Uk Ideal Weight Calculator

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UK Ideal Weight Calculator

Determine your healthy weight range in the UK.

Male Female Select your gender for calculation.
Enter your height in centimetres.
Enter your current weight in kilograms.

Your Ideal Weight Results

Your ideal weight is an estimated healthy range. BMI is a common indicator, but consult a healthcare professional for personalised advice.
BMI:
Category:
Healthy Range:
Formula Used (Simplified):
Ideal weight is often estimated using formulas that consider height and gender, with BMI providing a broader health assessment. For this calculator, we primarily use the BMI range (18.5 – 24.9) to determine your healthy weight.

BMI Calculation: BMI = Weight (kg) / (Height (m))^2
Ideal Weight Range Calculation: Lower Bound (kg) = 18.5 * (Height (m))^2 Upper Bound (kg) = 24.9 * (Height (m))^2

BMI vs. Weight Range

Comparison of current weight, ideal weight range, and BMI categories.
Category BMI Range Weight Range (kg) for m
Underweight < 18.5
Healthy Weight 18.5 – 24.9
Overweight 25.0 – 29.9
Obese (Class I) 30.0 – 34.9

What is the UK Ideal Weight Calculator?

The UK Ideal Weight Calculator is a digital tool designed to help individuals in the United Kingdom estimate a healthy weight range based on their physical characteristics, primarily height and gender. It utilises established health metrics, most notably the Body Mass Index (BMI), to provide a personalised target. This calculator is not a diagnostic tool but rather an educational resource to promote awareness of healthy weight management. Understanding your ideal weight can be a motivating first step towards adopting a healthier lifestyle. It helps to set realistic goals and provides a benchmark for assessing current weight status. Many individuals in the UK use this type of calculator to gauge their progress or to understand the implications of their current weight on their overall health. It's a simple yet powerful way to get a personalised health insight. The primary goal of the uk ideal weight calculator is to offer a clear, data-driven estimate.

Who Should Use It?

Anyone concerned about their current weight or seeking to understand what a healthy weight looks like for their body type should consider using the UK Ideal Weight Calculator. This includes:

  • Individuals looking to lose weight or gain weight healthily.
  • People who want to understand their BMI category and its implications.
  • Those embarking on new fitness or diet regimes who need a target to aim for.
  • Health and fitness professionals who use it as a supplementary tool for client consultations.
  • Anyone curious about their personal health metrics and seeking simple, accessible information.

Common Misconceptions

Several misconceptions surround the concept of ideal weight and BMI calculators. Firstly, it's crucial to understand that BMI is an estimate and doesn't account for body composition (muscle vs. fat). A very muscular individual might have a high BMI but be perfectly healthy. Secondly, "ideal weight" is not a single magic number but a healthy range. Factors like age, sex, frame size, and muscle mass can influence where within that range an individual falls. Lastly, the calculator doesn't consider underlying health conditions. Always consult with a healthcare professional for personalised advice. The uk ideal weight calculator provides a starting point, not a definitive diagnosis.

UK Ideal Weight Calculator Formula and Mathematical Explanation

The calculation behind the UK Ideal Weight Calculator primarily relies on the Body Mass Index (BMI) formula and its associated healthy weight ranges. While various specific formulas exist for estimating ideal weight (like the Devine, Robinson, or Miller formulas), the most universally accepted and widely used method for general population health assessment involves BMI.

BMI Calculation

The core formula for BMI is:

BMI = Weight (kg) / (Height (m))^2

Where:

  • Weight is measured in kilograms (kg).
  • Height is measured in meters (m). If you provide height in centimetres, it must be converted to meters by dividing by 100.

Healthy Weight Range Determination

International health organisations, including the World Health Organisation (WHO) and various UK health bodies, define standard BMI categories. The "healthy weight" range is generally considered to be a BMI between 18.5 and 24.9.

To determine the ideal weight range in kilograms for a given height, we rearrange the BMI formula:

Weight (kg) = BMI * (Height (m))^2

Therefore, the ideal weight range is calculated as:

Lower Ideal Weight (kg) = 18.5 * (Height (m))^2

Upper Ideal Weight (kg) = 24.9 * (Height (m))^2

The gender input influences how some specific ideal weight formulas might be adjusted, but for a BMI-based calculator, the height is the primary determinant of the weight range, with gender often being a secondary consideration for specific targets within that range or for interpretation.

Variable Explanations Table

Variable Meaning Unit Typical Range
Height (H) Individual's height Centimetres (cm) or Meters (m) Adults: 140cm – 200cm (1.4m – 2.0m)
Weight (W) Individual's current weight Kilograms (kg) Varies greatly, but calculator uses it for BMI
Gender Biological sex (Male/Female) Categorical Male, Female
BMI Body Mass Index kg/m² 18.5 – 24.9 (Healthy)
Ideal Weight Lower Bound Minimum healthy weight for height Kilograms (kg) Calculated based on height and BMI 18.5
Ideal Weight Upper Bound Maximum healthy weight for height Kilograms (kg) Calculated based on height and BMI 24.9

The uk ideal weight calculator leverages these calculations to provide actionable insights.

Practical Examples (Real-World Use Cases)

Let's look at a couple of scenarios demonstrating how the UK Ideal Weight Calculator can be used:

Example 1: Sarah, Concerned About Recent Weight Gain

Inputs:

  • Gender: Female
  • Height: 165 cm
  • Current Weight: 75 kg

Calculation Steps:

  1. Convert height to meters: 165 cm / 100 = 1.65 m
  2. Calculate BMI: 75 kg / (1.65 m * 1.65 m) = 75 / 2.7225 ≈ 27.55
  3. Determine BMI category: 27.55 falls into the 'Overweight' category (25.0 – 29.9).
  4. Calculate ideal weight lower bound: 18.5 * (1.65 m)^2 = 18.5 * 2.7225 ≈ 50.37 kg
  5. Calculate ideal weight upper bound: 24.9 * (1.65 m)^2 = 24.9 * 2.7225 ≈ 67.79 kg

Outputs:

  • Current BMI: 27.6
  • Weight Category: Overweight
  • Ideal Weight Range: 50.4 kg – 67.8 kg

Interpretation: Sarah's current weight of 75 kg is above the healthy range for her height. Her BMI indicates she is overweight. The calculator suggests a target weight loss to reach a range between approximately 50.4 kg and 67.8 kg. This provides a clear goal for her to aim for through diet and exercise. Understanding this helps Sarah plan her next steps towards a healthier weight.

Example 2: David, A Muscular Young Man

Inputs:

  • Gender: Male
  • Height: 188 cm
  • Current Weight: 95 kg

Calculation Steps:

  1. Convert height to meters: 188 cm / 100 = 1.88 m
  2. Calculate BMI: 95 kg / (1.88 m * 1.88 m) = 95 / 3.5344 ≈ 26.88
  3. Determine BMI category: 26.88 falls into the 'Overweight' category (25.0 – 29.9).
  4. Calculate ideal weight lower bound: 18.5 * (1.88 m)^2 = 18.5 * 3.5344 ≈ 65.39 kg
  5. Calculate ideal weight upper bound: 24.9 * (1.88 m)^2 = 24.9 * 3.5344 ≈ 88.01 kg

Outputs:

  • Current BMI: 26.9
  • Weight Category: Overweight
  • Ideal Weight Range: 65.4 kg – 88.0 kg

Interpretation: David's BMI of 26.9 classifies him as overweight. However, he notes that he is very muscular due to regular weight training. His current weight of 95 kg is higher than the calculated upper limit of the healthy BMI range (88.0 kg). This highlights a limitation of BMI: it doesn't distinguish between muscle mass and fat mass. While David might be well within a healthy body fat percentage, the calculator flags his weight relative to the standard BMI scale. He should use this information cautiously, perhaps focusing more on body fat percentage and fitness levels rather than solely on the number on the scale or the BMI category. The uk ideal weight calculator serves as a general guideline.

How to Use This UK Ideal Weight Calculator

Using our UK Ideal Weight Calculator is straightforward. Follow these simple steps to get your personalised healthy weight range:

Step-by-Step Instructions

  1. Enter Gender: Select 'Male' or 'Female' from the dropdown menu. This helps tailor the general understanding of weight distribution, although the primary calculation relies on height.
  2. Input Height: Enter your height accurately in centimetres (e.g., 170 for 170cm). Ensure the value is positive and reasonable.
  3. Input Current Weight: Enter your current weight in kilograms (e.g., 65 for 65kg). Again, ensure this is a positive and realistic number.
  4. Click 'Calculate': Once all fields are filled, click the 'Calculate' button. The calculator will process your inputs instantly.
  5. Review Results: Your estimated ideal weight range, current BMI, and weight category will be displayed.
  6. Use the Chart and Table: Visualise where your current weight and ideal range sit relative to standard BMI categories.
  7. Reset or Copy: Use the 'Reset' button to clear the fields and start over. Use 'Copy Results' to save or share your calculated data.

How to Read Results

  • Main Result (Ideal Weight Range): This shows the estimated weight (in kg) that is considered healthy for your height. It's presented as a range (e.g., 60.1 kg – 81.1 kg).
  • BMI Value: Your current Body Mass Index, calculated from your entered weight and height.
  • Weight Category: This classifies your current BMI into standard categories: Underweight, Healthy Weight, Overweight, or Obese.
  • Chart and Table: These provide a visual and tabular comparison of different weight categories against your height and current weight.

Decision-Making Guidance

Use the results as a guide, not a definitive rulebook. If your BMI falls into the 'Healthy Weight' category, maintaining your current weight through balanced diet and exercise is recommended. If you are in the 'Underweight', 'Overweight', or 'Obese' categories, consider consulting with a healthcare professional or a registered dietitian. They can provide personalised advice based on your overall health, medical history, and lifestyle. Remember, muscle weighs more than fat, so if you are very active, your BMI might be higher than ideal due to muscle mass. Focus on how you feel, your energy levels, and overall fitness.

Key Factors That Affect Ideal Weight Results

While the uk ideal weight calculator provides a valuable estimate, several factors can influence your personal ideal weight and the interpretation of the results:

  1. Body Composition: This is perhaps the most significant factor often overlooked by basic BMI calculations. Muscle tissue is denser than fat tissue. Individuals with a high muscle mass (e.g., athletes, bodybuilders) may have a higher weight and BMI than the "ideal" range suggests, yet possess a very low body fat percentage and be exceptionally healthy. Conversely, someone with low muscle mass might fall within the BMI healthy range but have a high body fat percentage, indicating potential health risks.
  2. Age: Metabolic rates tend to slow down with age, and body composition changes naturally. While the BMI formula doesn't explicitly include age, its interpretation can vary. For older adults, maintaining a slightly higher weight within the healthy BMI range might be beneficial for bone health and preventing frailty. Conversely, for children and adolescents, specific BMI-for-age percentiles are used, as their bodies are still developing.
  3. Frame Size: People naturally have different bone structures and skeletal frames (small, medium, large). A person with a large frame might naturally carry more weight due to bone density and size, even if they have a healthy body fat percentage. Standard BMI calculations do not account for frame size, potentially classifying larger-boned individuals as overweight.
  4. Genetics: Our genetic makeup plays a role in how our bodies store fat, distribute weight, and regulate metabolism. Some individuals may be genetically predisposed to being heavier or leaner, irrespective of diet and exercise to some extent. While genetics don't dictate destiny, they are a contributing factor to individual body type.
  5. Sex/Gender: Biological differences between males and females influence body composition. On average, women tend to have a higher percentage of body fat than men to support reproductive functions, while men tend to have more muscle mass. This can affect how ideal weight ranges are interpreted, although standard BMI calculations are often applied universally.
  6. Hormonal Factors & Medical Conditions: Certain hormonal imbalances (e.g., thyroid issues, PCOS) or medical conditions can significantly impact weight, fluid retention, and metabolism. These factors require medical management and may mean that a standard "ideal weight" is not achievable or even appropriate for the individual. Always discuss weight management with a doctor if medical conditions are present.
  7. Lifestyle and Activity Level: A sedentary lifestyle contributes to lower muscle mass and higher body fat, influencing whether one is within a healthy weight range. Conversely, regular physical activity, especially resistance training, increases muscle mass, potentially raising BMI but improving overall health markers.

The uk ideal weight calculator is a useful tool, but it's essential to consider these nuances for a comprehensive understanding of your health.

Frequently Asked Questions (FAQ)

  • Q1: Is BMI the only way to determine a healthy weight?

    No, BMI is a widely used screening tool but has limitations. It doesn't distinguish between fat and muscle mass. Other factors like body fat percentage, waist circumference, and overall fitness levels are also important indicators of health.

  • Q2: My BMI says I'm overweight, but I exercise regularly. What should I do?

    This is common for individuals with significant muscle mass. If you are active and feel healthy, focus on body fat percentage and how your clothes fit rather than just the BMI number. Consult a fitness professional or doctor for a more detailed assessment.

  • Q3: How accurate is the "ideal weight range" from the calculator?

    The range is based on standard BMI guidelines (18.5-24.9). It provides a general estimate for the population. Your personal ideal weight might vary based on genetics, frame size, and body composition.

  • Q4: Does gender significantly affect the ideal weight calculation?

    Standard BMI-based calculators use height as the primary factor for the weight range. While general physiological differences exist between genders regarding muscle mass and fat distribution, the core healthy BMI range is applied broadly. Some specific formulas might adjust slightly for gender, but this calculator primarily uses height.

  • Q5: What if my current weight is outside the ideal range?

    If your weight is outside the healthy BMI range, it's advisable to consult a healthcare professional. They can help you understand the potential health implications and develop a safe and effective plan for weight management, whether it involves weight loss or gain.

  • Q6: Can I use this calculator for children?

    No, this calculator is designed for adults. BMI calculations and interpretation for children and adolescents are different and use specific growth charts based on age and sex. Please consult a pediatrician for child weight assessment.

  • Q7: How often should I use an ideal weight calculator?

    You don't need to use it frequently. Use it when you're curious about your general weight status or setting health goals. Focus more on consistent healthy habits rather than obsessing over the numbers. Regular health check-ups with a doctor are more crucial.

  • Q8: What are the risks of being underweight or overweight?

    Being underweight can lead to nutrient deficiencies, weakened immunity, and osteoporosis. Being overweight or obese increases the risk of type 2 diabetes, heart disease, high blood pressure, certain cancers, and joint problems. Maintaining a healthy weight range is crucial for long-term health.

  • Q9: Should I aim for the lower or upper end of the ideal weight range?

    Aiming for the middle of the healthy BMI range is generally recommended. However, individual factors like muscle mass and fitness levels can influence whether being towards the lower or upper end is more appropriate for you. Consult a health professional for personalised advice.

Related Tools and Internal Resources

Disclaimer: This calculator and the accompanying information are for educational purposes only and do not constitute medical advice. Always consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.

function calculateIdealWeight() { var heightCmInput = document.getElementById('heightCm'); var weightKgInput = document.getElementById('weightKg'); var genderSelect = document.getElementById('gender'); var heightCmError = document.getElementById('heightCmError'); var weightKgError = document.getElementById('weightKgError'); var resultsSection = document.getElementById('resultsSection'); var bmiValueSpan = document.getElementById('bmiValue').querySelector('span'); var weightCategorySpan = document.getElementById('weightCategory').querySelector('span'); var healthyRangeSpan = document.getElementById('healthyRange').querySelector('span'); var idealWeightResultDiv = document.getElementById('idealWeightResult'); var chartHeightKgSpan = document.getElementById('chartHeightKg'); var bmiTableBody = document.getElementById('bmiTableBody'); // Clear previous errors heightCmError.textContent = "; weightKgError.textContent = "; var heightCm = parseFloat(heightCmInput.value); var weightKg = parseFloat(weightKgInput.value); var gender = genderSelect.value; // — Validation — var isValid = true; if (isNaN(heightCm) || heightCm 300) { // Unrealistic height heightCmError.textContent = 'Height seems too high. Please check.'; isValid = false; } if (isNaN(weightKg) || weightKg 1000) { // Unrealistic weight weightKgError.textContent = 'Weight seems too high. Please check.'; isValid = false; } if (!isValid) { resultsSection.style.display = 'none'; return; } // — Calculations — var heightM = heightCm / 100; var bmi = weightKg / (heightM * heightM); var bmiRounded = bmi.toFixed(1); var idealWeightLowerKg = (18.5 * (heightM * heightM)).toFixed(1); var idealWeightUpperKg = (24.9 * (heightM * heightM)).toFixed(1); var weightCategory = "; var idealWeightResultText = "; if (bmi = 18.5 && bmi = 25 && bmi <= 29.9) { weightCategory = 'Overweight'; } else { weightCategory = 'Obese'; } // Primary Result Display if (weightCategory === 'Healthy Weight') { idealWeightResultText = idealWeightLowerKg + ' – ' + idealWeightUpperKg + ' kg'; idealWeightResultDiv.style.color = 'var(–success-color)'; } else { idealWeightResultText = idealWeightLowerKg + ' – ' + idealWeightUpperKg + ' kg'; idealWeightResultDiv.style.color = '#e0a000'; // Orange for ranges outside healthy } // Update Results Section bmiValueSpan.textContent = bmiRounded; weightCategorySpan.textContent = weightCategory; healthyRangeSpan.textContent = idealWeightLowerKg + ' – ' + idealWeightUpperKg + ' kg'; idealWeightResultDiv.textContent = idealWeightResultText; chartHeightKgSpan.textContent = heightM.toFixed(2); // Display height in meters for table header resultsSection.style.display = 'block'; // — Update Table Data — var underweightRange = (18.4 * (heightM * heightM)).toFixed(1) + ' kg'; var overweightRange = (29.9 * (heightM * heightM)).toFixed(1) + ' kg'; var obeseRange = (35 * (heightM * heightM)).toFixed(1) + ' kg'; // Using BMI 35 as a reference for upper end of obese category // Ensure the table body is updated correctly if (bmiTableBody) { bmiTableBody.innerHTML = ` Underweight < 18.5 < ${underweightRange} Healthy Weight 18.5 – 24.9 ${idealWeightLowerKg} – ${idealWeightUpperKg} kg Overweight 25.0 – 29.9 ${(25.0 * (heightM * heightM)).toFixed(1)} – ${overweightRange} Obese (Class I+) ≥ 30.0 ≥ ${(30.0 * (heightM * heightM)).toFixed(1)} kg `; } // — Update Chart — updateChart(heightM, bmi, weightKg, parseFloat(idealWeightLowerKg), parseFloat(idealWeightUpperKg)); } function updateChart(heightM, currentBmi, currentWeightKg, idealLowerKg, idealUpperKg) { var ctx = document.getElementById('weightChart').getContext('2d'); // Clear previous chart if it exists if (window.myWeightChart) { window.myWeightChart.destroy(); } // Define weight ranges for chart axes based on typical BMI categories var weightRangeMax = Math.max(currentWeightKg, idealUpperKg, 120) * 1.1; // Ensure chart can accommodate current weight and upper range var weightRangeMin = 0; // Start from 0 for clarity var bmiRanges = { underweight: { maxKg: 18.5 * heightM * heightM, color: '#4e79a7' }, // Blue healthy: { minKg: 18.5 * heightM * heightM, maxKg: 24.9 * heightM * heightM, color: '#50c878' }, // Green overweight: { minKg: 25.0 * heightM * heightM, maxKg: 29.9 * heightM * heightM, color: '#f28e2b' }, // Orange obese: { minKg: 30.0 * heightM * heightM, color: '#e15759' } // Red }; var chartData = { labels: ['Weight (kg)'], datasets: [ { label: 'Current Weight', data: [currentWeightKg], backgroundColor: 'rgba(255, 99, 132, 0.6)', // Reddish for current borderColor: 'rgba(255, 99, 132, 1)', borderWidth: 1, type: 'bar', // Use bar for single point order: 2 }, { label: 'Ideal Weight Range', data: [[idealLowerKg, idealUpperKg]], // Represent range as a bar backgroundColor: 'rgba(40, 167, 69, 0.5)', // Greenish for ideal range borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1, type: 'bar', order: 1 }, // Add bars for BMI categories for visual context { label: 'Underweight Range', data: [[weightRangeMin, bmiRanges.underweight.maxKg]], backgroundColor: bmiRanges.underweight.color, borderColor: bmiRanges.underweight.color, borderWidth: 1, type: 'bar', order: 0 }, { label: 'Overweight Range', data: [[bmiRanges.overweight.minKg, bmiRanges.overweight.maxKg]], backgroundColor: bmiRanges.overweight.color, borderColor: bmiRanges.overweight.color, borderWidth: 1, type: 'bar', order: 0 }, { label: 'Obese Range', data: [[bmiRanges.obese.minKg, weightRangeMax]], // Extends to max backgroundColor: bmiRanges.obese.color, borderColor: bmiRanges.obese.color, borderWidth: 1, type: 'bar', order: 0 } ] }; window.myWeightChart = new Chart(ctx, { data: chartData, options: { indexAxis: 'y', // Horizontal bar chart scales: { x: { beginAtZero: true, max: weightRangeMax, title: { display: true, text: 'Weight (kg)' } }, y: { display: false // Hide y-axis labels for the single category } }, plugins: { title: { display: true, text: 'Weight Comparison', font: { size: 16 } }, legend: { position: 'top', labels: { // Filter out duplicate labels if necessary, or ensure unique ones filter: function(legendItem, chartData) { // Ensure unique labels for legend, e.g., only show one 'Range' if multiple exist if (legendItem.datasetIndex === 0 || legendItem.datasetIndex === 1) return true; // Show current weight and ideal range // Show BMI category bars only once if (legendItem.datasetIndex === 2) return true; // Underweight if (legendItem.datasetIndex === 3) return true; // Overweight if (legendItem.datasetIndex === 4) return true; // Obese return false; } } }, tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.dataset.type === 'bar' && context.dataset.data[context.dataIndex].length === 2) { // It's a range label += context.raw[0].toFixed(1) + ' – ' + context.raw[1].toFixed(1) + ' kg'; } else { // It's a single value label += context.parsed.x.toFixed(1) + ' kg'; } return label; } } } }, responsive: true, maintainAspectRatio: false, animation: { duration: 500, onComplete: function() { var chartInstance = this.chart; var ctx = chartInstance.ctx; var chartArea = chartInstance.chartArea; // Add text labels inside bars if needed (advanced, can be complex) } } } }); } function resetCalculator() { document.getElementById('gender').value = 'male'; document.getElementById('heightCm').value = "; document.getElementById('weightKg').value = "; document.getElementById('heightCmError').textContent = "; document.getElementById('weightKgError').textContent = "; document.getElementById('resultsSection').style.display = 'none'; if (window.myWeightChart) { window.myWeightChart.destroy(); // Re-init canvas with placeholder or blank state var canvas = document.getElementById('weightChart'); var ctx = canvas.getContext('2d'); ctx.clearRect(0, 0, canvas.width, canvas.height); // Optionally draw a placeholder or message } } function copyResults() { var idealWeight = document.getElementById('idealWeightResult').textContent; var bmi = document.getElementById('bmiValue').querySelector('span').textContent; var category = document.getElementById('weightCategory').querySelector('span').textContent; var range = document.getElementById('healthyRange').querySelector('span').textContent; var heightM = parseFloat(document.getElementById('heightCm').value) / 100; var heightFormatted = heightM > 0 ? heightM.toFixed(2) + 'm' : '–'; var assumptions = "Assumptions:\n"; assumptions += "- Height: " + (heightFormatted === '–' ? 'N/A' : heightFormatted) + "\n"; assumptions += "- Gender: " + document.getElementById('gender').value.charAt(0).toUpperCase() + document.getElementById('gender').value.slice(1) + "\n"; assumptions += "- Based on BMI range: 18.5 – 24.9\n"; var copyText = "— UK Ideal Weight Calculator Results —\n\n"; copyText += "Ideal Weight Range: " + idealWeight + "\n"; copyText += "Current BMI: " + bmi + "\n"; copyText += "Weight Category: " + category + "\n"; copyText += "Healthy Range for your Height: " + range + "\n\n"; copyText += assumptions; navigator.clipboard.writeText(copyText).then(function() { // Optionally provide user feedback like a temporary message alert('Results copied to clipboard!'); }).catch(function(err) { console.error('Failed to copy: ', err); // Provide error feedback if copy fails alert('Failed to copy results. Please copy manually.'); }); } // Initial setup for chart canvas if needed (e.g., setting dimensions) var canvas = document.getElementById('weightChart'); canvas.width = 600; // Example width canvas.height = 300; // Example height // Load Chart.js library dynamically if not present if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js'; script.onload = function() { // Initial calculation on load if inputs are pre-filled, or just prepare for calculation // calculateIdealWeight(); // Uncomment if you want to auto-calculate on load with default values }; document.head.appendChild(script); } else { // If Chart.js is already loaded, ensure chart is ready for potential initial calculation // calculateIdealWeight(); // Uncomment if you want to auto-calculate on load with default values } // Ensure reset works correctly with chart destruction var originalReset = resetCalculator; resetCalculator = function() { originalReset(); // Additional canvas clearing if needed var canvas = document.getElementById('weightChart'); var ctx = canvas.getContext('2d'); ctx.clearRect(0, 0, canvas.width, canvas.height); }

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