Effortlessly plan your weight loss journey and discover a realistic timeline to reach your goal weight by a specific date. Our calculator helps you understand the science behind sustainable weight loss.
Weight Loss Planning Tool
Enter your current body weight.
Enter your target body weight.
Enter your target loss in kg or lbs per week. (0.5-1.0 kg/week is generally recommended).
Select today's date or the start of your journey.
Select your desired completion date.
Your Weight Loss Projection
—
—Total Weight to Lose
—Estimated Weeks Needed
—Adjusted Weekly Loss
Formula Explanation:
The total weight to lose is calculated by subtracting the goal weight from the current weight. The estimated weeks needed is determined by dividing the total weight to lose by the desired weekly loss rate. If the target date is sooner than the estimated weeks needed, an "Adjusted Weekly Loss" is calculated to show the actual rate required to meet the deadline.
Key Assumptions:
Projected weight loss over time.
Weight Loss Progress Table
Week
Date
Weight Remaining
Projected Weight
What is a Best Weight Loss by Date Calculator?
A Best Weight Loss by Date Calculator is a specialized online tool designed to help individuals set realistic weight loss targets and establish a feasible timeline for achieving them. It bridges the gap between a desired outcome (reaching a specific goal weight) and a desired timeframe (a target date), providing a quantifiable roadmap. Instead of simply aiming to "lose weight," this calculator allows you to work backward from a deadline, determining the necessary rate of weight loss and identifying potential challenges.
Who Should Use It?
This calculator is invaluable for anyone embarking on a weight loss journey who benefits from structure and clear milestones. It's particularly useful for individuals who:
Have a specific event (wedding, vacation, health screening) with a fixed date.
Struggle with motivation and need concrete targets to stay on track.
Want to understand the physiological demands of losing a certain amount of weight within a given period.
Are looking to set achievable goals based on safe and sustainable weight loss principles.
Common Misconceptions:
A prevalent misconception is that this calculator guarantees weight loss. It is a planning tool, not a magic wand. It doesn't account for individual metabolic differences, lifestyle adherence, or unexpected life events. Another misconception is that a faster calculated rate is always better. Rapid weight loss can be unsustainable and unhealthy; the calculator aims to find the *best* rate, which often means the *safest and most sustainable* rate within the given constraints. Effective weight loss requires consistent effort, dietary changes, and physical activity, which the calculator helps to contextualize.
Best Weight Loss by Date Calculator Formula and Mathematical Explanation
The core of the Best Weight Loss by Date Calculator relies on fundamental principles of weight management and time calculation. It helps determine the feasibility of a goal and, if necessary, adjusts the required effort.
Step-by-Step Derivation
Calculate Total Weight to Lose: This is the difference between your current weight and your goal weight.
Total Weight to Lose = Current Weight - Goal Weight
Calculate Total Days Available: Determine the number of days between the start date and the target date.
Total Days Available = Target Date - Start Date
Calculate Estimated Weeks Needed: Divide the total weight to lose by the desired weekly loss rate.
Estimated Weeks Needed = Total Weight to Lose / Desired Weekly Loss Rate
Calculate Total Weeks Available: Divide the total days available by 7.
Total Weeks Available = Total Days Available / 7
Determine Goal Feasibility and Adjusted Rate:
If Estimated Weeks Needed <= Total Weeks Available: Your goal is feasible with the desired rate. The calculator will show your desired weekly loss rate.
If Estimated Weeks Needed > Total Weeks Available: Your goal is not feasible with the desired rate. The calculator will calculate the necessary "Adjusted Weekly Loss" required to meet the target date.
Adjusted Weekly Loss = Total Weight to Lose / Total Weeks Available
Variable Explanations
The calculator utilizes the following variables:
Variable
Meaning
Unit
Typical Range
Current Weight
The starting body weight of the individual.
Kilograms (kg) or Pounds (lbs)
e.g., 50 – 200+ kg / 110 – 440+ lbs
Goal Weight
The target body weight the individual wishes to achieve.
Kilograms (kg) or Pounds (lbs)
e.g., 45 – 190+ kg / 100 – 420+ lbs (Should be less than Current Weight)
Desired Weekly Loss Rate
The user's intended pace of weight loss per week.
Kilograms (kg) or Pounds (lbs) per week
0.2 – 1.5 kg/week (0.5-1.0 kg/week is commonly recommended for sustainability)
Start Date
The date from which the weight loss plan begins.
Date
Present or past dates.
Target Date
The deadline by which the individual aims to reach their goal weight.
Date
Future dates.
Total Weight to Lose
The absolute amount of weight that needs to be shed.
Kilograms (kg) or Pounds (lbs)
Calculated value.
Total Days Available
The duration of the weight loss plan in days.
Days
Calculated value.
Total Weeks Available
The duration of the weight loss plan in weeks.
Weeks
Calculated value.
Estimated Weeks Needed
The number of weeks required to lose the target weight at the desired rate.
Weeks
Calculated value.
Adjusted Weekly Loss
The actual weekly weight loss rate required to meet the target date, if the desired rate is insufficient.
Kilograms (kg) or Pounds (lbs) per week
Calculated value.
Practical Examples (Real-World Use Cases)
Let's explore how the Best Weight Loss by Date Calculator can be applied in real-world scenarios.
Example 1: Wedding Season Preparation
Scenario: Sarah is getting married in 12 weeks and wants to lose 8 kg before her big day. She is currently 70 kg and her goal weight is 62 kg. She believes a loss of 0.75 kg per week is manageable.
Inputs:
Current Weight: 70 kg
Goal Weight: 62 kg
Desired Weekly Loss Rate: 0.75 kg/week
Start Date: Today (e.g., August 1, 2024)
Target Date: October 24, 2024 (12 weeks from start)
Adjusted Weekly Loss: 0.75 kg/week (since Estimated Weeks Needed is less than Total Weeks Available)
Sarah can confidently proceed with her goal, aiming for a weekly loss of 0.75 kg. The calculator confirms her plan is realistic for her wedding date. This provides clear direction for her diet and exercise regimen.
Example 2: Health Check-Up Deadline
Scenario: John needs to lose 10 kg for an important health screening in 8 weeks. He currently weighs 95 kg and wants to reach 85 kg. He initially hoped to lose weight at a rate of 0.5 kg per week.
Inputs:
Current Weight: 95 kg
Goal Weight: 85 kg
Desired Weekly Loss Rate: 0.5 kg/week
Start Date: Today (e.g., August 1, 2024)
Target Date: September 26, 2024 (8 weeks from start)
Primary Result: Your goal is not achievable at the desired rate.
Total Weight to Lose: 10 kg
Estimated Weeks Needed: 20 weeks
Adjusted Weekly Loss: 1.25 kg/week (calculated as 10 kg / 8 weeks)
John's initial plan of losing 0.5 kg per week is too slow for his 8-week deadline. The calculator shows he would need to achieve an Adjusted Weekly Loss of 1.25 kg per week to meet his health screening goal. This requires a more significant lifestyle change, prompting John to re-evaluate his strategy or potentially adjust his goal if the required loss rate is too aggressive or unhealthy for him. This insight is crucial for informed decision-making regarding his health journey.
How to Use This Best Weight Loss by Date Calculator
Using the Best Weight Loss by Date Calculator is straightforward and provides actionable insights into your weight management plans. Follow these simple steps to get started:
Enter Current Weight: Input your current body weight in kilograms (kg) or pounds (lbs). Ensure accuracy for the best results.
Enter Goal Weight: Input your target body weight. This should be less than your current weight.
Set Desired Weekly Loss Rate: Enter how much weight you aim to lose each week. A sustainable rate is typically between 0.5 kg to 1.0 kg (1-2 lbs) per week. Entering a rate that is too high may lead to unrealistic expectations or unhealthy practices.
Select Start Date: Choose the date when you are beginning your weight loss journey or when you want the calculation to start from.
Select Target Date: Choose the specific date by which you want to achieve your goal weight.
Click 'Calculate Timeline': The calculator will process your inputs and display the results instantly.
How to Read Results
Primary Highlighted Result: This tells you at a glance whether your goal is achievable within the specified timeframe and at your desired pace. It might say "Achievable!" or indicate that a faster rate is needed.
Total Weight to Lose: The total amount of weight (in kg or lbs) you need to shed to reach your goal.
Estimated Weeks Needed: How many weeks it would take to lose the required weight at your *desired* weekly loss rate.
Adjusted Weekly Loss: If your target date is sooner than the 'Estimated Weeks Needed', this value shows the *actual* weekly loss rate you must achieve to meet your deadline. This is a critical figure for understanding the intensity of effort required.
Key Assumptions: This section summarizes the core data used, such as the total weight to lose and the total weeks available, providing context for the results.
Progress Table and Chart: These visual aids show your projected weight at different points in time, helping you track progress and stay motivated.
Decision-Making Guidance
The results from the Best Weight Loss by Date Calculator should guide your decisions:
If Achievable: Congratulations! Maintain your desired weekly loss rate through consistent diet and exercise. Use the progress table and chart to stay on track.
If Not Achievable at Desired Rate: Review the 'Adjusted Weekly Loss'. If this rate is significantly higher than your desired rate and feels unsustainable or unhealthy, consider:
Adjusting your target date to be further in the future.
Slightly increasing your goal weight if feasible for your health.
Committing to a more intensive (but still safe) diet and exercise plan.
Consulting a healthcare professional or registered dietitian for personalized advice.
While the Best Weight Loss by Date Calculator provides a valuable projection, numerous real-world factors can influence the actual outcome. Understanding these is crucial for setting expectations and adapting your plan.
Metabolic Rate: Individual metabolic rates vary significantly. Factors like age, sex, muscle mass, and genetics influence how quickly your body burns calories. A slower metabolism might mean achieving a set weekly loss requires more effort than the calculator estimates.
Dietary Adherence and Calorie Deficit: The calculator assumes a consistent calorie deficit is maintained. Strict adherence to a healthy eating plan is paramount. Slip-ups, larger portion sizes, or increased calorie intake can negate planned losses. The calculator doesn't factor in the psychological aspect of sticking to a diet.
Physical Activity Level: While not explicitly a calculator input, exercise significantly impacts calorie expenditure. Increasing activity can accelerate weight loss beyond the base projection or make it easier to achieve the required rate. Conversely, reduced activity will slow progress. [Consider linking to Exercise Benefits for Weight Loss].
Hormonal Fluctuations and Health Conditions: Conditions like PCOS, thyroid issues, or hormonal changes (e.g., menopause, stress-related cortisol) can dramatically affect weight loss. These physiological factors are complex and not quantifiable by a simple calculator.
Water Retention: Short-term fluctuations in weight are often due to water retention caused by high sodium intake, hormonal cycles, or intense exercise. These can temporarily mask fat loss on the scale, even if the underlying fat reduction is occurring.
Sleep Quality and Stress Levels: Poor sleep and high stress levels can disrupt hormones that regulate appetite and fat storage (like ghrelin, leptin, and cortisol), potentially hindering weight loss efforts. Managing stress and prioritizing sleep are vital components of a successful journey.
Muscle Gain vs. Fat Loss: If engaging in strength training, you might gain muscle mass while losing fat. Muscle is denser than fat, so the scale might not reflect the body composition changes accurately. The calculator focuses purely on weight reduction. [Explore Body Composition Analysis].
Medications: Certain medications can cause weight gain or make weight loss more challenging as a side effect. It's essential to discuss any potential impact with your doctor.
Always consult with a healthcare professional or a registered dietitian for personalized advice tailored to your unique health status and goals. They can help you interpret results and create a safe, effective weight loss plan.
Frequently Asked Questions (FAQ)
Q1: Is a 1 kg (2.2 lbs) per week weight loss rate healthy?
A rate of 0.5 to 1.0 kg (1-2 lbs) per week is generally considered safe and sustainable for most individuals. Losing weight faster than this can lead to muscle loss, nutrient deficiencies, and is often harder to maintain long-term. The calculator helps determine if your desired rate is feasible for your timeline.
Q2: What should I do if my target date is too soon for my weight loss goal?
If the calculator shows your goal isn't achievable by your target date at a safe rate, you have a few options: extend your target date, aim for a slightly higher goal weight (if medically appropriate), or commit to a more intensive, yet safe, diet and exercise plan. Consulting a healthcare provider is recommended.
Q3: Does the calculator account for metabolic adaptation?
No, this calculator uses a static calculation based on initial inputs. As you lose weight, your metabolism may slow down (metabolic adaptation), meaning you might need to adjust your calorie intake or activity level to continue losing weight at the same rate. The calculator provides an estimate, not a guaranteed outcome.
Q4: Can I use different units (kg vs. lbs) in the calculator?
The calculator is designed to work with consistent units throughout. If you input your current and goal weights in kilograms, the weekly loss rate should also be in kilograms per week. If you use pounds, ensure the weekly rate is in pounds per week. The calculator assumes consistent unit usage for all relevant fields.
Q5: What if my goal weight is higher than my current weight?
The calculator is designed for weight loss, meaning the goal weight should be less than the current weight. If you input a goal weight higher than your current weight, the calculation for "Total Weight to Lose" will be negative, and the results may not be meaningful. Please ensure your goal weight reflects a reduction from your current weight.
Q6: How accurate is the projected weight loss chart?
The chart shows a linear projection based on the calculated weekly loss rate. Real-world weight loss is rarely perfectly linear due to factors like water retention, hormonal changes, and adherence fluctuations. The chart serves as a visual guide and motivator, illustrating the potential path towards your goal.
Q7: Do I need to consult a doctor before using this calculator?
While this calculator is a planning tool, it's always recommended to consult with a healthcare professional before starting any significant weight loss program, especially if you have underlying health conditions. They can provide personalized advice and ensure your goals are healthy and achievable.
Q8: How does this calculator differ from a simple weight loss goal setting?
This calculator specifically links your weight loss goal to a target date. It not only tells you *how much* weight to lose but also *how quickly* you need to lose it to meet that deadline. This temporal component adds a layer of accountability and realism, helping you understand the demands of your goal. It also calculates an adjusted rate if the initial desired pace is insufficient.
Understanding MetabolismLearn about factors affecting your metabolic rate and how to optimize it.
var primaryResultElement = document.getElementById('primaryResult');
var totalWeightToLoseElement = document.getElementById('totalWeightToLoseContainer').querySelector('strong');
var estimatedWeeksElement = document.getElementById('estimatedWeeksContainer').querySelector('strong');
var actualWeeklyLossElement = document.getElementById('actualWeeklyLossContainer').querySelector('strong');
var keyAssumptionsElement = document.getElementById('keyAssumptions');
var resultsDiv = document.getElementById('results');
var progressTableBody = document.getElementById('progressTableBody');
var weightLossChartCanvas = document.getElementById('weightLossChart');
var chartInstance = null; // Variable to hold the chart instance
// Default Units – assuming metric (kg) for calculation logic clarity, but UI should adapt
// For simplicity in this implementation, we'll assume consistent units are used by the user.
// A more robust version would include unit selection and conversion.
function calculateWeightLoss() {
// Clear previous errors
clearErrors();
// Get input values
var currentWeight = parseFloat(document.getElementById('currentWeight').value);
var goalWeight = parseFloat(document.getElementById('goalWeight').value);
var weeklyLossRate = parseFloat(document.getElementById('weeklyLossRate').value);
var currentDate = document.getElementById('currentDate').value;
var goalDate = document.getElementById('goalDate').value;
// — Input Validation —
var isValid = true;
if (isNaN(currentWeight) || currentWeight <= 0) {
document.getElementById('currentWeightError').innerText = 'Please enter a valid current weight.';
document.getElementById('currentWeightError').style.display = 'block';
isValid = false;
}
if (isNaN(goalWeight) || goalWeight <= 0) {
document.getElementById('goalWeightError').innerText = 'Please enter a valid goal weight.';
document.getElementById('goalWeightError').style.display = 'block';
isValid = false;
}
if (isNaN(weeklyLossRate) || weeklyLossRate <= 0) {
document.getElementById('weeklyLossRateError').innerText = 'Please enter a valid desired weekly loss rate (e.g., 0.5).';
document.getElementById('weeklyLossRateError').style.display = 'block';
isValid = false;
}
if (currentWeight 1.5) { // A common recommended upper limit for safe loss
document.getElementById('weeklyLossRateError').innerText = 'A weekly loss rate above 1.5 is often unsustainable and potentially unhealthy.';
document.getElementById('weeklyLossRateError').style.display = 'block';
// Don't set isValid to false here, allow user to proceed but warn them
}
if (currentDate === "") {
document.getElementById('currentDateError').innerText = 'Please select a start date.';
document.getElementById('currentDateError').style.display = 'block';
isValid = false;
}
if (goalDate === "") {
document.getElementById('goalDateError').innerText = 'Please select a target date.';
document.getElementById('goalDateError').style.display = 'block';
isValid = false;
}
var startDateObj = new Date(currentDate);
var goalDateObj = new Date(goalDate);
// Adjust dates to midnight to ensure correct day difference calculation
startDateObj.setHours(0, 0, 0, 0);
goalDateObj.setHours(0, 0, 0, 0);
if (goalDateObj <= startDateObj) {
document.getElementById('goalDateError').innerText = 'Target date must be after the start date.';
document.getElementById('goalDateError').style.display = 'block';
isValid = false;
}
if (!isValid) {
resultsDiv.style.display = 'none';
return;
}
// — Calculations —
var totalWeightToLose = currentWeight – goalWeight;
var timeDiff = goalDateObj.getTime() – startDateObj.getTime();
var totalDaysAvailable = Math.ceil(timeDiff / (1000 * 3600 * 24));
var totalWeeksAvailable = totalDaysAvailable / 7;
var estimatedWeeksNeeded = totalWeightToLose / weeklyLossRate;
var primaryResultText = "";
var adjustedWeeklyLoss = 0;
var assumptions = "Current Weight: " + currentWeight + " units, Goal Weight: " + goalWeight + " units, Target Date: " + goalDate + ". ";
if (estimatedWeeksNeeded 52 ? 2 : 1; // Adjust increment for longer/shorter timelines
// Ensure we don't have infinite loop for edge cases
var safetyBreak = 0;
var maxSafetyIterations = 500; // Arbitrary large number
for (var i = 0; i <= maxWeeks + weekIncrement && safetyBreak = maxWeeks) { // Add points for start, end, and increments
dataPoints.push({ week: weeksPassed, weight: projectedWeight, date: formattedDate });
}
if (weeksPassed >= maxWeeks && projectedWeight endDate && projectedWeight > goalWeight) break; // Stop if time elapsed but goal not met
safetyBreak++;
}
// Ensure the goal weight and target date are represented if possible
if (dataPoints.length > 0 && dataPoints[dataPoints.length – 1].weight > goalWeight) {
var lastDataPoint = dataPoints[dataPoints.length – 1];
if (lastDataPoint.date !== endDate) { // Add end date if not already there
dataPoints.push({ week: totalWeeksAvailable.toFixed(2), weight: goalWeight, date: endDate.toLocaleDateString(undefined, dateOptions) });
}
}
// Build table rows
tableRows = dataPoints.map(function(dp) {
return `
${dp.week.toFixed(1)}
${dp.date}
${(currentWeight – dp.weight).toFixed(2)}
${dp.weight.toFixed(2)}
`;
}).join(");
progressTableBody.innerHTML = tableRows;
// — Chart Update —
if (chartInstance) {
chartInstance.destroy(); // Destroy previous chart instance
}
var ctx = weightLossChartCanvas.getContext('2d');
var chartLabels = dataPoints.map(function(dp) { return dp.date; });
var chartDataSeries1 = dataPoints.map(function(dp) { return dp.weight; }); // Projected Weight
var chartDataSeries2 = dataPoints.map(function(dp) { return currentWeight – (currentWeight – goalWeight) * (dp.week / totalWeeksAvailable); }); // Linear ideal path to goal
// Ensure series lengths match labels length
while(chartDataSeries2.length < chartLabels.length) {
chartDataSeries2.push(null); // Pad with null if needed
}
chartDataSeries2 = chartDataSeries2.slice(0, chartLabels.length);
chartInstance = new Chart(ctx, {
type: 'line',
data: {
labels: chartLabels,
datasets: [{
label: 'Projected Weight',
data: chartDataSeries1,
borderColor: 'var(–primary-color)',
backgroundColor: 'rgba(0, 74, 153, 0.2)',
fill: true,
tension: 0.1
}, {
label: 'Ideal Path to Goal',
data: chartDataSeries2,
borderColor: 'var(–success-color)',
backgroundColor: 'rgba(40, 167, 69, 0.2)',
fill: false, // Don't fill under the ideal path line
borderDash: [5, 5], // Dashed line for ideal path
tension: 0.1
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
y: {
beginAtZero: false,
title: {
display: true,
text: 'Weight (Units)' // Assuming consistent units
}
},
x: {
title: {
display: true,
text: 'Date'
}
}
},
plugins: {
tooltip: {
callbacks: {
label: function(context) {
var label = context.dataset.label || '';
if (label) {
label += ': ';
}
if (context.parsed.y !== null) {
label += context.parsed.y.toFixed(2);
}
return label;
}
}
}
}
}
});
}
function clearErrors() {
document.getElementById('currentWeightError').innerText = '';
document.getElementById('currentWeightError').style.display = 'none';
document.getElementById('goalWeightError').innerText = '';
document.getElementById('goalWeightError').style.display = 'none';
document.getElementById('weeklyLossRateError').innerText = '';
document.getElementById('weeklyLossRateError').style.display = 'none';
document.getElementById('currentDateError').innerText = '';
document.getElementById('currentDateError').style.display = 'none';
document.getElementById('goalDateError').innerText = '';
document.getElementById('goalDateError').style.display = 'none';
}
function resetCalculator() {
document.getElementById('currentWeight').value = '';
document.getElementById('goalWeight').value = '';
document.getElementById('weeklyLossRate').value = '';
document.getElementById('currentDate').value = '';
document.getElementById('goalDate').value = '';
// Reset errors
clearErrors();
// Hide results
resultsDiv.style.display = 'none';
// Clear chart and table
if (chartInstance) {
chartInstance.destroy();
chartInstance = null;
}
progressTableBody.innerHTML = '';
// Optionally set sensible defaults
// For example:
// document.getElementById('currentWeight').value = '75';
// document.getElementById('goalWeight').value = '68';
// document.getElementById('weeklyLossRate').value = '0.5';
// var today = new Date();
// document.getElementById('currentDate').value = today.toISOString().split('T')[0];
// var futureDate = new Date(today);
// futureDate.setDate(today.getDate() + 90); // 90 days in future
// document.getElementById('goalDate').value = futureDate.toISOString().split('T')[0];
// calculateWeightLoss(); // Recalculate with defaults
}
function copyResults() {
var primaryResult = primaryResultElement.innerText;
var totalWeightToLose = totalWeightToLoseElement.innerText;
var estimatedWeeks = estimatedWeeksElement.innerText;
var adjustedWeeklyLoss = actualWeeklyLossElement.innerText;
var assumptions = keyAssumptionsElement.innerText;
var resultText = `— Weight Loss Projection —\n\n`;
resultText += `Status: ${primaryResult}\n`;
resultText += `Total Weight to Lose: ${totalWeightToLose} units\n`;
resultText += `Estimated Weeks Needed (at desired rate): ${estimatedWeeks} weeks\n`;
resultText += `Required Weekly Loss (to meet date): ${adjustedWeeklyLoss} units/week\n\n`;
resultText += `Key Assumptions:\n${assumptions}\n\n`;
resultText += `— Progress Data —\n\n`;
var rows = progressTableBody.querySelectorAll('tr');
rows.forEach(function(row) {
var cells = row.querySelectorAll('td');
if (cells.length === 4) {
resultText += `Week: ${cells[0].innerText}, Date: ${cells[1].innerText}, Weight Lost: ${cells[2].innerText} units, Projected Weight: ${cells[3].innerText} units\n`;
}
});
// Use a temporary textarea to copy to clipboard
var textArea = document.createElement("textarea");
textArea.value = resultText;
textArea.style.position = "fixed";
textArea.style.left = "-9999px";
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 (optional)
console.log(msg);
alert(msg); // Simple alert for feedback
} catch (err) {
console.error('Unable to copy', err);
alert('Failed to copy results. Please copy manually.');
}
document.body.removeChild(textArea);
}
function toggleFaq(element) {
var content = element.nextElementSibling;
var isHidden = content.style.display === 'none' || content.style.display === '';
// Close all other FAQs first
var allFaqs = document.querySelectorAll('.faq-item p');
allFaqs.forEach(function(faqContent) {
if (faqContent !== content) {
faqContent.style.display = 'none';
faqContent.previousElementSibling.style.fontWeight = 'bold';
}
});
// Toggle current FAQ
if (isHidden) {
content.style.display = 'block';
element.style.fontWeight = 'bold';
} else {
content.style.display = 'none';
element.style.fontWeight = 'bold';
}
}
// Initialize chart library if not already loaded (e.g., from an external CDN)
// For this self-contained HTML, we assume Chart.js is available or we'd need to include it.
// In a real WordPress environment, you'd enqueue Chart.js properly.
// Example: Add to the head or before the closing body tag.
// Since we must be self-contained, we'll assume this HTML *would* have Chart.js included.
// Mock Chart.js if not present for testing structure without errors, but actual chart won't render.
// In a production environment, ensure Chart.js is loaded.
if (typeof Chart === 'undefined') {
console.warn("Chart.js not found. Charts will not render. Include Chart.js library.");
window.Chart = function() {
this.destroy = function() {}; // Mock destroy method
};
window.Chart.prototype.destroy = function() {}; // Mock prototype method
}
// Initial setup: set today's date as default for start date
var todayInput = document.getElementById('currentDate');
var today = new Date();
todayInput.value = today.toISOString().split('T')[0];
// Set a default goal date (e.g., 3 months from now) if empty
var goalDateInput = document.getElementById('goalDate');
if (!goalDateInput.value) {
var futureDate = new Date(today);
futureDate.setDate(today.getDate() + 90); // Approx 3 months
goalDateInput.value = futureDate.toISOString().split('T')[0];
}
// Trigger initial calculation if defaults are set meaningfully
// calculateWeightLoss(); // Uncomment if you want defaults to calculate on load