Calculate Calories Needed per Day to Lose Weight

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Calculate Your Daily Calorie Needs for Weight Loss

Daily Calorie Needs Calculator

Enter your current weight in kilograms (kg).
Enter your desired weight in kilograms (kg).
Enter your height in centimeters (cm).
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 a week) Extra Active (very hard exercise/sports & physical job)
Choose the option that best describes your typical physical activity.
0.25 kg/week (Slow & Steady) 0.5 kg/week (Recommended) 0.75 kg/week 1.0 kg/week (Aggressive)
Select how much weight you aim to lose per week.

Your Daily Calorie Target for Weight Loss

calories/day

Basal Metabolic Rate (BMR)

calories/day

Total Daily Energy Expenditure (TDEE)

calories/day

Caloric Deficit Needed

calories/day
How it's Calculated: Your Basal Metabolic Rate (BMR) is calculated using the Mifflin-St Jeor equation. This is then multiplied by your activity level factor to estimate your Total Daily Energy Expenditure (TDEE). Finally, a caloric deficit is subtracted from your TDEE to determine your daily calorie target for weight loss. A deficit of 500-750 calories per day generally leads to a loss of 0.5-0.75 kg per week.

Estimated Calorie Needs Over Time

Weight Loss Projection

What is Calculating Daily Calories Needed for Weight Loss?

Calculating your daily calorie needs for weight loss is a fundamental process that involves estimating how many calories your body burns each day and then creating a deficit to encourage fat loss. It's not about starvation, but about informed consumption. This calculation provides a personalized target to help you achieve your desired physique safely and effectively. It's a cornerstone of any successful weight management strategy, whether your goal is to shed a few pounds or achieve a significant transformation.

Who Should Use This Calculator?

Anyone looking to lose weight can benefit from this calorie calculator for weight loss. This includes:

  • Individuals starting a weight loss journey who need a starting point.
  • People who have hit a plateau and need to recalibrate their calorie intake.
  • Fitness enthusiasts looking to optimize their nutrition for fat loss.
  • Anyone seeking to understand the relationship between calorie intake and weight change.

Common Misconceptions About Calorie Needs for Weight Loss

Several myths surround calorie counting and weight loss. It's crucial to understand that simply eating very few calories is not sustainable or healthy. Crash dieting can lead to muscle loss, nutrient deficiencies, and a slowed metabolism. This calculator aims to provide a balanced approach, suggesting a deficit that allows for gradual, healthy weight loss. Remember, the quality of calories also matters – nutrient-dense foods provide essential vitamins and minerals that support overall health during weight loss.

Daily Calorie Needs for Weight Loss Formula and Mathematical Explanation

The process of calculating daily calorie needs for weight loss involves several steps, primarily based on estimating your Total Daily Energy Expenditure (TDEE) and then subtracting a deficit. The most common and scientifically accepted method uses the Mifflin-St Jeor equation to determine your Basal Metabolic Rate (BMR) and then applies an activity factor.

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. The Mifflin-St Jeor equation is widely considered more accurate than older formulas like Harris-Benedict:

  • 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 accounts for the calories burned through physical activity on top of your BMR. It's calculated by multiplying your BMR by an activity factor:

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

Step 3: Determine Caloric Deficit for Weight Loss

To lose weight, you need to consume fewer calories than your TDEE. A safe and sustainable rate of weight loss is typically 0.5 to 1 kg per week. Since approximately 7,700 calories equal 1 kg of fat, a deficit of 500-750 calories per day is generally recommended for a loss of 0.5-0.75 kg per week.

  • Caloric Deficit = Desired Weekly Weight Loss (in kg) × 7700 / 7 days
  • Daily Calorie Target = TDEE – Caloric Deficit

Variable Explanations and Table

Here's a breakdown of the variables used in the calculation:

Variable Meaning Unit Typical Range
Current Weight Your current body mass. Kilograms (kg) 20 – 200+
Target Weight Your desired body mass. Kilograms (kg) 20 – 200+
Height Your body's vertical measurement. Centimeters (cm) 50 – 210
Age Your age in years. Years 1 – 120
Gender Biological sex, affects BMR calculation. Male / Female Male, Female
Activity Level Average daily physical activity intensity. Factor (e.g., 1.2 – 1.9) 1.2, 1.375, 1.55, 1.725, 1.9
Desired Weekly Weight Loss Target rate of weight reduction. Kilograms per week (kg/week) 0.25 – 1.0
BMR Calories burned at rest. Kilocalories per day (kcal/day) 800 – 2500+
TDEE Total calories burned daily including activity. Kilocalories per day (kcal/day) 1200 – 4000+
Caloric Deficit Reduction in daily intake for weight loss. Kilocalories per day (kcal/day) 250 – 1000+
Daily Calorie Target Recommended daily intake for weight loss. Kilocalories per day (kcal/day) 1000 – 3000+

Practical Examples of Using the Calorie Calculator

Understanding how to use the calorie needs calculator is best illustrated with real-world scenarios. These examples show how different individuals can use the tool to set personalized weight loss goals.

Example 1: Sarah, Aiming for Gradual Weight Loss

Sarah is a 35-year-old female, 165 cm tall, weighing 70 kg. She wants to lose 5 kg and aims for a sustainable pace of 0.5 kg per week. She works a desk job but goes for a brisk walk 3-4 times a week, classifying her as 'Moderately Active'.

  • Inputs:
  • Current Weight: 70 kg
  • Target Weight: 65 kg
  • Height: 165 cm
  • Age: 35 years
  • Gender: Female
  • Activity Level: Moderately Active (1.55)
  • Desired Weekly Weight Loss: 0.5 kg/week

Calculated Results:

  • BMR: Approximately 1380 kcal/day
  • TDEE: Approximately 2139 kcal/day (1380 * 1.55)
  • Caloric Deficit: Approximately 500 kcal/day (0.5 * 7700 / 7)
  • Daily Calorie Target for Weight Loss: Approximately 1639 kcal/day

Interpretation: Sarah should aim to consume around 1640 calories per day to achieve her goal of losing 0.5 kg per week. This provides a clear nutritional target.

Example 2: Mark, Active Individual Seeking Faster Fat Loss

Mark is a 28-year-old male, 180 cm tall, weighing 85 kg. He has a physically demanding job and works out intensely 5-6 times a week, classifying him as 'Very Active'. He wants to lose 8 kg and is willing to aim for a slightly more aggressive loss of 0.75 kg per week.

  • Inputs:
  • Current Weight: 85 kg
  • Target Weight: 77 kg
  • Height: 180 cm
  • Age: 28 years
  • Gender: Male
  • Activity Level: Very Active (1.725)
  • Desired Weekly Weight Loss: 0.75 kg/week

Calculated Results:

  • BMR: Approximately 1846 kcal/day
  • TDEE: Approximately 3184 kcal/day (1846 * 1.725)
  • Caloric Deficit: Approximately 750 kcal/day (0.75 * 7700 / 7)
  • Daily Calorie Target for Weight Loss: Approximately 2434 kcal/day

Interpretation: Mark needs to consume approximately 2435 calories daily to support his high activity level while achieving a weight loss of 0.75 kg per week. This target helps ensure he has enough energy for his workouts and daily life.

How to Use This Daily Calorie Needs Calculator

Using our calorie needs calculator for weight loss is straightforward. Follow these simple steps to get your personalized daily calorie target:

Step-by-Step Instructions

  1. Enter Current Weight: Input your current body weight in kilograms (kg).
  2. Enter Target Weight: Input the weight you aim to achieve in kilograms (kg).
  3. Enter Height: Provide your height in centimeters (cm).
  4. Enter Age: Input your age in years.
  5. Select Gender: Choose 'Male' or 'Female' from the dropdown.
  6. Select Activity Level: Choose the option that best reflects your daily physical activity from 'Sedentary' to 'Extra Active'. Be honest for accurate results.
  7. Select Desired Weekly Weight Loss: Choose your target rate of weight loss (e.g., 0.5 kg/week is generally recommended for sustainability).
  8. Click Calculate: Press the 'Calculate' button to see your results.

How to Read Your Results

The calculator will display several key figures:

  • Your Daily Calorie Target for Weight Loss (Main Result): This is the primary number you should aim for daily to achieve your desired weight loss rate.
  • Basal Metabolic Rate (BMR): The calories your body burns at complete rest.
  • Total Daily Energy Expenditure (TDEE): Your estimated total daily calorie burn, including all activities.
  • Caloric Deficit Needed: The difference between your TDEE and your target intake, driving weight loss.

Decision-Making Guidance

Use your calculated Daily Calorie Target as a guideline. Focus on consuming nutrient-dense foods to feel full and satisfied. Remember that consistency is key. If you find the target difficult to maintain, consider adjusting your desired weekly weight loss rate to a slower, more sustainable pace. The included charts can help visualize your progress and potential timeline.

Key Factors Affecting Calorie Needs for Weight Loss

While our calorie calculator provides a solid estimate, several factors can influence your actual calorie needs and weight loss progress. Understanding these nuances can help you fine-tune your approach.

1. Body Composition (Muscle vs. Fat Mass)

Muscle tissue burns more calories at rest than fat tissue. If you have a higher muscle mass, your BMR will be higher, meaning you burn more calories even when inactive. This calculator uses general formulas, but individual body composition can lead to variations.

2. Metabolism Fluctuations

Metabolism isn't static. Factors like sleep quality, stress levels, hormonal changes (e.g., thyroid function), and even the thermic effect of food (calories burned digesting) can slightly alter your daily calorie expenditure.

3. Exercise Intensity and Type

While the 'Activity Level' factor is an estimate, the precise type, duration, and intensity of your workouts significantly impact calorie burn. High-intensity interval training (HIIT), for example, can lead to a greater "afterburn" effect (EPOC) than steady-state cardio.

4. Non-Exercise Activity Thermogenesis (NEAT)

NEAT includes all the calories burned from activities other than formal exercise, such as fidgeting, walking around the office, and household chores. This can vary significantly between individuals and significantly impact TDEE.

5. Dietary Thermogenesis

The process of digesting, absorbing, and metabolizing food burns calories. Protein has a higher thermic effect than carbohydrates or fats, meaning your body burns more calories digesting protein-rich meals.

6. Individual Biological Differences

Genetics play a role in metabolic rate. Some people naturally have a faster metabolism, while others have a slower one. Age also impacts metabolism, with it tending to slow down as we get older.

7. Consistency and Adherence

Perhaps the most crucial factor is sticking to your plan. Even the most accurate calorie calculation will fail if not followed consistently. Long-term adherence to a healthy eating pattern and activity level is paramount for sustained weight loss.

Frequently Asked Questions (FAQ)

Is a 500-calorie deficit per day always the best for weight loss?

A 500-calorie deficit per day is a common recommendation for a loss of about 0.5 kg per week, which is generally considered sustainable and healthy. However, the "best" deficit depends on your individual TDEE, starting weight, and lifestyle. For individuals with very high TDEEs or those needing to lose a significant amount of weight, a larger deficit might be appropriate, but extreme deficits can be counterproductive and lead to muscle loss or nutrient deficiencies. Always consult a healthcare professional for personalized advice.

What if my calculated target calorie intake seems too low?

If your target calorie intake falls below 1200 calories per day (for women) or 1500 calories per day (for men), it might be too low for sustained energy and nutrient intake. In such cases, consider a slightly slower weight loss rate (e.g., 0.25 kg/week) or focus on increasing your activity level to create a larger deficit without drastically cutting calories. Consulting a dietitian or nutritionist is highly recommended.

Does muscle weigh more than fat?

This is a common misconception. Muscle and fat have different densities, not weights. A pound of muscle takes up less space than a pound of fat. So, while a pound is a pound, muscle is more compact. When losing weight, especially through exercise, you might gain muscle while losing fat, which can sometimes make the number on the scale not change as rapidly as expected, even though your body composition is improving.

How does activity level affect my calorie needs?

Activity level significantly increases your Total Daily Energy Expenditure (TDEE). The more active you are, the more calories your body burns throughout the day. The calculator uses multipliers based on general activity levels. If your activity level is highly variable, it's best to take an average or adjust based on your most common routine.

Can I use this calculator if I'm trying to gain muscle?

This calculator is specifically designed for estimating calorie needs for weight loss. To gain muscle, you typically need a caloric surplus (eating more calories than you burn) combined with strength training. You would need a different type of calculator to determine your maintenance calories and then add a surplus.

What is the 7700 calorie rule for 1 kg of fat?

The "7700 calorie rule" is an approximation stating that approximately 7700 kilocalories (kcal) equate to 1 kilogram (kg) of body fat. This is based on the energy density of fat. While a useful guideline for estimating calorie deficits needed for weight loss, it's an average and individual results can vary due to metabolic adaptations and changes in body composition.

How often should I recalculate my calorie needs?

It's advisable to recalculate your calorie needs every 10-15 pounds (approx. 5-7 kg) of weight lost, or if your activity level changes significantly. As you lose weight, your BMR and TDEE decrease, so you may need to adjust your intake to continue losing weight at the same rate.

Does age affect BMR?

Yes, age is a factor in BMR calculations. Generally, BMR tends to decrease with age, particularly after age 30, due to natural declines in metabolic rate and muscle mass. The Mifflin-St Jeor equation accounts for this by including age as a variable.

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var ctxCalorieTrend; var calorieTrendChartInstance; var ctxWeightLoss; var weightLossChartInstance; // Initialize charts on load window.onload = function() { initializeCharts(); // Set default values for better user experience on load document.getElementById('currentWeight').value = 70; document.getElementById('targetWeight').value = 65; document.getElementById('height').value = 165; document.getElementById('age').value = 30; document.getElementById('gender').value = 'female'; document.getElementById('activityLevel').value = 'moderate'; document.getElementById('weightLossRate').value = 0.5; calculateCalories(); // Trigger calculation with defaults }; function initializeCharts() { // Calorie Trend Chart var calorieTrendCanvas = document.getElementById('calorieTrendChart'); if (calorieTrendCanvas) { ctxCalorieTrend = calorieTrendCanvas.getContext('2d'); calorieTrendChartInstance = new Chart(ctxCalorieTrend, { type: 'line', data: { labels: [], datasets: [{ label: 'Daily Calorie Target', data: [], borderColor: 'var(–primary-color)', backgroundColor: 'rgba(0, 74, 153, 0.1)', fill: true, tension: 0.1 }, { label: 'TDEE (Maintenance)', data: [], borderColor: 'var(–success-color)', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: false, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: false, title: { display: true, text: 'Calories per Day' } }, x: { title: { display: true, text: 'Weeks' } } }, plugins: { title: { display: true, text: 'Estimated Daily Calorie Target Over Time' } } } }); } // Weight Loss Projection Chart var weightLossCanvas = document.getElementById('weightLossChart'); if (weightLossCanvas) { ctxWeightLoss = weightLossCanvas.getContext('2d'); weightLossChartInstance = new Chart(ctxWeightLoss, { type: 'bar', // Using bar for discrete points data: { labels: [], datasets: [{ label: 'Projected Weight (kg)', data: [], backgroundColor: 'var(–primary-color)', borderColor: 'var(–primary-color)', borderWidth: 1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: false, title: { display: true, text: 'Weight (kg)' } }, x: { title: { display: true, text: 'Weeks' } } }, plugins: { title: { display: true, text: 'Projected Weight Loss Over Time' } } } }); } } function updateCharts(bmr, tdee, dailyTarget, currentWeight, targetWeight, weeklyLossRate) { var numWeeks = Math.ceil(Math.abs(currentWeight – targetWeight) / weeklyLossRate); var chartDataPoints = 10; // Number of points to show on the trend chart var weekInterval = Math.max(1, Math.floor(numWeeks / chartDataPoints)); var calorieLabels = []; var calorieTargetData = []; var tdeeData = []; var weightLabels = []; var weightData = []; var currentW = currentWeight; var avgTDEE = tdee; // Using initial TDEE as a reference for maintenance line for (var i = 0; i 1) { // Add the starting point if interval is large calorieLabels.unshift('Week 0'); tdeeData.unshift(avgTDEE); calorieTargetData.unshift(dailyTarget); weightLabels.unshift('Week 0'); weightData.unshift(currentWeight); } } // Add the final week if not already included if (numWeeks % weekInterval !== 0) { calorieLabels.push('Week ' + numWeeks); tdeeData.push(avgTDEE); calorieTargetData.push(dailyTarget); weightLabels.push('Week ' + numWeeks); weightData.push(targetWeight); } if (calorieTrendChartInstance) { calorieTrendChartInstance.data.labels = calorieLabels; calorieTrendChartInstance.data.datasets[0].data = calorieTargetData; calorieTrendChartInstance.data.datasets[1].data = tdeeData; calorieTrendChartInstance.options.plugins.title.text = 'Estimated Daily Calorie Target vs. TDEE'; calorieTrendChartInstance.update(); } if (weightLossChartInstance) { weightLossChartInstance.data.labels = weightLabels; weightLossChartInstance.data.datasets[0].data = weightData; weightLossChartInstance.options.plugins.title.text = 'Projected Weight Loss Path'; weightLossChartInstance.update(); } } function clearErrorMessages() { document.getElementById('currentWeightError').innerText = "; document.getElementById('targetWeightError').innerText = "; document.getElementById('heightError').innerText = "; document.getElementById('ageError').innerText = "; document.getElementById('genderError').innerText = "; document.getElementById('activityLevelError').innerText = "; document.getElementById('weightLossRateError').innerText = "; document.getElementById('currentWeightError').classList.remove('visible'); document.getElementById('targetWeightError').classList.remove('visible'); document.getElementById('heightError').classList.remove('visible'); document.getElementById('ageError').classList.remove('visible'); document.getElementById('genderError').classList.remove('visible'); document.getElementById('activityLevelError').classList.remove('visible'); document.getElementById('weightLossRateError').classList.remove('visible'); } function validateInput(id, min, max, errorMessage, isRequired = true) { var input = document.getElementById(id); var value = parseFloat(input.value); var errorDiv = document.getElementById(id + 'Error'); var isValid = true; if (isRequired && (input.value.trim() === " || isNaN(value))) { errorMessage = 'This field is required.'; isValid = false; } else if (!isNaN(value)) { if (value max) { errorMessage = 'Value cannot be greater than ' + max + '.'; isValid = false; } } if (!isValid) { errorDiv.innerText = errorMessage; errorDiv.classList.add('visible'); } else { errorDiv.innerText = "; errorDiv.classList.remove('visible'); } return isValid; } function calculateCalories() { clearErrorMessages(); var isValid = true; var currentWeight = parseFloat(document.getElementById('currentWeight').value); var targetWeight = parseFloat(document.getElementById('targetWeight').value); var height = parseFloat(document.getElementById('height').value); var age = parseInt(document.getElementById('age').value); var gender = document.getElementById('gender').value; var activityLevel = document.getElementById('activityLevel').value; var weightLossRate = parseFloat(document.getElementById('weightLossRate').value); var activityFactors = { sedentary: 1.2, light: 1.375, moderate: 1.55, very: 1.725, extra: 1.9 }; // Perform input validation if (!validateInput('currentWeight', 1, 500, 'Enter a valid current weight.')) isValid = false; if (!validateInput('targetWeight', 1, 500, 'Enter a valid target weight.')) isValid = false; if (!validateInput('height', 50, 250, 'Enter a valid height in cm.')) isValid = false; if (!validateInput('age', 1, 120, 'Enter a valid age.')) isValid = false; if (!validateInput('weightLossRate', 0.1, 2.0, 'Enter a valid weekly loss rate.')) isValid = false; // Allow some flexibility if (currentWeight <= targetWeight) { document.getElementById('targetWeightError').innerText = 'Target weight must be less than current weight.'; document.getElementById('targetWeightError').classList.add('visible'); isValid = false; } if (!isValid) { return; // Stop if any validation fails } // Calculate BMR (Mifflin-St Jeor Equation) var bmr; if (gender === 'male') { bmr = (10 * currentWeight) + (6.25 * height) – (5 * age) + 5; } else { // female bmr = (10 * currentWeight) + (6.25 * height) – (5 * age) – 161; } // Calculate TDEE var activityFactor = activityFactors[activityLevel]; var tdee = bmr * activityFactor; // Calculate Caloric Deficit var caloriesPerKgFat = 7700; var caloricDeficit = (weightLossRate * caloriesPerKgFat) / 7; // Calculate Daily Calorie Target var dailyCalorieTarget = tdee – caloricDeficit; // Ensure target is not excessively low var minSafeCalories = (gender === 'male' ? 1500 : 1200); if (dailyCalorieTarget < minSafeCalories) { dailyCalorieTarget = minSafeCalories; caloricDeficit = tdee – dailyCalorieTarget; // Recalculate deficit if target was adjusted // Optionally, inform user that target is capped at minSafeCalories } document.getElementById('results').style.display = 'block'; // Display results document.querySelector('.main-result .value').innerText = Math.round(dailyCalorieTarget); document.querySelector('.main-result .unit').innerText = 'calories/day'; document.querySelector('.result-item:nth-of-type(2) .value').innerText = Math.round(bmr); document.querySelector('.result-item:nth-of-type(2) .unit').innerText = 'calories/day'; document.querySelector('.result-item:nth-of-type(3) .value').innerText = Math.round(tdee); document.querySelector('.result-item:nth-of-type(3) .unit').innerText = 'calories/day'; document.querySelector('.result-item:nth-of-type(4) .value').innerText = Math.round(caloricDeficit); document.querySelector('.result-item:nth-of-type(4) .unit').innerText = 'calories/day'; // Update Charts updateCharts(bmr, tdee, dailyCalorieTarget, currentWeight, targetWeight, weightLossRate); } function resetCalculator() { document.getElementById('currentWeight').value = 70; document.getElementById('targetWeight').value = 65; document.getElementById('height').value = 165; document.getElementById('age').value = 30; document.getElementById('gender').value = 'female'; document.getElementById('activityLevel').value = 'moderate'; document.getElementById('weightLossRate').value = 0.5; clearErrorMessages(); document.getElementById('results').style.display = 'none'; // Clear chart data if (calorieTrendChartInstance) { calorieTrendChartInstance.data.labels = []; calorieTrendChartInstance.data.datasets.forEach(function(dataset) { dataset.data = []; }); calorieTrendChartInstance.update(); } if (weightLossChartInstance) { weightLossChartInstance.data.labels = []; weightLossChartInstance.data.datasets.forEach(function(dataset) { dataset.data = []; }); weightLossChartInstance.update(); } } function copyResults() { var mainResult = document.querySelector('.main-result .value').innerText; var mainUnit = document.querySelector('.main-result .unit').innerText; var bmrValue = document.querySelector('.result-item:nth-of-type(2) .value').innerText; var tdeeValue = document.querySelector('.result-item:nth-of-type(3) .value').innerText; var deficitValue = document.querySelector('.result-item:nth-of-type(4) .value').innerText; var currentWeight = document.getElementById('currentWeight').value; var targetWeight = document.getElementById('targetWeight').value; var height = document.getElementById('height').value; var age = document.getElementById('age').value; var gender = document.getElementById('gender').value; var activityLevel = document.getElementById('activityLevel').options[document.getElementById('activityLevel').selectedIndex].text; var weightLossRate = document.getElementById('weightLossRate').options[document.getElementById('weightLossRate').selectedIndex].text; var copyText = "— Daily Calorie Needs for Weight Loss Results —\n\n"; copyText += "Primary Target: " + mainResult + " " + mainUnit + "\n"; copyText += "Basal Metabolic Rate (BMR): " + bmrValue + " calories/day\n"; copyText += "Total Daily Energy Expenditure (TDEE): " + tdeeValue + " calories/day\n"; copyText += "Caloric Deficit Needed: " + deficitValue + " calories/day\n\n"; copyText += "— Key Assumptions —\n"; copyText += "Current Weight: " + currentWeight + " kg\n"; copyText += "Target Weight: " + targetWeight + " kg\n"; copyText += "Height: " + height + " cm\n"; copyText += "Age: " + age + " years\n"; copyText += "Gender: " + gender + "\n"; copyText += "Activity Level: " + activityLevel + "\n"; copyText += "Desired Weekly Weight Loss: " + weightLossRate + "\n"; var textArea = document.createElement("textarea"); textArea.value = copyText; textArea.style.position = "fixed"; textArea.style.opacity = 0; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied to clipboard!' : 'Failed to copy results.'; // Display feedback to user (optional, e.g., a temporary message) alert(msg); } catch (err) { alert('Oops, unable to copy. Please copy manually.'); } document.body.removeChild(textArea); } function toggleFaq(element) { var answer = element.nextElementSibling; answer.classList.toggle('visible'); } // Add event listeners for real-time updates (optional, can be triggered by button click too) document.getElementById('currentWeight').addEventListener('input', calculateCalories); document.getElementById('targetWeight').addEventListener('input', calculateCalories); document.getElementById('height').addEventListener('input', calculateCalories); document.getElementById('age').addEventListener('input', calculateCalories); document.getElementById('gender').addEventListener('change', calculateCalories); document.getElementById('activityLevel').addEventListener('change', calculateCalories); document.getElementById('weightLossRate').addEventListener('change', calculateCalories); // Chart.js library needs to be included for the charts to work. // Assuming you have included it via a CDN or local file. // For example: // If not included, the charts will not render. This is a critical dependency. // For this example to be fully functional, ensure Chart.js is loaded.

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