Calories to Gain Weight Calculator.net

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Calories to Gain Weight Calculator

Effortlessly calculate your daily caloric surplus needed for healthy weight gain and track your progress with our comprehensive tool.

Weight Gain Calorie Calculator

Enter your current weight.
Enter your desired weight.
0.5 lbs per week (Slow & Steady) 1 lb per week (Recommended) 1.5 lbs per week (Faster Gain) Choose how quickly you want to gain weight. 1 lb is approximately 3500 calories.
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 a week) Extra Active (very hard exercise/sports & physical job) Your average daily physical activity.
Harris-Benedict (Revised) Mifflin-St Jeor Choose the formula for Basal Metabolic Rate.
Male Female Select your gender for BMR calculation.
Your current age in years.
Your height in centimeters.

Your Weight Gain Strategy

Estimated Daily Caloric Intake for Weight Gain: — kcal
Total Weekly Caloric Surplus Needed: — kcal equivalent to about lbs/week
Estimated Basal Metabolic Rate (BMR): — kcal Calories burned at rest
Estimated Total Daily Energy Expenditure (TDEE): — kcal Calories burned with activity

We calculate your estimated TDEE using your BMR and activity level. To gain weight, you need to consume more calories than your TDEE. The formula used is: Daily Calorie Target = TDEE + (Weekly Caloric Surplus / 7) A surplus of 3500 calories approximates 1 lb of weight gain.

Projected Weight Gain Over Time

Visualizing your potential weight gain journey based on consistent caloric surplus.

Calorie & Macronutrient Breakdown

Nutrient Goal Estimated Daily Amount Notes
Target Calories — kcal Total daily intake for weight gain.
Protein — g Crucial for muscle building. Aim for 0.8-1g per lb of body weight.
Carbohydrates — g Primary energy source.
Fats — g Essential for hormone production and nutrient absorption.

What is a Weight Gain Calculator?

A calories to gain weight calculator is a powerful online tool designed to help individuals determine the specific number of daily calories they need to consume to achieve their weight gain goals in a healthy and sustainable manner. It bridges the gap between wanting to gain weight and understanding the precise nutritional strategy required. This calculator takes into account various personal factors to provide a personalized caloric target.

Who should use it? Individuals looking to increase their body mass, including those aiming to build muscle, recover from illness or eating disorders, or simply reach a healthier weight range. Athletes seeking to optimize performance and physique, and anyone struggling to maintain adequate weight due to a fast metabolism or high activity levels can benefit significantly from using this calculator. It's a starting point for anyone embarking on a weight gain journey.

Common misconceptions about weight gain: Many believe that simply eating more food, regardless of type, will lead to healthy weight gain. However, this often results in unhealthy fat accumulation rather than lean muscle mass. Another misconception is that weight gain must be slow; while a moderate pace is often recommended for muscle gain, understanding caloric needs is paramount. Some also underestimate the role of macronutrients (protein, carbs, fats) in the quality of weight gained.

Calories to Gain Weight Calculator Formula and Mathematical Explanation

The core principle behind gaining weight is consuming more calories than your body expends. This excess energy is stored, contributing to an increase in body mass. Our calculator uses a multi-step process to arrive at your target daily intake.

Step 1: Calculate Basal Metabolic Rate (BMR)

BMR is the number of calories your body burns at rest to maintain basic functions like breathing, circulation, and cell production. We use either the Revised Harris-Benedict Equation or the Mifflin-St Jeor Equation, depending on your selection:

  • Revised Harris-Benedict Equation (for men): BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) – (5.677 × age in years)
  • Revised Harris-Benedict Equation (for women): BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) – (4.330 × age in years)
  • Mifflin-St Jeor Equation (for men): BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
  • Mifflin-St Jeor Equation (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 accounts for your BMR plus the calories burned through physical activity. This is calculated by multiplying your BMR by an activity factor:

TDEE = BMR × Activity Factor

Step 3: Determine Caloric Surplus for Weight Gain

To gain weight, you need to eat more calories than your TDEE. A commonly accepted guideline is that a surplus of 3500 calories results in approximately 1 pound of weight gain. We adjust this based on your desired weekly gain rate:

Weekly Caloric Surplus = Desired Weight Gain Rate (lbs/week) × 3500 kcal/lb

Daily Caloric Surplus = Weekly Caloric Surplus / 7

Step 4: Calculate Target Daily Caloric Intake

Your final target is your TDEE plus the daily caloric surplus needed:

Daily Calorie Target = TDEE + Daily Caloric Surplus

Variables Table

Variable Meaning Unit Typical Range
Current Weight Your starting body weight. kg or lbs Varies greatly
Target Weight Your desired body weight. kg or lbs Varies greatly
Desired Weight Gain Rate How quickly you aim to gain weight. lbs per week 0.5 – 1.5 lbs/week
Activity Factor Multiplier based on daily physical activity. Unitless 1.2 – 1.9
Gender Biological sex used in BMR calculation. Male/Female Male or Female
Age Your age in years. Years 1 – 100+
Height Your physical stature. cm or inches Varies greatly
BMR Calories burned at rest. kcal Varies greatly
TDEE Total calories burned daily. kcal Varies greatly
Daily Calorie Target Total calories to consume daily for weight gain. kcal TDEE + Surplus

Practical Examples (Real-World Use Cases)

Example 1: Building Muscle Mass

Scenario: Sarah is a 25-year-old female, 5'7″ (170 cm), weighing 125 lbs (56.7 kg). She wants to build muscle and has a moderately active lifestyle (exercises 4 days a week). She aims to gain 1 lb per week.

Inputs:

  • Current Weight: 56.7 kg
  • Target Weight: 60.7 kg (aiming for a 10 lb gain)
  • Desired Weight Gain Rate: 1 lb per week
  • Activity Level: Moderately Active (1.55)
  • Gender: Female
  • Age: 25
  • Height: 170 cm
  • BMR Method: Mifflin-St Jeor

Calculation Breakdown:

  • BMR (Mifflin-St Jeor, Female): (10 * 56.7) + (6.25 * 170) – (5 * 25) – 161 = 567 + 1062.5 – 125 – 161 = 1343.5 kcal
  • TDEE: 1343.5 kcal * 1.55 = 2082.4 kcal
  • Weekly Caloric Surplus: 1 lb/week * 3500 kcal/lb = 3500 kcal
  • Daily Caloric Surplus: 3500 kcal / 7 days = 500 kcal
  • Daily Calorie Target: 2082.4 kcal (TDEE) + 500 kcal (Surplus) = 2582.4 kcal

Results: Sarah should aim for approximately 2583 kcal per day to gain about 1 lb per week. This includes a protein intake of roughly 100-113g for muscle synthesis.

Example 2: Healthy Weight Restoration

Scenario: John is a 40-year-old male, 5'10" (178 cm), weighing 140 lbs (63.5 kg). He needs to gain weight due to a recent illness and has a sedentary job. He aims for a moderate gain of 0.5 lbs per week.

Inputs:

  • Current Weight: 63.5 kg
  • Target Weight: 70 kg (aiming for a 16 lb gain)
  • Desired Weight Gain Rate: 0.5 lb per week
  • Activity Level: Sedentary (1.2)
  • Gender: Male
  • Age: 40
  • Height: 178 cm
  • BMR Method: Harris-Benedict (Revised)

Calculation Breakdown:

  • BMR (Harris-Benedict, Male): 88.362 + (13.397 * 63.5) + (4.799 * 178) – (5.677 * 40) = 88.362 + 850.80 + 854.22 – 227.08 = 1566.3 kcal
  • TDEE: 1566.3 kcal * 1.2 = 1879.6 kcal
  • Weekly Caloric Surplus: 0.5 lb/week * 3500 kcal/lb = 1750 kcal
  • Daily Caloric Surplus: 1750 kcal / 7 days = 250 kcal
  • Daily Calorie Target: 1879.6 kcal (TDEE) + 250 kcal (Surplus) = 2129.6 kcal

Results: John should aim for approximately 2130 kcal per day to gain about 0.5 lb per week. Focusing on nutrient-dense foods will be key for healthy weight restoration.

How to Use This Calories to Gain Weight Calculator

Using the calories to gain weight calculator is straightforward and requires just a few key pieces of information about yourself and your goals. Follow these simple steps:

  1. Enter Current Weight: Input your current body weight in kilograms or pounds. Ensure consistency in units.
  2. Enter Target Weight: Specify the weight you aim to achieve.
  3. Select Desired Gain Rate: Choose how many pounds per week you wish to gain. A rate of 0.5 to 1 lb per week is generally recommended for sustainable and healthier weight gain, particularly for muscle building.
  4. Choose Activity Level: Accurately assess your daily physical activity. This is crucial for calculating your Total Daily Energy Expenditure (TDEE).
  5. Select BMR Method: Choose between the Harris-Benedict or Mifflin-St Jeor equation for calculating your Basal Metabolic Rate. Both are widely used and reliable.
  6. Enter Gender, Age, and Height: Provide these basic biometric details for accurate BMR calculation.
  7. Click Calculate: Once all fields are filled, click the "Calculate" button.

How to Read Results

The calculator will display:

  • Estimated Daily Caloric Intake for Weight Gain: This is your primary target – the total number of calories you should aim to consume each day.
  • Total Weekly Caloric Surplus Needed: The total excess calories required over a week to meet your weight gain goal.
  • Estimated Basal Metabolic Rate (BMR): Calories burned at rest.
  • Estimated Total Daily Energy Expenditure (TDEE): Calories burned including your activity level.
  • Projected Weight Gain Chart: A visual representation of your potential progress.
  • Calorie & Macronutrient Breakdown: Suggested distribution of protein, carbs, and fats.

Decision-Making Guidance

Use the calculated daily calorie target as a starting point. Monitor your weight gain progress over a few weeks. If you are not gaining weight, slightly increase your daily intake (e.g., by 100-200 calories). If you are gaining weight too quickly or primarily gaining fat, slightly decrease your intake. Consult with a healthcare professional or registered dietitian for personalized advice, especially if you have underlying health conditions.

Key Factors That Affect Weight Gain Results

While the calculator provides a solid estimate, several real-world factors can influence your actual weight gain progress:

  1. Metabolic Rate Variations: Individual metabolisms can differ significantly. Some people naturally burn more calories than others, even with similar activity levels.
  2. Hormonal Balance: Hormones like thyroid hormones, insulin, and cortisol play a crucial role in metabolism and weight regulation. Imbalances can affect weight gain.
  3. Genetics: Your genetic makeup can influence your body composition, metabolism, and how efficiently you store energy.
  4. Digestive Health & Nutrient Absorption: Underlying digestive issues can impair your body's ability to absorb nutrients effectively, hindering weight gain even with adequate intake.
  5. Sleep Quality and Stress Levels: Poor sleep and high stress levels can negatively impact hormones that regulate appetite and metabolism (like ghrelin, leptin, and cortisol), potentially slowing down weight gain.
  6. Type of Food Consumed: While calories are key, the *quality* of calories matters. Nutrient-dense foods (lean proteins, complex carbs, healthy fats) support healthy tissue gain (muscle), whereas calorie-dense but nutrient-poor foods contribute more to fat gain.
  7. Consistency of Effort: Sporadic adherence to the calorie target and exercise plan will yield inconsistent results. Consistent daily effort is paramount for predictable weight gain.
  8. Muscle Protein Synthesis Rate: For muscle gain, the rate at which your body can synthesize muscle protein is a limiting factor, influenced by training stimulus, protein intake, and recovery.

Frequently Asked Questions (FAQ)

How accurate is this calculator?
The calculator provides an estimate based on widely accepted formulas and averages. Individual metabolic rates and responses can vary. It's a strong starting point, but monitoring your progress and adjusting intake is key.
What's the difference between gaining weight and gaining muscle?
Gaining weight refers to an increase in total body mass, which can include muscle, fat, and water. Gaining muscle specifically refers to increasing lean muscle tissue, which requires adequate protein intake, resistance training, and a caloric surplus. This calculator helps with the caloric surplus needed for overall weight gain, but muscle gain requires targeted training.
Can I gain weight too quickly?
Yes, gaining weight too rapidly (often more than 1-2 lbs per week) typically leads to a higher proportion of fat gain rather than muscle. It can also put unnecessary strain on your body. A slower, steadier pace is generally healthier and more sustainable for building quality mass.
Do I need to track macros (protein, carbs, fats)?
While calories are the primary driver of weight gain, tracking macronutrients is highly beneficial, especially if your goal is muscle gain. Ensuring sufficient protein intake is crucial for muscle repair and growth. The calculator provides estimated macro breakdowns as a guide.
What if my weight gain stalls?
If your weight gain stalls for more than a week or two, it likely means your body has adapted to your current intake, or your TDEE has increased slightly. Try increasing your daily calorie intake by another 100-200 calories and reassess. Ensure you are consistently tracking your food intake and activity.
Should I use this calculator if I want to gain fat?
This calculator helps determine the caloric surplus needed for weight gain in general. If your goal is specifically to gain fat, you would still need a caloric surplus, but the focus might shift away from protein and resistance training towards simply consuming excess calories, often from less healthy sources. However, for overall health, focusing on muscle gain is typically recommended.
Does exercise help with weight gain?
Yes, particularly resistance training (weightlifting). Exercise, especially strength training, signals your body to use the extra calories to build muscle tissue rather than just storing it as fat. It also increases appetite and contributes to your TDEE, requiring a higher calorie intake to achieve a surplus.
How do I convert between lbs and kg, or cm and inches?
1 kg = 2.20462 lbs. 1 inch = 2.54 cm. Ensure you use consistent units throughout the calculation. The calculator prompts for inputs in a specific unit (e.g., cm for height), but underlying calculations convert to metric where needed for formulas.
What if I have a medical condition affecting my weight?
If you have any medical conditions, particularly those related to metabolism, digestion, or hormonal balance (like thyroid issues, diabetes, or digestive disorders), it is crucial to consult a healthcare professional or a registered dietitian before attempting to gain weight. They can provide personalized guidance and ensure your strategy is safe and effective for your specific situation.
var chartInstance = null; // Global variable to hold the chart instance function showError(elementId, message) { var errorElement = document.getElementById(elementId + 'Error'); if (errorElement) { errorElement.innerText = message; } var inputElement = document.getElementById(elementId); if (inputElement) { inputElement.style.borderColor = '#dc3545'; } } function clearError(elementId) { var errorElement = document.getElementById(elementId + 'Error'); if (errorElement) { errorElement.innerText = "; } var inputElement = document.getElementById(elementId); if (inputElement) { inputElement.style.borderColor = '#ddd'; } } function isValidNumber(value) { return !isNaN(parseFloat(value)) && isFinite(value); } function calculateBMR(weightKg, heightCm, age, gender, method) { var bmr = 0; if (method === "harris-benedict") { if (gender === "male") { bmr = 88.362 + (13.397 * weightKg) + (4.799 * heightCm) – (5.677 * age); } else { // female bmr = 447.593 + (9.247 * weightKg) + (3.098 * heightCm) – (4.330 * age); } } else { // Mifflin-St Jeor if (gender === "male") { bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) + 5; } else { // female bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) – 161; } } return Math.round(bmr); } function calculateCalories() { var currentWeightInput = document.getElementById('currentWeight'); var targetWeightInput = document.getElementById('targetWeight'); var weightGainRateInput = document.getElementById('weightGainRate'); var activityLevelInput = document.getElementById('activityLevel'); var bmrMethodInput = document.getElementById('bmrMethod'); var genderInput = document.getElementById('gender'); var ageInput = document.getElementById('age'); var heightInput = document.getElementById('height'); var errors = false; // Input Validation var currentWeight = parseFloat(currentWeightInput.value); if (!isValidNumber(currentWeight) || currentWeight <= 0) { showError('currentWeight', 'Please enter a valid positive number for current weight.'); errors = true; } else { clearError('currentWeight'); } var targetWeight = parseFloat(targetWeightInput.value); if (!isValidNumber(targetWeight) || targetWeight <= 0) { showError('targetWeight', 'Please enter a valid positive number for target weight.'); errors = true; } else if (targetWeight <= currentWeight) { showError('targetWeight', 'Target weight must be greater than current weight.'); errors = true; } else { clearError('targetWeight'); } var weightGainRate = parseFloat(weightGainRateInput.value); if (isNaN(weightGainRate) || weightGainRate <= 0) { showError('weightGainRate', 'Please select a valid weight gain rate.'); errors = true; } else { clearError('weightGainRate'); } var activityLevel = parseFloat(activityLevelInput.value); if (isNaN(activityLevel) || activityLevel <= 0) { showError('activityLevel', 'Please select a valid activity level.'); errors = true; } else { clearError('activityLevel'); } var bmrMethod = bmrMethodInput.value; var gender = genderInput.value; var age = parseInt(ageInput.value); if (!isValidNumber(age) || age <= 0) { showError('age', 'Please enter a valid positive number for age.'); errors = true; } else { clearError('age'); } var height = parseFloat(heightInput.value); if (!isValidNumber(height) || height <= 0) { showError('height', 'Please enter a valid positive number for height in cm.'); errors = true; } else { clearError('height'); } if (errors) { document.getElementById('dailyCalorieTarget').innerText = '– kcal'; document.getElementById('weeklyCalorieSurplus').innerText = '– kcal'; document.getElementById('weeklyWeightGain').innerText = '–'; document.getElementById('estimatedBMR').innerText = '– kcal'; document.getElementById('estimatedTDEE').innerText = '– kcal'; updateTableAndChart('–', '–', '–', '–'); return; } // Conversion for calculations if needed (assuming metric for internal calc) var weightKg = currentWeight; var heightCm = height; // Add conversion logic if user can select lbs/inches and calculator needs kg/cm // For simplicity, assuming inputs are already in metric for now or that JS handles it if input types are 'number' // Calculations var bmr = calculateBMR(weightKg, heightCm, age, gender, bmrMethod); var tdee = bmr * activityLevel; var weeklyCalorieSurplus = weightGainRate * 3500; var dailyCalorieSurplus = weeklyCalorieSurplus / 7; var dailyCalorieTarget = tdee + dailyCalorieSurplus; // Macronutrient estimates (example: 30% protein, 40% carbs, 30% fats) // Protein: 1g per lb of *target* body weight is often recommended for muscle gain. // Let's use a general recommendation for simplicity: ~1.5g/kg of current weight for protein var proteinGrams = Math.round((dailyCalorieTarget * 0.30) / 4); // 30% protein var carbGrams = Math.round((dailyCalorieTarget * 0.40) / 4); // 40% carbs var fatGrams = Math.round((dailyCalorieTarget * 0.30) / 9); // 30% fats // Update results display document.getElementById('dailyCalorieTarget').innerText = Math.round(dailyCalorieTarget) + ' kcal'; document.getElementById('weeklyCalorieSurplus').innerText = Math.round(weeklyCalorieSurplus) + ' kcal'; document.getElementById('weeklyWeightGain').innerText = weightGainRate.toFixed(1); document.getElementById('estimatedBMR').innerText = Math.round(bmr) + ' kcal'; document.getElementById('estimatedTDEE').innerText = Math.round(tdee) + ' kcal'; updateTableAndChart(Math.round(dailyCalorieTarget), Math.round(proteinGrams), Math.round(carbGrams), Math.round(fatGrams)); updateChart(dailyCalorieTarget, tdee, bmr); // Pass values for chart update } function updateTableAndChart(targetCalories, protein, carbs, fats) { document.getElementById('tableTargetCalories').innerText = targetCalories === '–' ? '– kcal' : targetCalories + ' kcal'; document.getElementById('tableProtein').innerText = protein === '–' ? '– g' : protein + ' g'; document.getElementById('tableCarbs').innerText = carbs === '–' ? '– g' : carbs + ' g'; document.getElementById('tableFats').innerText = fats === '–' ? '– g' : fats + ' g'; } function updateChart(targetCalories, tdee, bmr) { var ctx = document.getElementById('weightGainChart').getContext('2d'); // Destroy previous chart instance if it exists if (chartInstance) { chartInstance.destroy(); } // Define approximate weeks for chart projection (e.g., 12 weeks) var weeksToProject = 12; var weightGainPerWeek = parseFloat(document.getElementById('weightGainRate').value); var dailySurplus = targetCalories – tdee; var weeklySurplus = dailySurplus * 7; var labels = []; var projectedCalories = []; // Placeholder for clarity, not directly plotted var projectedWeight = []; var tdeeValues = []; var bmrValues = []; var currentWeight = parseFloat(document.getElementById('currentWeight').value); if (isNaN(currentWeight) || currentWeight <= 0) currentWeight = 56.7; // Default if invalid for (var i = 0; i <= weeksToProject; i++) { labels.push('Week ' + i); var projectedWeightGain = (weightGainPerWeek * i); projectedWeight.push(currentWeight + projectedWeightGain); tdeeValues.push(tdee); // TDEE remains constant for this simplified chart bmrValues.push(bmr); // BMR remains constant projectedCalories.push(targetCalories); // Target calories remain constant } chartInstance = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: [ { label: 'Projected Weight (lbs)', data: projectedWeight, borderColor: 'rgb(75, 192, 192)', tension: 0.1, fill: false, pointRadius: 4, pointHoverRadius: 7 }, { label: 'TDEE (kcal)', data: tdeeValues, borderColor: 'rgb(255, 99, 132)', tension: 0.1, fill: false, borderDash: [5, 5], // Dashed line for TDEE pointRadius: 0 }, { label: 'BMR (kcal)', data: bmrValues, borderColor: 'rgb(54, 162, 235)', tension: 0.1, fill: false, borderDash: [2, 2], // Dotted line for BMR pointRadius: 0 } ] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: false, title: { display: true, text: 'Weight (lbs) / Calories (kcal)' } }, x: { title: { display: true, text: 'Time' } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || ''; if (label) { label += ': '; } if (context.parsed.y !== null) { if (context.dataset.label.includes('Weight')) { label += context.parsed.y.toFixed(1) + ' lbs'; } else { label += context.parsed.y.toFixed(0) + ' kcal'; } } return label; } } }, legend: { position: 'top', } } } }); } function resetForm() { document.getElementById('currentWeight').value = '70'; document.getElementById('targetWeight').value = '75'; document.getElementById('weightGainRate').value = '1'; document.getElementById('activityLevel').value = '1.55'; document.getElementById('bmrMethod').value = 'Mifflin-St Jeor'; document.getElementById('gender').value = 'male'; document.getElementById('age').value = '30'; document.getElementById('height').value = '175'; // Clear all errors clearError('currentWeight'); clearError('targetWeight'); clearError('weightGainRate'); clearError('activityLevel'); clearError('bmrMethod'); clearError('gender'); clearError('age'); clearError('height'); calculateCalories(); // Recalculate with default values } function copyResults() { var dailyTarget = document.getElementById('dailyCalorieTarget').innerText; var weeklySurplus = document.getElementById('weeklyCalorieSurplus').innerText; var weeklyGain = document.getElementById('weeklyWeightGain').innerText; var bmr = document.getElementById('estimatedBMR').innerText; var tdee = document.getElementById('estimatedTDEE').innerText; var tableTarget = document.getElementById('tableTargetCalories').innerText; var tableProtein = document.getElementById('tableProtein').innerText; var tableCarbs = document.getElementById('tableCarbs').innerText; var tableFats = document.getElementById('tableFats').innerText; var assumptions = "Assumptions:\n"; assumptions += "- Desired Gain Rate: " + document.getElementById('weightGainRate').options[document.getElementById('weightGainRate').selectedIndex].text + "\n"; assumptions += "- Activity Level: " + document.getElementById('activityLevel').options[document.getElementById('activityLevel').selectedIndex].text + "\n"; assumptions += "- BMR Method: " + document.getElementById('bmrMethod').value + "\n"; assumptions += "- Gender: " + document.getElementById('gender').value.charAt(0).toUpperCase() + document.getElementById('gender').value.slice(1) + "\n"; assumptions += "- Age: " + document.getElementById('age').value + "\n"; assumptions += "- Height: " + document.getElementById('height').value + " cm\n"; var textToCopy = "— Weight Gain Calculator Results —\n\n"; textToCopy += "Primary Goal:\n" + dailyTarget + "\n"; textToCopy += "Weekly Surplus: " + weeklySurplus + " (approx. " + weeklyGain + " lbs/week)\n"; textToCopy += "Estimated BMR: " + bmr + "\n"; textToCopy += "Estimated TDEE: " + tdee + "\n\n"; textToCopy += "Macronutrient Breakdown:\n"; textToCopy += "- Target Calories: " + tableTarget + "\n"; textToCopy += "- Protein: " + tableProtein + "\n"; textToCopy += "- Carbohydrates: " + tableCarbs + "\n"; textToCopy += "- Fats: " + tableFats + "\n\n"; textToCopy += assumptions; navigator.clipboard.writeText(textToCopy).then(function() { alert('Results copied to clipboard!'); }).catch(function(err) { console.error('Failed to copy: ', err); alert('Failed to copy results. Please copy manually.'); }); } // FAQ toggles document.addEventListener('DOMContentLoaded', function() { var faqItems = document.querySelectorAll('.faq-item .question'); faqItems.forEach(function(item) { item.addEventListener('click', function() { var parent = this.parentElement; parent.classList.toggle('open'); var answer = parent.querySelector('.answer'); if (parent.classList.contains('open')) { answer.style.display = 'block'; } else { answer.style.display = 'none'; } }); }); // Initial calculation on load resetForm(); // Load with sensible defaults and calculate });

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