercent) && (bodyFatPercent = 100)) { bodyFatPercentError.textContent = "Body fat percentage must be between 1 and 99%."; bodyFatPercentError.style.display = "block"; isValid = false; } if (!isValid) { return; } // Convert height to cm var heightCm = (heightFeet * 12 + heightInches) * 2.54; // Convert weight to kg var weightKg = weight; if (weight > 500) { // Assuming weight might be in lbs if very high weightKg = weight / 2.20462; } // Convert goal weight gain to kg var goalWeightKgPerWeek = goalWeightPerWeek; if (goalWeightPerWeek > 5) { // Assuming goalWeight might be in lbs if very high goalWeightKgPerWeek = goalWeightPerWeek / 2.20462; } var bmr = 0; if (gender === "male") { bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) + 5; } else { bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) – 161; } var tdee = bmr * activityLevel; // Calorie surplus for muscle gain: ~7700 kcal per kg of body mass. // For 0.5kg/week gain, that's 3850 kcal/week surplus, or 550 kcal/day. // We'll use a multiplier based on goalWeightKgPerWeek to make it dynamic. // A factor of ~550 per 0.5kg/week is roughly 1100 multiplier. var calorieSurplus = goalWeightKgPerWeek * 1100; var targetCalories = tdee + calorieSurplus; // — Macronutrient Calculation — var proteinGrams = 0; var carbGrams = 0; var fatGrams = 0; var proteinPercent = 0.35; // Example: 35% var carbPercent = 0.45; // Example: 45% var fatPercent = 0.20; // Example: 20% // Adjust percentages slightly based on body fat for leaner individuals if (!isNaN(bodyFatPercent) && bodyFatPercent 25) { proteinPercent = 0.30; // Slightly lower protein, higher carbs/fats if needed carbPercent = 0.50; fatPercent = 0.20; } // Ensure percentages add up to 100% var totalPercent = proteinPercent + carbPercent + fatPercent; if (totalPercent !== 1) { var adjustment = (1 – totalPercent) / 3; proteinPercent += adjustment; carbPercent += adjustment; fatPercent += adjustment; } proteinGrams = (targetCalories * proteinPercent) / 4; // 4 kcal per gram of protein carbGrams = (targetCalories * carbPercent) / 4; // 4 kcal per gram of carbs fatGrams = (targetCalories * fatPercent) / 9; // 9 kcal per gram of fat document.getElementById("bmrResult").textContent = bmr.toFixed(0); document.getElementById("tdeeResult").textContent = tdee.toFixed(0); document.getElementById("surplusResult").textContent = calorieSurplus.toFixed(0); document.getElementById("targetCalories").textContent = targetCalories.toFixed(0); document.getElementById("proteinGrams").textContent = proteinGrams.toFixed(0); document.getElementById("carbGrams").textContent = carbGrams.toFixed(0); document.getElementById("fatGrams").textContent = fatGrams.toFixed(0); updateChart(tdee.toFixed(0), targetCalories.toFixed(0)); } function resetCalculator() { document.getElementById("weight").value = "75"; document.getElementById("heightFeet").value = "5"; document.getElementById("heightInches").value = "10"; document.getElementById("age").value = "30"; document.getElementById("gender").value = "male"; document.getElementById("activityLevel").value = "1.55"; document.getElementById("goalWeight").value = "0.5"; document.getElementById("bodyFatPercent").value = ""; document.getElementById("bmrResult").textContent = "-"; document.getElementById("tdeeResult").textContent = "-"; document.getElementById("surplusResult").textContent = "-"; document.getElementById("targetCalories").textContent = "-"; document.getElementById("proteinGrams").textContent = "-"; document.getElementById("carbGrams").textContent = "-"; document.getElementById("fatGrams").textContent = "-"; // Clear errors document.getElementById("weightError").style.display = "none"; document.getElementById("heightError").style.display = "none"; document.getElementById("ageError").style.display = "none"; document.getElementById("goalWeightError").style.display = "none"; document.getElementById("bodyFatPercentError").style.display = "none"; // Clear chart var ctx = document.getElementById('calorieProjectionChart').getContext('2d'); ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height); ctx.font = "16px Segoe UI"; // Reset font for potential future labels } function copyResults() { var bmr = document.getElementById("bmrResult").textContent; var tdee = document.getElementById("tdeeResult").textContent; var surplus = document.getElementById("surplusResult").textContent; var target = document.getElementById("targetCalories").textContent; var protein = document.getElementById("proteinGrams").textContent; var carbs = document.getElementById("carbGrams").textContent; var fats = document.getElementById("fatGrams").textContent; var assumptions = "Activity Level: " + document.getElementById("activityLevel").options[document.getElementById("activityLevel").selectedIndex].text + "\n"; assumptions += "Target Weekly Gain: " + document.getElementById("goalWeight").value + " kg/week\n"; if (document.getElementById("bodyFatPercent").value) { assumptions += "Body Fat %: " + document.getElementById("bodyFatPercent").value + "%\n"; } var resultText = "— Muscle Gain Nutrition Plan —\n\n"; resultText += "Basal Metabolic Rate (BMR): " + bmr + " kcal\n"; resultText += "Total Daily Energy Expenditure (TDEE): " + tdee + " kcal\n"; resultText += "Calorie Surplus for Muscle Gain: " + surplus + " kcal\n"; resultText += "Target Daily Calories: " + target + "\n\n"; resultText += "— Example Macronutrient Split —\n"; resultText += "Protein: " + protein + "g\n"; resultText += "Carbohydrates: " + carbs + "g\n"; resultText += "Fats: " + fats + "g\n\n"; resultText += "— Key Assumptions —\n" + assumptions; navigator.clipboard.writeText(resultText).then(function() { // Optional: Provide user feedback, e.g., a temporary message var copyButton = document.querySelector('button.success'); copyButton.textContent = "Copied!"; setTimeout(function() { copyButton.textContent = "Copy Results"; }, 2000); }, function(err) { console.error('Could not copy text: ', err); // Fallback for browsers without clipboard API alert("Failed to copy. Please manually select and copy the results."); }); } // Charting Logic var calorieChart; // Declare globally function updateChart(tdee, targetCalories) { var ctx = document.getElementById('calorieProjectionChart').getContext('2d'); // Destroy previous chart instance if it exists if (calorieChart) { calorieChart.destroy(); } // Define chart dimensions – making it responsive within its container var chartWidth = ctx.canvas.parentElement.offsetWidth * 0.95; // Use 95% of parent width var chartHeight = chartWidth * 0.6; // Maintain aspect ratio ctx.canvas.width = chartWidth; ctx.canvas.height = chartHeight; // Basic chart configuration var labels = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']; var dataSeries1 = []; // TDEE var dataSeries2 = []; // Target Calories for (var i = 0; i < labels.length; i++) { dataSeries1.push(parseFloat(tdee)); dataSeries2.push(parseFloat(targetCalories)); } // Determine max value for consistent Y-axis scaling var maxValue = Math.max(tdee, targetCalories); var yAxisMax = maxValue * 1.15; // Add some padding calorieChart = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: [{ label: 'Estimated TDEE (kcal)', data: dataSeries1, borderColor: '#004a99', backgroundColor: 'rgba(0, 74, 153, 0.1)', fill: true, tension: 0.2 // Slight curve }, { label: 'Target Calories for Muscle Gain (kcal)', data: dataSeries2, borderColor: '#28a745', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: true, tension: 0.2 }] }, options: { responsive: true, maintainAspectRatio: false, // Disabled because we set width/height manually scales: { y: { beginAtZero: true, max: yAxisMax, // Set max for consistent scaling ticks: { callback: function(value) { return value + ' kcal'; } } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || ''; if (label) { label += ': '; } if (context.parsed.y !== null) { label += context.parsed.y.toFixed(0) + ' kcal'; } return label; } } }, legend: { position: 'top', } } } }); } // Initial calculation and chart render on load if defaults are present document.addEventListener('DOMContentLoaded', function() { // Add Chart.js library dynamically var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js'; script.onload = function() { calculateCalories(); // Calculate initial values based on defaults }; document.head.appendChild(script); // Initial reset to set sensible defaults and clear placeholder results resetCalculator(); // Then calculate based on defaults calculateCalories(); });

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