Fitwatch Com Weight Loss Calculator

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Estimate your weight loss journey based on calorie intake, expenditure, and activity levels.

Weight Loss Projection Calculator

Your Weight Loss Projection

Formula Used:

Weight loss is primarily driven by a calorie deficit. Approximately 3500 calories equal 1 pound (or 7700 calories equal 1 kilogram) of body fat. Your daily deficit is calculated as Daily Calorie Expenditure – Daily Calorie Intake. This is then used to determine weekly loss and time to goal.

Detailed Calculation Breakdown

Metric	Value	Unit
Current Weight	—	kg
Target Weight	—	kg
Weight to Lose	—	kg
Daily Calorie Intake	—	kcal
Daily Calorie Expenditure	—	kcal
Daily Calorie Deficit	—	kcal/day
Estimated Weekly Weight Loss	—	kg/week
Estimated Time to Goal	—	Weeks

What is the Fitwatch.com Weight Loss Calculator?

The Fitwatch.com Weight Loss Calculator is a sophisticated yet user-friendly tool designed to provide personalized projections for your weight loss journey. It operates on fundamental physiological principles, estimating the time it will take to achieve a specific weight loss goal based on your current weight, target weight, daily calorie intake, and daily calorie expenditure. Understanding your calorie deficit is the cornerstone of effective weight management, and this calculator breaks down the complex process into understandable metrics.

Who Should Use It?

This calculator is ideal for anyone embarking on a weight loss journey, whether they are a beginner or have prior experience. It’s beneficial for individuals looking to:

• Set realistic weight loss timelines.
• Understand the impact of their dietary habits and exercise routines.
• Quantify their daily calorie deficit.
• Make informed decisions about their fitness and nutrition plans.
• Track progress and stay motivated by seeing tangible estimates.

Common Misconceptions

Several misconceptions surround weight loss calculations:

• Instant Results: Many believe significant weight loss can happen in just a few days. Our calculator shows that sustainable weight loss takes time.
• One-Size-Fits-All: Assuming everyone loses weight at the same rate regardless of individual metabolism or lifestyle. The calculator accounts for variations in intake and expenditure.
• Focus Solely on Deficit: Ignoring the importance of nutrient quality, muscle mass, and overall health in favor of just cutting calories. While the calculator focuses on the calorie deficit, a balanced approach is crucial for health.
• Ignoring Maintenance: Thinking that once the goal weight is reached, the effort stops. Long-term success requires continued healthy habits.

Fitwatch.com Weight Loss Calculator Formula and Mathematical Explanation

The Fitwatch.com Weight Loss Calculator uses established principles of energy balance to project weight loss timelines. The core of the calculation revolves around the calorie deficit, which is the difference between the calories your body expends and the calories you consume.

Step-by-Step Derivation

1. Calculate Total Weight to Lose: This is the difference between your current weight and your target weight.
2. Determine Daily Calorie Deficit: This is calculated by subtracting your average daily calorie intake from your estimated total daily calorie expenditure.
3. Calculate Estimated Weekly Weight Loss: Since approximately 7700 calories equate to 1 kilogram of body fat (or 3500 calories for 1 pound), we divide the daily calorie deficit by 7700 and multiply by 7 (days in a week) to find the estimated weekly loss in kilograms.
4. Estimate Time to Reach Goal: Divide the total weight to lose by the estimated weekly weight loss.

Variable Explanations

The calculator utilizes several key variables:

• Current Weight: Your starting body weight.
• Target Weight: Your desired body weight goal.
• Daily Calorie Intake: The average number of calories consumed each day through food and beverages.
• Daily Calorie Expenditure: The total estimated number of calories burned per day. This is often estimated using Basal Metabolic Rate (BMR) multiplied by an activity level multiplier.
• Activity Level Multiplier: A factor that adjusts calorie expenditure based on your lifestyle and exercise frequency.

Variables Table

Variable	Meaning	Unit	Typical Range
Current Weight	Your present body mass.	kg	30 – 300+
Target Weight	Your desired body mass goal.	kg	30 – 300+
Daily Calorie Intake	Average calories consumed daily.	kcal	1000 – 4000+
Daily Calorie Expenditure	Total estimated calories burned daily (BMR x Activity Factor).	kcal	1500 – 5000+
Activity Level Multiplier	Factor for lifestyle intensity.	Unitless	1.2 – 1.9
Weight to Lose	Difference between current and target weight.	kg	1 – 100+
Daily Calorie Deficit	Calories burned minus calories consumed daily.	kcal/day	100 – 1500+
Weekly Weight Loss	Projected weight lost per week.	kg/week	0.1 – 2.0+
Time to Goal	Estimated duration to reach target weight.	Weeks	1 – 100+

Practical Examples (Real-World Use Cases)

Example 1: Steady Weight Loss Goal

Scenario: Sarah wants to lose 5 kg. She currently weighs 65 kg and aims for 60 kg. Her daily calorie intake averages 1700 kcal, and her estimated daily expenditure is 2200 kcal. She leads a moderately active lifestyle.

• Inputs:
  • Current Weight: 65 kg
  • Target Weight: 60 kg
  • Daily Calorie Intake: 1700 kcal
  • Daily Calorie Expenditure: 2200 kcal
  • Activity Level: Moderately Active (Multiplier 1.55 – this would be pre-selected or used to derive the 2200 kcal figure)
• Calculations:
  • Weight to Lose = 65 kg – 60 kg = 5 kg
  • Daily Calorie Deficit = 2200 kcal – 1700 kcal = 500 kcal/day
  • Estimated Weekly Weight Loss = (500 kcal/day * 7 days/week) / 7700 kcal/kg ≈ 0.45 kg/week
  • Estimated Time to Goal = 5 kg / 0.45 kg/week ≈ 11.1 weeks
• Interpretation: At this rate, Sarah can expect to reach her goal weight in just over 11 weeks if she consistently maintains her calorie intake and expenditure. This provides a tangible timeframe and helps manage expectations.

Example 2: Significant Weight Loss with Higher Deficit

Scenario: Mark weighs 90 kg and wants to reach 80 kg, a loss of 10 kg. He decides to increase his activity and is mindful of his diet, aiming for a larger deficit. His intake is 1900 kcal, and his expenditure is estimated at 2800 kcal. He is very active.

• Inputs:
  • Current Weight: 90 kg
  • Target Weight: 80 kg
  • Daily Calorie Intake: 1900 kcal
  • Daily Calorie Expenditure: 2800 kcal
  • Activity Level: Very Active (Multiplier 1.725)
• Calculations:
  • Weight to Lose = 90 kg – 80 kg = 10 kg
  • Daily Calorie Deficit = 2800 kcal – 1900 kcal = 900 kcal/day
  • Estimated Weekly Weight Loss = (900 kcal/day * 7 days/week) / 7700 kcal/kg ≈ 0.82 kg/week
  • Estimated Time to Goal = 10 kg / 0.82 kg/week ≈ 12.2 weeks
• Interpretation: Despite a larger daily deficit, the longer timeline is due to the greater amount of weight Mark needs to lose. This example highlights that while a higher deficit accelerates loss per week, the total duration depends on the overall goal. A deficit of 900 kcal/day is substantial and requires careful monitoring for sustainability and health.

How to Use This Fitwatch.com Weight Loss Calculator

Using the Fitwatch.com Weight Loss Calculator is straightforward and designed for immediate feedback. Follow these simple steps to get your personalized projection:

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, also in kilograms. Ensure your target weight is realistic and healthy for your body type.
3. Input Daily Calorie Intake: Accurately record the average number of calories you consume daily from all food and drinks. Consistency is key for accurate results.
4. Estimate Daily Calorie Expenditure: This is the total number of calories your body burns each day. You can estimate this using online calculators for Basal Metabolic Rate (BMR) and then multiplying by an appropriate activity level factor, or by inputting a pre-calculated value if known. The calculator also provides an activity level selector to help estimate this if you input your BMR.
5. Select Activity Level: If you haven’t directly entered your total daily expenditure, choose the option that best describes your general activity level (Sedentary, Lightly Active, Moderately Active, Very Active, Extra Active). This multiplier helps refine the calorie expenditure estimate.
6. Click ‘Calculate’: Once all fields are populated, click the ‘Calculate’ button.

How to Read Results

The calculator will display several key metrics:

• Estimated Weekly Weight Loss: This shows how many kilograms you are projected to lose each week based on your calorie deficit.
• Total Weight to Lose: The difference between your current and target weight.
• Estimated Time to Reach Goal: This is the projected number of weeks it will take to achieve your target weight.
• Daily Calorie Deficit: The difference between your daily expenditure and intake, indicating the net calorie loss per day.
• Detailed Breakdown Table: Provides a clear summary of all input values and calculated results for reference.
• Projected Weight Loss Chart: A visual representation of your expected weight loss over time.

Decision-Making Guidance

Use the results to inform your strategy:

• Realistic Goals: If the projected time is longer than you anticipated, consider if your calorie deficit is too small or if your target weight needs adjustment. A safe and sustainable rate of loss is typically 0.5-1 kg per week.
• Adjusting Intake/Expenditure: If the timeline is too long, you might need to slightly decrease your calorie intake or increase your physical activity to create a larger deficit. Conversely, if the loss seems too rapid or unsustainable, consider a smaller deficit.
• Motivation: Seeing the projected timeline and weekly loss can be a powerful motivator. Use this tool regularly to track progress and make adjustments as needed. Remember this is a projection; individual results may vary.

Key Factors That Affect Fitwatch.com Weight Loss Results

While the Fitwatch.com Weight Loss Calculator provides a solid projection based on calorie balance, numerous real-world factors can influence your actual weight loss journey. Understanding these can help you refine your approach and manage expectations:

1. Metabolic Adaptation: As you lose weight, your metabolism can slow down. Your body requires fewer calories to maintain a lower weight, meaning your calorie deficit might shrink over time, potentially slowing down weight loss.
2. Hormonal Fluctuations: Hormones like cortisol, thyroid hormones, and sex hormones can significantly impact metabolism, appetite, and fat storage, affecting weight loss progress independently of calorie balance.
3. Muscle Mass vs. Fat Mass: Weight loss calculations typically assume loss of fat. However, significant calorie restriction or intense exercise can lead to muscle loss, which is less metabolically active than fat and can skew the rate of scale change. Gaining muscle while losing fat can result in slower scale progress but improved body composition.
4. Water Retention: Fluctuations in hydration, sodium intake, carbohydrate consumption, and hormonal cycles (especially in women) can cause temporary changes in body weight due to water retention, masking underlying fat loss.
5. Sleep Quality and Quantity: Poor sleep is linked to increased appetite-regulating hormones (ghrelin and leptin imbalance), increased cravings for unhealthy foods, and reduced metabolic rate, all of which can hinder weight loss.
6. Stress Levels: Chronic stress can elevate cortisol levels, which promotes fat storage, particularly around the abdomen, and can increase appetite and cravings for high-calorie comfort foods.
7. Nutrient Timing and Composition: While the total daily calorie deficit is key, the *types* of food consumed (protein, fiber, healthy fats) and *when* they are eaten can impact satiety, energy levels, and muscle preservation, indirectly influencing adherence and results.
8. Medications and Health Conditions: Certain medications (e.g., some antidepressants, steroids) and underlying health conditions (e.g., hypothyroidism, PCOS) can affect metabolism and weight management.

Frequently Asked Questions (FAQ)

Q1: How accurate is the Fitwatch.com Weight Loss Calculator?

The calculator provides a projection based on the widely accepted principle of calorie deficit. It’s a good estimate for planning purposes. However, individual metabolic rates, hormonal responses, and lifestyle adherence can cause actual results to vary. It serves as a guide, not a guarantee.

Q2: What is a safe and sustainable rate of weight loss?

A safe and sustainable rate of weight loss is generally considered to be 0.5 to 1 kilogram (about 1 to 2 pounds) per week. This typically corresponds to a daily calorie deficit of 500 to 1000 calories. Faster loss is often unsustainable and can lead to muscle loss and other health issues.

Q3: My calculator shows I need to lose weight very slowly. What can I do?

If the projected time is very long, you might consider slightly increasing your daily calorie deficit. This can be achieved by reducing your calorie intake further (while ensuring nutritional adequacy) or increasing your physical activity (burning more calories). However, always prioritize health and sustainability over speed.

Q4: Does the calculator account for exercise calorie burn?

Yes, the ‘Daily Calorie Expenditure’ input is intended to represent your total daily burn, which includes your Basal Metabolic Rate (BMR) plus the calories burned through all physical activity, including planned exercise and non-exercise activity thermogenesis (NEAT). You can use the ‘Activity Level Multiplier’ option if you need help estimating this figure.

Q5: What does the ‘Activity Level Multiplier’ mean?

The Activity Level Multiplier is a factor used to estimate your total daily energy expenditure (TDEE) based on your Basal Metabolic Rate (BMR). It accounts for the calories burned through daily activities and planned exercise. Higher multipliers indicate more physical activity.

Q6: Should I aim for a large or small daily calorie deficit?

For most individuals, a moderate deficit of 500-750 calories per day is recommended for sustainable weight loss. Very large deficits (e.g., over 1000 calories) can be difficult to maintain, lead to nutrient deficiencies, muscle loss, and fatigue. Always consult with a healthcare professional or registered dietitian.

Q7: What if my target weight is higher than my current weight?

This calculator is primarily designed for weight loss projections. If your goal is weight gain, the principles are reversed (calorie surplus). You would need to adjust your intake and expenditure expectations accordingly, aiming for a calorie surplus rather than a deficit.

Q8: How often should I use this calculator?

It’s beneficial to use the calculator when you first set your goals, and then periodically (e.g., every 4-8 weeks) or whenever you make significant changes to your diet or exercise routine. This helps you reassess your progress and adjust your strategy if needed.

Related Tools and Internal Resources

• Basal Metabolic Rate (BMR) Calculator

  Understand your resting metabolic rate to better estimate your daily calorie expenditure.

• Online Calorie Tracker

  Log your daily food intake accurately to determine your average calorie consumption.

• Macronutrient Calculator

  Determine the optimal balance of protein, carbohydrates, and fats for your diet.

• Daily Water Intake Calculator

  Ensure you’re staying hydrated, a crucial component of overall health and weight management.

• BMI Calculator

  Calculate your Body Mass Index to get a general overview of your weight category.

• Exercise Calorie Calculator

  Estimate the calories burned during various physical activities.

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var targetWeightInput = document.getElementById(‘targetWeight’);
var dailyCaloriesInInput = document.getElementById(‘dailyCaloriesIn’);
var dailyCaloriesOutInput = document.getElementById(‘dailyCaloriesOut’);
var activityLevelInput = document.getElementById(‘activityLevel’);

var weeklyLossOutput = document.getElementById(‘weeklyLoss’);
var weightToLoseOutput = document.getElementById(‘weightToLose’);
var timeToGoalOutput = document.getElementById(‘timeToGoal’);
var dailyDeficitOutput = document.getElementById(‘dailyDeficit’);

var tableCurrentWeight = document.getElementById(‘tableCurrentWeight’);
var tableTargetWeight = document.getElementById(‘tableTargetWeight’);
var tableWeightToLose = document.getElementById(‘tableWeightToLose’);
var tableDailyCaloriesIn = document.getElementById(‘tableDailyCaloriesIn’);
var tableDailyCaloriesOut = document.getElementById(‘tableDailyCaloriesOut’);
var tableDailyDeficit = document.getElementById(‘tableDailyDeficit’);
var tableWeeklyLoss = document.getElementById(‘tableWeeklyLoss’);
var tableTimeToGoal = document.getElementById(‘tableTimeToGoal’);

var chartCanvas = document.getElementById(‘weightLossChart’);
var chartInstance = null;

var kgToLbs = 2.20462;
var caloriesPerKgFat = 7700; // Approximately 7700 kcal per kg of fat

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errorElement.innerText = ”;
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input.style.borderColor = '#dc3545';
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function updateChart() {
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var currentWeight = parseFloat(currentWeightInput.value);
var targetWeight = parseFloat(targetWeightInput.value);
var dailyCaloriesIn = parseFloat(dailyCaloriesInInput.value);
var dailyCaloriesOut = parseFloat(dailyCaloriesOutInput.value);

if (isNaN(currentWeight) || isNaN(targetWeight) || isNaN(dailyCaloriesIn) || isNaN(dailyCaloriesOut) || currentWeight <= targetWeight) {
// Don't draw chart if inputs are invalid or goal is already met/reversed
return;
}

var dailyDeficit = dailyCaloriesOut – dailyCaloriesIn;
if (dailyDeficit <= 0) {
// Not losing weight, clear chart
return;
}

var weeklyLossRate = (dailyDeficit * 7) / caloriesPerKgFat;
var weightToLose = currentWeight – targetWeight;
var totalWeeks = weightToLose / weeklyLossRate;

var labels = ['Start'];
var dataPoints = [currentWeight];
var weeksPassed = 0;

// Generate points for the chart, up to a reasonable limit (e.g., 50 weeks)
for (var i = 1; i <= Math.min(totalWeeks, 50); i++) {
weeksPassed++;
var weightAtWeek = currentWeight – (weeklyLossRate * weeksPassed);
labels.push('Week ' + weeksPassed);
dataPoints.push(weightAtWeek);
}
// Ensure the target weight is represented if it falls within the chart range
if (weeksPassed < totalWeeks && totalWeeks 50) {
labels.push(‘Week 50+’);
dataPoints.push(Math.max(targetWeight, currentWeight – (weeklyLossRate * 50))); // Show where they’d be at week 50
}

var ctx = chartCanvas.getContext(‘2d’);
chartInstance = new Chart(ctx, {
type: ‘line’,
data: {
labels: labels,
datasets: [{
label: ‘Projected Weight (kg)’,
data: dataPoints,
borderColor: ‘var(–primary-color)’,
backgroundColor: ‘rgba(0, 74, 153, 0.1)’,
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title: {
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text: ‘Weight (kg)’
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text: ‘Time’
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document.getElementById(‘dailyCaloriesInError’).innerText = ”;
document.getElementById(‘dailyCaloriesInError’).classList.remove(‘visible’);
document.getElementById(‘dailyCaloriesOutError’).innerText = ”;
document.getElementById(‘dailyCaloriesOutError’).classList.remove(‘visible’);
document.getElementById(‘activityLevelError’).innerText = ”;
document.getElementById(‘activityLevelError’).classList.remove(‘visible’);

var isValid = true;
if (!validateInput(‘currentWeight’, ‘currentWeightError’, 1, undefined, ‘Current Weight’)) isValid = false;
if (!validateInput(‘targetWeight’, ‘targetWeightError’, 1, undefined, ‘Target Weight’)) isValid = false;
if (!validateInput(‘dailyCaloriesIn’, ‘dailyCaloriesInError’, 1, undefined, ‘Daily Calorie Intake’)) isValid = false;
if (!validateInput(‘dailyCaloriesOut’, ‘dailyCaloriesOutError’, 1, undefined, ‘Daily Calorie Expenditure’)) isValid = false;

// Check if target is less than current weight specifically after validation
if(isValid && parseFloat(currentWeightInput.value) <= parseFloat(targetWeightInput.value)) {
document.getElementById('targetWeightError').innerText = 'Target weight must be less than current weight.';
document.getElementById('targetWeightError').classList.add('visible');
document.getElementById('targetWeight').style.borderColor = '#dc3545';
isValid = false;
}

if (!isValid) {
// Reset outputs if validation fails
weeklyLossOutput.innerText = '–';
weightToLoseOutput.innerText = '–';
timeToGoalOutput.innerText = '–';
dailyDeficitOutput.innerText = '–';
updateTableValues('–', '–', '–', '–', '–', '–', '–', '–');
if (chartInstance) chartInstance.destroy(); // Clear chart on invalid input
return;
}

var currentWeight = parseFloat(currentWeightInput.value);
var targetWeight = parseFloat(targetWeightInput.value);
var dailyCaloriesIn = parseFloat(dailyCaloriesInInput.value);
var dailyCaloriesOut = parseFloat(dailyCaloriesOutInput.value);

var weightToLose = currentWeight – targetWeight;
var dailyDeficit = dailyCaloriesOut – dailyCaloriesIn;

if (dailyDeficit <= 0) {
// User is not in a deficit, hence not losing weight
weeklyLossOutput.innerText = '0.0 kg';
weightToLoseOutput.innerText = weightToLose.toFixed(1) + ' kg';
timeToGoalOutput.innerText = 'N/A (No deficit)';
dailyDeficitOutput.innerText = dailyDeficit.toFixed(0) + ' kcal/day';
updateTableValues(currentWeight, targetWeight, weightToLose.toFixed(1), dailyCaloriesIn, dailyCaloriesOut, dailyDeficit.toFixed(0), '0.0', 'N/A');
if (chartInstance) chartInstance.destroy(); // Clear chart
return;
}

var weeklyLoss = (dailyDeficit * 7) / caloriesPerKgFat;
var timeToGoalWeeks = weightToLose / weeklyLoss;

weeklyLossOutput.innerText = weeklyLoss.toFixed(2) + ' kg';
weightToLoseOutput.innerText = weightToLose.toFixed(1) + ' kg';
timeToGoalOutput.innerText = timeToGoalWeeks.toFixed(1) + ' weeks';
dailyDeficitOutput.innerText = dailyDeficit.toFixed(0) + ' kcal/day';

updateTableValues(currentWeight, targetWeight, weightToLose.toFixed(1), dailyCaloriesIn, dailyCaloriesOut, dailyDeficit.toFixed(0), weeklyLoss.toFixed(2), timeToGoalWeeks.toFixed(1));

updateChart(); // Update chart with new data
}

function updateTableValues(cw, tw, wtl, cIn, cOut, dd, wl, ttg) {
tableCurrentWeight.innerText = cw === '–' ? '–' : cw.toFixed(1);
tableTargetWeight.innerText = tw === '–' ? '–' : tw.toFixed(1);
tableWeightToLose.innerText = wtl;
tableDailyCaloriesIn.innerText = cIn === '–' ? '–' : cIn;
tableDailyCaloriesOut.innerText = cOut === '–' ? '–' : cOut;
tableDailyDeficit.innerText = dd;
tableWeeklyLoss.innerText = wl;
tableTimeToGoal.innerText = ttg;
}

function resetCalculator() {
currentWeightInput.value = 70;
targetWeightInput.value = 65;
dailyCaloriesInInput.value = 1800;
dailyCaloriesOutInput.value = 2300;
activityLevelInput.value = '1.55'; // Default to Moderately Active

// Clear errors
document.getElementById('currentWeightError').innerText = '';
document.getElementById('currentWeightError').classList.remove('visible');
document.getElementById('targetWeightError').innerText = '';
document.getElementById('targetWeightError').classList.remove('visible');
document.getElementById('dailyCaloriesInError').innerText = '';
document.getElementById('dailyCaloriesInError').classList.remove('visible');
document.getElementById('dailyCaloriesOutError').innerText = '';
document.getElementById('dailyCaloriesOutError').classList.remove('visible');
document.getElementById('activityLevelError').innerText = '';
document.getElementById('activityLevelError').classList.remove('visible');

calculateWeightLoss(); // Recalculate with default values
}

function copyResults() {
var currentWeight = parseFloat(currentWeightInput.value);
var targetWeight = parseFloat(targetWeightInput.value);
var dailyCaloriesIn = parseFloat(dailyCaloriesInInput.value);
var dailyCaloriesOut = parseFloat(dailyCaloriesOutInput.value);
var activityLevelText = activityLevelInput.options[activityLevelInput.selectedIndex].text;

var weeklyLoss = weeklyLossOutput.innerText;
var weightToLose = weightToLoseOutput.innerText;
var timeToGoal = timeToGoalOutput.innerText;
var dailyDeficit = dailyDeficitOutput.innerText;

var resultText = "— Fitwatch.com Weight Loss Projection — \n\n";
resultText += "Assumptions:\n";
resultText += "- Current Weight: " + currentWeight.toFixed(1) + " kg\n";
resultText += "- Target Weight: " + targetWeight.toFixed(1) + " kg\n";
resultText += "- Daily Calorie Intake: " + dailyCaloriesIn + " kcal\n";
resultText += "- Daily Calorie Expenditure: " + dailyCaloriesOut + " kcal\n";
resultText += "- Activity Level: " + activityLevelText + "\n\n";
resultText += "— Results —\n";
resultText += "- Estimated Weekly Weight Loss: " + weeklyLoss + "\n";
resultText += "- Total Weight to Lose: " + weightToLose + "\n";
resultText += "- Estimated Time to Reach Goal: " + timeToGoal + "\n";
resultText += "- Daily Calorie Deficit: " + dailyDeficit + "\n";

// Use a temporary textarea to copy text
var textArea = document.createElement("textarea");
textArea.value = resultText;
textArea.style.position = "fixed"; // Avoid scrolling to bottom
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.';
// Optionally display a confirmation message to the user
var confirmation = document.createElement('div');
confirmation.textContent = msg;
confirmation.style.cssText = 'position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%); background-color: var(–primary-color); color: white; padding: 10px 20px; border-radius: 5px; z-index: 1000;';
document.body.appendChild(confirmation);
setTimeout(function() {
confirmation.remove();
}, 3000);
} catch (err) {
console.error('Fallback: Oops, unable to copy', err);
// Optionally display error message
} finally {
document.body.removeChild(textArea);
}
}

// Initialize chart and results on page load
document.addEventListener('DOMContentLoaded', function() {
// Add event listeners for real-time updates
currentWeightInput.addEventListener('input', calculateWeightLoss);
targetWeightInput.addEventListener('input', calculateWeightLoss);
dailyCaloriesInInput.addEventListener('input', calculateWeightLoss);
dailyCaloriesOutInput.addEventListener('input', calculateWeightLoss);
activityLevelInput.addEventListener('change', calculateWeightLoss);

// Initial calculation
calculateWeightLoss();
// Toggle FAQ answers
var faqQuestions = document.querySelectorAll('.faq-question');
faqQuestions.forEach(function(question) {
question.addEventListener('click', function() {
var answer = this.nextElementSibling;
answer.classList.toggle('visible');
});
});
});