Weight Planner Calculator

Weight Planner Calculator: Plan Your Weight Goals :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –border-color: #ddd; –card-background: #fff; –shadow: 0 2px 5px rgba(0,0,0,0.1); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: var(–background-color); color: var(–text-color); line-height: 1.6; margin: 0; padding: 0; } .container { max-width: 960px; margin: 20px auto; padding: 20px; background-color: var(–card-background); border-radius: 8px; box-shadow: var(–shadow); } h1, h2, h3 { color: var(–primary-color); text-align: center; margin-bottom: 1.5em; } h1 { font-size: 2.5em; } h2 { font-size: 1.8em; border-bottom: 2px solid var(–primary-color); padding-bottom: 0.5em; margin-top: 1.5em; } h3 { font-size: 1.4em; margin-top: 1.2em; } .loan-calc-container { background-color: var(–card-background); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-bottom: 30px; } .input-group { margin-bottom: 20px; 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Weight Planner Calculator

Welcome to the Weight Planner Calculator! This tool helps you set realistic weight goals, estimate timelines, and understand the key factors involved in your weight management journey. Whether you're aiming to lose, gain, or maintain weight, this calculator provides valuable insights to guide your efforts.

Weight Planning Tool

Enter your current body weight.
Enter your desired body weight.
0.5 kg/week (Slow & Sustainable) 1.0 kg/week (Moderate) 1.5 kg/week (Faster) -0.5 kg/week (Slow Gain) -1.0 kg/week (Moderate Gain) -1.5 kg/week (Faster Gain) Select your target rate of weight change per week.
Optional: Helps refine estimates.
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) Your typical daily physical activity.

Your Weight Plan Summary

Estimated time to reach target weight based on your inputs.
kg Weight to Change
kcal Estimated Daily Calorie Target
kcal Total Calorie Adjustment
Formula: Estimated Time = |Target Weight – Current Weight| / |Weekly Rate|
Estimated Daily Calorie Target = (Current Weight * BMR Factor) – (Weekly Rate * 7700)
(BMR Factor varies by activity level)
Weight Change Projection Table
Week Estimated Weight (kg) Estimated Calorie Target (kcal/day)

Weight & Calorie Trend Chart

Visualizing your projected weight and daily calorie target over time.

What is a Weight Planner Calculator?

A Weight Planner Calculator is a sophisticated online tool designed to help individuals set realistic and achievable weight management goals. It goes beyond simply stating a target weight; it provides a structured plan by estimating the time required to reach that goal based on a desired weekly rate of change. Furthermore, it offers crucial insights into the estimated daily calorie intake needed to achieve this rate, factoring in current weight, target weight, and activity levels. This weight planner calculator is an invaluable resource for anyone embarking on a journey to lose, gain, or maintain their body weight in a healthy and sustainable manner.

Who should use it? Anyone looking to manage their weight effectively can benefit. This includes individuals aiming for weight loss, those seeking to gain muscle or healthy weight, athletes optimizing their physique, or people simply wanting to maintain their current weight with a clear understanding of their caloric needs. It's particularly useful for those who want a data-driven approach rather than guesswork.

Common misconceptions about weight management often include the idea that drastic changes are necessary or that weight loss/gain is purely linear. This weight planner calculator helps counter these by emphasizing gradual, sustainable rates of change and providing personalized calorie targets. Another misconception is that activity level alone dictates calorie needs; this tool integrates it with weight goals for a more holistic view.

Weight Planner Calculator Formula and Mathematical Explanation

The core of the Weight Planner Calculator relies on fundamental principles of energy balance and metabolic rate estimation. The primary goal is to determine the time it takes to bridge the gap between current and target weight, and to estimate the daily caloric adjustments required.

Step 1: Calculate Total Weight Change Needed

This is the absolute difference between your current weight and your target weight.

Weight Change = |Target Weight - Current Weight|

Step 2: Estimate Time to Reach Target Weight

This is calculated by dividing the total weight change needed by the desired weekly rate of change. A key principle here is that approximately 7700 kcal deficit (for weight loss) or surplus (for weight gain) is needed to change body weight by 1 kilogram.

Estimated Time (Weeks) = Weight Change / |Desired Weekly Rate|

Step 3: Estimate Basal Metabolic Rate (BMR) or Resting Metabolic Rate (RMR)

While a precise BMR calculation requires more data (age, height, sex), this calculator uses a simplified approach by applying an activity factor to an estimated metabolic rate. The activity factors are approximations:

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

A simplified BMR estimate can be thought of as: Estimated BMR = Current Weight (kg) * Base Metabolic Factor (e.g., ~22-25 kcal/kg/day for general population). The calculator implicitly uses this by adjusting the calorie target based on activity.

Step 4: Estimate Daily Calorie Target

This is the most crucial part for planning. It involves adjusting the estimated daily energy expenditure to achieve the desired weekly weight change.

Estimated Daily Calorie Target = (Estimated Daily Energy Expenditure) - (Calories needed for weekly change)

Where:

  • Estimated Daily Energy Expenditure is approximated by multiplying current weight by an activity factor (e.g., Current Weight * Activity Factor).
  • Calories needed for weekly change = (Desired Weekly Rate * 7700 kcal) / 7 days. For a rate of 1 kg/week, this is (1 * 7700) / 7 = 1100 kcal/day deficit. For -1 kg/week (gain), it's a surplus of 1100 kcal/day.

Therefore, a simplified formula used by the calculator is:

Estimated Daily Calorie Target = (Current Weight * Activity Factor) - (Desired Weekly Rate * 1100)

Step 5: Calculate Total Calorie Adjustment

This is the total caloric deficit or surplus required over the entire estimated duration.

Total Calorie Adjustment = Weight Change * 7700 kcal

Variables Table

Variable Meaning Unit Typical Range
Current Weight Your starting body weight. kg 30 – 200+
Target Weight Your desired body weight. kg 30 – 200+
Desired Weekly Rate The rate at which you aim to change your weight each week. kg/week -1.5 to 1.5 (excluding 0)
Activity Level Your average daily physical activity. Categorical Sedentary, Light, Moderate, Very Active, Extra Active
Estimated Time Calculated duration to reach the target weight. Weeks Variable
Estimated Daily Calorie Target The daily calorie intake recommended to achieve the desired rate. kcal/day Variable
Total Calorie Adjustment The total caloric deficit or surplus needed for the entire weight change. kcal Variable
Body Fat Percentage Optional metric for context. % 5 – 60+

Practical Examples (Real-World Use Cases)

Let's explore how the Weight Planner Calculator can be used with practical scenarios:

Example 1: Weight Loss Goal

Scenario: Sarah wants to lose 10 kg. She currently weighs 75 kg and her target is 65 kg. She leads a moderately active lifestyle and aims for a sustainable weight loss of 0.75 kg per week.

Inputs:

  • Current Weight: 75 kg
  • Target Weight: 65 kg
  • Desired Weekly Rate: -0.75 kg/week
  • Activity Level: Moderately active

Calculator Output (Illustrative):

  • Weight to Change: 10 kg
  • Estimated Time: Approximately 13.3 weeks (10 kg / 0.75 kg/week)
  • Estimated Daily Calorie Target: Around 1700 kcal/day (Calculated based on moderate activity and a deficit to lose 0.75 kg/week)
  • Total Calorie Adjustment: 77,000 kcal (10 kg * 7700 kcal/kg)

Interpretation: Sarah needs to create a total deficit of 77,000 calories over roughly 13 weeks. This translates to a daily deficit of about 800 calories (7700 * 0.75 / 7), leading to an estimated daily intake of 1700 kcal if her maintenance is around 2500 kcal. This provides a clear roadmap.

Example 2: Weight Gain Goal

Scenario: Mark wants to gain 5 kg to build muscle. He currently weighs 70 kg and his target is 75 kg. He is very active with his training and wants to gain weight gradually at 0.5 kg per week.

Inputs:

  • Current Weight: 70 kg
  • Target Weight: 75 kg
  • Desired Weekly Rate: 0.5 kg/week
  • Activity Level: Very active

Calculator Output (Illustrative):

  • Weight to Change: 5 kg
  • Estimated Time: 10 weeks (5 kg / 0.5 kg/week)
  • Estimated Daily Calorie Target: Around 3100 kcal/day (Calculated based on very active lifestyle and a surplus to gain 0.5 kg/week)
  • Total Calorie Adjustment: 38,500 kcal (5 kg * 7700 kcal/kg)

Interpretation: Mark needs a total caloric surplus of 38,500 calories over 10 weeks. This means adding approximately 550 calories to his daily intake (7700 * 0.5 / 7), bringing his target to around 3100 kcal/day, assuming his maintenance is about 2550 kcal. This helps him structure his diet for muscle gain.

How to Use This Weight Planner Calculator

Using the Weight Planner Calculator is straightforward. Follow these steps to get your personalized weight plan:

  1. Enter Current Weight: Input your current body weight in kilograms.
  2. Enter Target Weight: Input your desired body weight in kilograms.
  3. Select Desired Weekly Rate: Choose how quickly you want to lose or gain weight. A rate between 0.5 kg and 1 kg per week is generally considered safe and sustainable for weight loss. For weight gain, 0.25 kg to 0.5 kg per week is often recommended.
  4. Input Optional Data: Provide your current body fat percentage (if known) and select your typical activity level. These help refine the calorie estimations.
  5. Calculate: Click the "Calculate Plan" button.

How to read results:

  • Estimated Time: This tells you how many weeks it might take to reach your goal at the specified rate.
  • Weight to Change: The total amount of weight you need to lose or gain.
  • Estimated Daily Calorie Target: This is your projected daily calorie intake to achieve the desired weekly rate. Remember, this is an estimate; your actual needs may vary.
  • Total Calorie Adjustment: The cumulative calorie deficit or surplus required.
  • Projection Table & Chart: These provide a week-by-week visual and tabular breakdown of your expected progress.

Decision-making guidance: Use the results to set realistic expectations. If the estimated time seems too long, consider if a slightly faster (but still safe) weekly rate is feasible, or if the target weight needs adjustment. The calorie target is your guide for daily intake – adjust your diet and exercise accordingly.

Key Factors That Affect Weight Planner Results

While the Weight Planner Calculator provides a solid estimate, several real-world factors can influence your actual progress:

  1. Metabolic Adaptation: As you lose weight, your metabolism can slow down slightly. Your body becomes more efficient, requiring fewer calories. This means your calorie target might need adjustment over time.
  2. Muscle Mass vs. Fat Mass: The calculator primarily tracks total weight. Gaining muscle while losing fat can sometimes mask fat loss on the scale, as muscle is denser than fat. Body composition changes are crucial beyond just the number on the scale.
  3. Hormonal Fluctuations: Hormones related to stress (cortisol), appetite (ghrelin, leptin), and thyroid function can significantly impact metabolism and appetite, affecting weight change rates.
  4. Dietary Adherence and Accuracy: The accuracy of your calorie tracking and adherence to your plan are paramount. Underestimating calorie intake or overestimating calorie expenditure can derail progress.
  5. Sleep Quality and Quantity: Poor sleep can disrupt hormones that regulate appetite and metabolism, potentially hindering weight loss or gain efforts and affecting energy levels.
  6. Hydration Levels: Water intake is vital for metabolic processes. Dehydration can sometimes be mistaken for hunger and can impact overall physical performance.
  7. Medications and Health Conditions: Certain medications (e.g., steroids, some antidepressants) and underlying health conditions (like PCOS or hypothyroidism) can affect weight and metabolism, requiring personalized medical advice.
  8. Digestive Health: The efficiency of nutrient absorption can vary, influencing how your body utilizes calories and affects weight changes.

Frequently Asked Questions (FAQ)

Is a 1 kg/week weight loss rate safe?
A rate of 0.5 to 1 kg per week is generally considered safe and sustainable for most individuals aiming for weight loss. Faster rates may be possible initially but can be harder to maintain and may lead to muscle loss. Always consult a healthcare professional for personalized advice.
What if my target weight is very different from my current weight?
If the difference is substantial, the estimated time might be long. Consider breaking down your goal into smaller, more manageable milestones. Also, ensure your target weight is healthy and realistic for your body frame and genetics. Consulting a doctor or registered dietitian is recommended.
How accurate is the calorie calculation?
The calorie calculation is an estimate based on general formulas and your provided activity level. Individual metabolic rates can vary significantly. This tool provides a starting point; you may need to adjust your intake based on your actual results.
Does this calculator account for exercise?
Yes, the 'Activity Level' input implicitly accounts for regular exercise. However, it doesn't calculate the specific calorie burn from individual workout sessions. For precise tracking, consider using a fitness tracker or logging your workouts separately.
What does a negative weekly rate mean?
A negative weekly rate (e.g., -0.5 kg/week) indicates a goal of weight gain. The calculator will adjust the estimated daily calorie target to suggest a caloric surplus needed to achieve this gain.
Can I use this calculator for body recomposition?
While this calculator focuses on weight change, body recomposition (losing fat while gaining muscle) is complex. The calculator can provide a baseline calorie target, but achieving recomposition often requires specific training, protein intake, and potentially cycling calories, which go beyond this tool's scope.
What if I don't know my activity level accurately?
Start with the level you believe is closest. Monitor your progress for a couple of weeks. If you're not seeing the expected changes, you may need to adjust your calorie intake slightly and reassess your activity level. It's often better to slightly underestimate activity if unsure.
How often should I update my inputs in the calculator?
As your weight changes, your metabolic rate and calorie needs will also change. It's advisable to recalculate your plan every 10-15% of weight lost or gained, or at least every few months, to ensure your targets remain relevant.

Related Tools and Internal Resources

© 2023 Your Website Name. All rights reserved. | Disclaimer: This calculator provides estimates for informational purposes only. Consult with a healthcare professional for personalized advice.
var currentWeightInput = document.getElementById('currentWeight'); var targetWeightInput = document.getElementById('targetWeight'); var weeklyRateSelect = document.getElementById('weeklyRate'); var bodyFatInput = document.getElementById('bodyFatPercentage'); var activityLevelSelect = document.getElementById('activityLevel'); var estimatedTimeDiv = document.getElementById('estimatedTime'); var weightDifferenceDiv = document.getElementById('weightDifference'); var estimatedWeeklyCaloriesDiv = document.getElementById('estimatedWeeklyCalories'); var estimatedTotalCaloriesDiv = document.getElementById('estimatedTotalCalories'); var projectionTableBody = document.querySelector('#projectionTable tbody'); var chart; var chartInstance = null; // To hold the Chart.js instance var activityFactors = { 'sedentary': 1.2, 'light': 1.375, 'moderate': 1.55, 'very_active': 1.725, 'extra_active': 1.9 }; var kcalPerKg = 7700; function validateInput(inputId, errorId, minValue, maxValue, allowZero = false) { var input = document.getElementById(inputId); var errorSpan = document.getElementById(errorId); var value = parseFloat(input.value); errorSpan.classList.remove('visible'); input.style.borderColor = '#ddd'; if (isNaN(value)) { errorSpan.textContent = 'Please enter a valid number.'; errorSpan.classList.add('visible'); input.style.borderColor = '#dc3545'; return false; } if (!allowZero && value === 0) { errorSpan.textContent = 'Value cannot be zero.'; errorSpan.classList.add('visible'); input.style.borderColor = '#dc3545'; return false; } if (value maxValue) { errorSpan.textContent = 'Value cannot be greater than ' + maxValue + '.'; errorSpan.classList.add('visible'); input.style.borderColor = '#dc3545'; return false; } return true; } function calculateWeightPlan() { var currentWeight = parseFloat(currentWeightInput.value); var targetWeight = parseFloat(targetWeightInput.value); var weeklyRate = parseFloat(weeklyRateSelect.value); var bodyFat = parseFloat(bodyFatInput.value); var activityLevel = activityLevelSelect.value; var isValid = true; isValid = validateInput('currentWeight', 'currentWeightError', 1) && isValid; isValid = validateInput('targetWeight', 'targetWeightError', 1) && isValid; isValid = validateInput('weeklyRate', 'weeklyRateError', -1.5, 1.5, true) && isValid; // Allow zero for rate if needed, but typically not for planning if (bodyFatInput.value !== ") { // Only validate if filled isValid = validateInput('bodyFatPercentage', 'bodyFatPercentageError', 0, 100) && isValid; } if (!isValid) { clearResults(); return; } var weightDifference = Math.abs(targetWeight – currentWeight); var estimatedTimeWeeks = weightDifference / Math.abs(weeklyRate); var estimatedTimeMonths = estimatedTimeWeeks / 4.33; // Approximate months var activityFactor = activityFactors[activityLevel] || 1.55; // Default to moderate // Simplified maintenance calories estimation: weight * activity factor // A more robust BMR formula (like Mifflin-St Jeor) would be better but requires age/height/sex. // This simplified approach assumes a base metabolic rate per kg and scales with activity. // Let's assume a base of ~22 kcal/kg for BMR, then multiply by activity factor. var estimatedMaintenanceCalories = (currentWeight * 22) * activityFactor; var weeklyCalorieChange = weeklyRate * kcalPerKg; var dailyCalorieAdjustment = weeklyCalorieChange / 7; var estimatedDailyCalorieTarget = estimatedMaintenanceCalories + dailyCalorieAdjustment; // Ensure calorie target is not excessively low or high, especially for gain if (weeklyRate > 0 && estimatedDailyCalorieTarget < 1200) estimatedDailyCalorieTarget = 1200; // Minimum for weight loss if (weeklyRate 4000) estimatedDailyCalorieTarget = 4000; // Cap for gain estimate var totalCalorieAdjustment = weightDifference * kcalPerKg; estimatedTimeDiv.textContent = estimatedTimeWeeks.toFixed(1) + " weeks (" + estimatedTimeMonths.toFixed(1) + " months)"; weightDifferenceDiv.textContent = weightDifference.toFixed(1); estimatedWeeklyCaloriesDiv.textContent = estimatedDailyCalorieTarget.toFixed(0); estimatedTotalCaloriesDiv.textContent = totalCalorieAdjustment.toFixed(0); updateProjectionTable(currentWeight, weeklyRate, estimatedDailyCalorieTarget, estimatedTimeWeeks); updateChart(currentWeight, targetWeight, estimatedTimeWeeks, estimatedDailyCalorieTarget, weeklyRate); } function clearResults() { estimatedTimeDiv.textContent = "–"; weightDifferenceDiv.textContent = "–"; estimatedWeeklyCaloriesDiv.textContent = "–"; estimatedTotalCaloriesDiv.textContent = "–"; projectionTableBody.innerHTML = "; if (chartInstance) { chartInstance.destroy(); chartInstance = null; } } function resetCalculator() { currentWeightInput.value = '70'; targetWeightInput.value = '65'; weeklyRateSelect.value = '1.0'; bodyFatInput.value = "; activityLevelSelect.value = 'moderate'; // Clear errors document.getElementById('currentWeightError').classList.remove('visible'); document.getElementById('targetWeightError').classList.remove('visible'); document.getElementById('weeklyRateError').classList.remove('visible'); document.getElementById('bodyFatPercentageError').classList.remove('visible'); document.getElementById('activityLevelError').classList.remove('visible'); currentWeightInput.style.borderColor = '#ddd'; targetWeightInput.style.borderColor = '#ddd'; weeklyRateSelect.style.borderColor = '#ddd'; bodyFatInput.style.borderColor = '#ddd'; calculateWeightPlan(); // Recalculate with defaults } function updateProjectionTable(startWeight, rate, startCalorieTarget, durationWeeks) { projectionTableBody.innerHTML = "; // Clear previous rows var currentWeight = startWeight; var currentCalorieTarget = startCalorieTarget; var weeklyCalorieChange = rate * kcalPerKg / 7; for (var i = 0; i 0 && currentCalorieTarget < 1200) currentCalorieTarget = 1200; if (rate 4000) currentCalorieTarget = 4000; } } function updateChart(startWeight, targetWeight, durationWeeks, startCalorieTarget, rate) { var ctx = document.getElementById('weightChart').getContext('2d'); // Destroy previous chart instance if it exists if (chartInstance) { chartInstance.destroy(); } var labels = ['Start']; var weightData = [startWeight]; var calorieData = [startCalorieTarget]; var currentWeight = startWeight; var currentCalorieTarget = startCalorieTarget; var weeklyCalorieChange = rate * kcalPerKg / 7; for (var i = 1; i 0 && currentCalorieTarget < 1200) currentCalorieTarget = 1200; if (rate 4000) currentCalorieTarget = 4000; weightData.push(currentWeight); calorieData.push(currentCalorieTarget); } // Add target weight point if duration is sufficient if (durationWeeks > 0 && durationWeeks <= 52) { labels.push('Target'); weightData.push(targetWeight); calorieData.push(currentCalorieTarget); // Use last calculated calorie target for target point } chartInstance = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: [{ label: 'Projected Weight (kg)', data: weightData, borderColor: 'rgb(75, 192, 192)', backgroundColor: 'rgba(75, 192, 192, 0.2)', fill: false, tension: 0.1 }, { label: 'Daily Calorie Target (kcal)', data: calorieData, borderColor: 'rgb(255, 99, 132)', backgroundColor: 'rgba(255, 99, 132, 0.2)', fill: false, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: false // Adjust based on data range } }, plugins: { tooltip: { mode: 'index', intersect: false } } } }); } function copyResults() { var mainResult = estimatedTimeDiv.textContent; var weightDiff = weightDifferenceDiv.textContent; var dailyCalTarget = estimatedWeeklyCaloriesDiv.textContent; var totalCalAdj = estimatedTotalCaloriesDiv.textContent; var assumptions = "Assumptions:\n"; assumptions += "- Current Weight: " + currentWeightInput.value + " kg\n"; assumptions += "- Target Weight: " + targetWeightInput.value + " kg\n"; assumptions += "- Weekly Rate: " + weeklyRateSelect.options[weeklyRateSelect.selectedIndex].text + "\n"; assumptions += "- Activity Level: " + activityLevelSelect.value + "\n"; if (bodyFatInput.value) { assumptions += "- Body Fat %: " + bodyFatInput.value + "%\n"; } var textToCopy = "— Weight Plan Summary —\n\n"; textToCopy += "Estimated Time: " + mainResult + "\n"; textToCopy += "Weight to Change: " + weightDiff + "\n"; textToCopy += "Estimated Daily Calorie Target: " + dailyCalTarget + "\n"; textToCopy += "Total Calorie Adjustment: " + totalCalAdj + "\n\n"; textToCopy += assumptions; // Use navigator.clipboard for modern browsers if (navigator.clipboard && navigator.clipboard.writeText) { navigator.clipboard.writeText(textToCopy).then(function() { alert('Results copied to clipboard!'); }).catch(function(err) { console.error('Failed to copy text: ', err); fallbackCopyTextToClipboard(textToCopy); }); } else { fallbackCopyTextToClipboard(textToCopy); } } function fallbackCopyTextToClipboard(text) { var textArea = document.createElement("textarea"); textArea.value = text; // Avoid scrolling to bottom textArea.style.top = "0"; textArea.style.left = "0"; textArea.style.position = "fixed"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'successful' : 'unsuccessful'; alert('Results copied to clipboard! (' + msg + ')'); } catch (err) { console.error('Fallback: Oops, unable to copy', err); alert('Failed to copy results. Please copy manually.'); } document.body.removeChild(textArea); } // Initialize FAQ toggles var faqQuestions = document.querySelectorAll('.faq-question'); faqQuestions.forEach(function(question) { question.addEventListener('click', function() { var faqItem = this.parentElement; faqItem.classList.toggle('open'); }); }); // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { // Load Chart.js library dynamically if not already present if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js@3.7.0/dist/chart.min.js'; // Use a specific version script.onload = function() { resetCalculator(); // Calculate after chart library is loaded }; script.onerror = function() { alert('Failed to load charting library. Chart features may be unavailable.'); resetCalculator(); // Calculate even if chart fails }; document.head.appendChild(script); } else { resetCalculator(); // Calculate immediately if Chart.js is already loaded } });

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