Weight for My Height and Age Calculator

Weight for My Height and Age Calculator – Calculate Your Ideal Weight Range :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –border-color: #dee2e6; –card-background: #ffffff; –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); margin: 0; padding: 0; line-height: 1.6; } .container { max-width: 980px; margin: 20px auto; padding: 0 20px; display: flex; flex-direction: column; align-items: center; } .header { background-color: var(–primary-color); color: white; padding: 20px 0; text-align: center; width: 100%; box-shadow: var(–shadow); } .header h1 { margin: 0; font-size: 2.2em; } .main-content { background-color: var(–card-background); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-top: 20px; width: 100%; box-sizing: border-box; } .calculator-wrapper { background-color: var(–card-background); 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Weight for My Height and Age Calculator

Calculate Your Healthy Weight Range

Male Female Select your gender for more accurate calculations.
Enter your age in whole years.
Centimeters (cm) Feet and Inches (ft'in")
Enter height in centimeters.
Kilograms (kg) Pounds (lbs) Enter your current weight in kilograms or pounds.
Your Calculated Weight Range

BMI:

Ideal Weight Range (kg):

Ideal Weight Range (lbs):

Formula Explanation

This calculator uses standard formulas to estimate a healthy weight range. The primary methods include Body Mass Index (BMI) and adjusted weight formulas that consider age and gender to provide a more personalized range.

BMI Calculation: Weight (kg) / (Height (m))^2

Healthy BMI Range: 18.5 – 24.9

Ideal Weight Estimation: Utilizes formulas like Devine, Robinson, Miller, and Hamwi, adjusted for gender and age. For adults, we focus on a range that typically falls within a healthy BMI, often using an average of these formulas.

Healthy Weight Range vs. Current Weight
Healthy Weight Ranges by Height and Age Group
Age Group Height Range (cm) Healthy Weight Range (kg) Healthy Weight Range (lbs)

Weight for My Height and Age Calculator

Understanding your healthy weight range is a crucial step towards achieving and maintaining overall well-being. The **weight for my height and age calculator** is a valuable tool designed to provide personalized insights based on your specific physical attributes. It goes beyond simple BMI calculations by considering factors like age and gender, offering a more nuanced perspective on what constitutes a healthy weight for you.

What is a Weight for My Height and Age Calculator?

A **weight for my height and age calculator** is a digital tool that helps individuals estimate a healthy weight range based on their biological sex, age, height, and current weight. Unlike basic BMI calculators, these advanced tools often incorporate more sophisticated algorithms that may adjust ideal weight estimations based on age-related physiological changes and typical body composition differences between genders. The goal is to provide a more personalized and comprehensive assessment of weight status, moving beyond a one-size-fits-all approach.

Who should use it:

  • Individuals seeking to understand if their current weight falls within a healthy range for their specific demographics.
  • People aiming to set realistic and healthy weight loss or gain goals.
  • Those interested in a more personalized health assessment than a standard BMI offers.
  • Health professionals using it as an initial screening tool for clients.

Common misconceptions:

  • "It gives an exact ideal weight": The calculator provides a range, not a single magic number. Individual body composition (muscle vs. fat) and frame size play significant roles.
  • "It replaces a doctor's advice": This tool is for informational purposes and does not substitute professional medical diagnosis or treatment plans.
  • "Age and gender are the only other factors": While important, other factors like genetics, activity level, and underlying health conditions also influence healthy weight.

Weight for My Height and Age Calculator Formula and Mathematical Explanation

The calculation of a healthy weight range involves several steps and formulas, often combining established methods to provide a robust estimate. The core components typically include BMI calculation and the use of various established ideal weight formulas, which are then contextualized by age and gender.

Body Mass Index (BMI)

BMI is a widely used screening tool, though it has limitations. It's calculated as:

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

A standard healthy BMI range is generally considered to be between 18.5 and 24.9. The calculator first determines your BMI based on your input weight and height.

Ideal Weight Formulas

Several formulas have been developed over the years to estimate ideal body weight. These often serve as a basis for the weight range provided by the calculator. Common formulas include:

  • Devine Formula:
    • Men: 50 kg + 2.3 kg for each inch over 5 feet
    • Women: 45.5 kg + 2.3 kg for each inch over 5 feet
  • Robinson Formula:
    • Men: 52 kg + 1.9 kg for each inch over 5 feet
    • Women: 53 kg + 1.3 kg for each inch over 5 feet
  • Miller Formula:
    • Men: 56.2 kg + 1.41 kg for each inch over 5 feet
    • Women: 53.1 kg + 1.36 kg for each inch over 5 feet
  • Hamwi Formula:
    • Men: 48 kg + 2.7 kg for each inch over 5 feet
    • Women: 45.5 kg + 2.2 kg for each inch over 5 feet

These formulas are typically applied to adults and provide a starting point. The calculator might average these or use a specific one and then apply a range (e.g., +/- 10%) to account for variations in frame size and muscle mass. For the purpose of a **weight for my height and age calculator**, these adult formulas are often the baseline, with age adjustments being more qualitative (e.g., recognizing that metabolic rates can change) rather than a direct mathematical input in simpler versions.

Age and Gender Adjustments

While exact age-based formulas are less common for adults beyond childhood, the calculator acknowledges that ideal weight can subtly shift. Metabolic rate can decrease with age, and body composition changes. Gender differences are more pronounced, reflected in the different base weights and multipliers in the formulas above. The calculator uses these distinct formulas for males and females.

Variable Explanations

Variable Meaning Unit Typical Range
Gender Biological sex of the individual Categorical (Male/Female) Male, Female
Age Number of years since birth Years 18-80+ (for adult calculators)
Height Vertical distance from base to top of head cm, m, ft'in" 140cm – 200cm (approx.)
Weight Mass of the individual kg, lbs 40kg – 150kg (approx.)
BMI Body Mass Index kg/m² 18.5 – 24.9 (Healthy)
Ideal Weight Range Estimated healthy weight boundaries kg, lbs Varies based on height, age, gender

Practical Examples (Real-World Use Cases)

Example 1: A Young Adult Male

Inputs:

  • Gender: Male
  • Age: 25
  • Height: 180 cm
  • Weight: 75 kg

Calculation:

  • Height in meters: 1.80 m
  • BMI = 75 / (1.80 * 1.80) = 75 / 3.24 ≈ 23.15
  • Using a combination of adult ideal weight formulas (e.g., Devine, Robinson), the estimated ideal weight range for a male of this height is approximately 67 kg to 80 kg (148 lbs to 176 lbs).

Interpretation: With a BMI of 23.15, this individual falls squarely within the healthy BMI range. Their current weight of 75 kg is also within the calculated ideal weight range, suggesting a healthy weight status for their height, age, and gender. This aligns with the goal of maintaining a healthy weight.

Example 2: A Middle-Aged Female

Inputs:

  • Gender: Female
  • Age: 55
  • Height: 165 cm
  • Weight: 68 kg

Calculation:

  • Height in meters: 1.65 m
  • BMI = 68 / (1.65 * 1.65) = 68 / 2.7225 ≈ 24.98
  • Using a combination of adult ideal weight formulas for females, the estimated ideal weight range for a female of this height is approximately 55 kg to 67 kg (121 lbs to 148 lbs).

Interpretation: This individual has a BMI of approximately 24.98, which is at the very upper limit of the healthy range. Her current weight of 68 kg is slightly above the upper end of the calculated ideal weight range (up to 67 kg). While still technically within a healthy BMI, this might suggest that focusing on maintaining current weight or making gradual lifestyle changes to move towards the middle of the range could be beneficial for long-term health. The **weight for my height and age calculator** helps highlight this nuance.

How to Use This Weight for My Height and Age Calculator

Using the **weight for my height and age calculator** is straightforward. Follow these steps to get your personalized healthy weight range:

  1. Select Gender: Choose 'Male' or 'Female' from the dropdown menu. This helps tailor the calculations based on typical physiological differences.
  2. Enter Age: Input your current age in years. While standard adult formulas often treat ages 18+ similarly, some advanced models might apply subtle adjustments.
  3. Input Height: Select your preferred unit (cm or ft'in") and enter your height accurately. Ensure you are standing straight. If selecting ft'in", input both feet and inches.
  4. Enter Current Weight: Choose your preferred unit (kg or lbs) and input your current weight.
  5. Click 'Calculate': Press the calculate button to see your results instantly.

How to read results:

  • Primary Result (Weight Range): This is the core output, showing your estimated healthy weight boundaries in both kg and lbs.
  • BMI: Your calculated Body Mass Index, along with a general classification (e.g., Underweight, Healthy, Overweight, Obese).
  • Intermediate Values: May include breakdowns of different formula estimates or specific health metrics.
  • Chart: Visually represents your current weight against the calculated healthy range.
  • Table: Provides context by showing healthy weight ranges for various height and age brackets.

Decision-making guidance:

  • If your current weight is within the range: Focus on maintaining a healthy lifestyle through balanced nutrition and regular physical activity.
  • If your current weight is below the range: Consult with a healthcare provider to discuss safe and effective ways to gain weight, focusing on muscle mass.
  • If your current weight is above the range: Consider gradual, sustainable lifestyle changes. Focus on a balanced diet and increased physical activity. Consult a doctor or registered dietitian for a personalized plan.

Key Factors That Affect Weight for My Height and Age Calculator Results

While the **weight for my height and age calculator** provides a valuable estimate, several factors can influence your ideal weight and the interpretation of results. It's essential to understand these nuances:

  1. Body Composition: Muscle is denser than fat. A very muscular individual might weigh more but have a lower body fat percentage, appearing "heavier" than their BMI suggests but still being healthy. The calculator doesn't directly measure body fat percentage.
  2. Frame Size: People have different bone structures (small, medium, large frames). The ideal weight formulas offer a range, and where you fall within that might depend on your natural frame.
  3. Age-Related Metabolism: Metabolic rate tends to slow down with age, which can affect weight management. While the calculator might not have complex age-specific metabolic adjustments, it's a factor to consider in real-world application.
  4. Genetics: Your genetic makeup can influence your natural body weight, fat distribution, and metabolism, impacting how well you fit into standard ranges.
  5. Activity Level: A highly active individual may need more weight (muscle) than a sedentary person of the same height and age. The calculator's base formulas don't account for different fitness levels.
  6. Underlying Health Conditions: Certain medical conditions (e.g., thyroid issues, hormonal imbalances, fluid retention) can affect weight independently of diet and exercise.
  7. Pregnancy and Menopause: These life stages involve significant hormonal and physiological changes that alter weight and body composition, making standard calculator results less applicable during these times.

Frequently Asked Questions (FAQ)

Q1: Can the weight for my height and age calculator tell me if I'm overweight or underweight?
A1: Yes, it provides a healthy weight range and your current BMI classification, which helps determine if you are within, below, or above the healthy spectrum for your demographics.
Q2: Are the results from this calculator definitive?
A2: No, the results are estimates. They serve as a helpful guide but do not replace professional medical advice. Factors like body composition and frame size aren't precisely measured.
Q3: How does age affect the ideal weight calculation?
A3: While standard adult formulas are often used, metabolic rate and body composition can change with age. Simpler calculators may not deeply adjust for age, but the range provided remains a good starting point for adults.
Q4: Why is there a range instead of a single ideal weight number?
A4: Because individuals naturally vary in muscle mass, bone density, and body fat percentage. A range acknowledges this natural diversity and identifies a spectrum of healthy weights.
Q5: What is the difference between BMI and the ideal weight range from this calculator?
A5: BMI is a ratio of weight to height squared, providing a general classification. The ideal weight range uses specific formulas that consider height, gender, and sometimes age, to estimate a target weight spectrum.
Q6: Should I be concerned if my weight is just outside the calculated range?
A6: Not necessarily. If you are slightly outside the range but your BMI is still in the healthy category (18.5-24.9), and you feel healthy and energetic, it might not be a concern. However, significant deviation warrants a discussion with a healthcare professional.
Q7: Can this calculator be used for children and teenagers?
A7: This specific calculator is primarily designed for adults. Children and adolescents have different growth patterns, and their healthy weight ranges are best assessed using age-and-gender-specific growth charts (e.g., CDC or WHO growth charts) consulted with a pediatrician.
Q8: How often should I use a weight for my height and age calculator?
A8: You can use it periodically (e.g., every few months or annually) to monitor trends or after significant lifestyle changes. The primary goal is to understand your current status and work towards sustainable health, not to obsess over daily fluctuations.

Related Tools and Internal Resources

var genderSelect = document.getElementById('gender'); var ageInput = document.getElementById('age'); var heightUnitSelect = document.getElementById('heightUnit'); var heightCmInput = document.getElementById('heightCm'); var heightFtInput = document.getElementById('heightFt'); // Will be dynamically added if ft_in is selected var heightInInput = document.getElementById('heightIn'); // Will be dynamically added if ft_in is selected var weightInput = document.getElementById('weight'); var weightUnitSelect = document.getElementById('weightUnit'); var bmiResultSpan = document.getElementById('bmiResult'); var idealWeightKgSpan = document.getElementById('idealWeightKg'); var idealWeightLbsSpan = document.getElementById('idealWeightLbs'); var primaryResultDiv = document.getElementById('primaryResult'); var resultsContainer = document.getElementById('resultsContainer'); var chartContainer = document.getElementById('chartContainer'); var tableBody = document.querySelector('#resultsContainer table tbody'); var canvas = document.getElementById('weightChart'); var ctx; var weightChartInstance = null; var conversionRates = { kg_to_lbs: 2.20462, lbs_to_kg: 0.453592, cm_to_inches: 0.393701, inches_to_cm: 2.54 }; // Dynamic creation of feet/inches inputs heightUnitSelect.addEventListener('change', function() { var selectedUnit = heightUnitSelect.value; var heightInputsDiv = document.getElementById('heightInputs'); heightInputsDiv.innerHTML = "; // Clear existing inputs var helperText = document.createElement('span'); helperText.className = 'helper-text'; if (selectedUnit === 'cm') { heightCmInput = document.createElement('input'); heightCmInput.type = 'number'; heightCmInput.id = 'heightCm'; heightCmInput.placeholder = 'e.g., 175'; heightCmInput.style.display = 'block'; heightCmInput.style.marginTop = '8px'; heightInputsDiv.appendChild(heightCmInput); helperText.textContent = 'Enter height in centimeters.'; heightInputsDiv.appendChild(helperText); // Ensure the global reference is updated if dynamically created document.getElementById('heightCm').addEventListener('input', validateAndCalculate); } else if (selectedUnit === 'ft_in') { var ftDiv = document.createElement('div'); ftDiv.style.display = 'inline-block'; ftDiv.style.marginRight = '5px'; heightFtInput = document.createElement('input'); heightFtInput.type = 'number'; heightFtInput.id = 'heightFt'; heightFtInput.placeholder = "ft (e.g., 5′)"; heightFtInput.style.width = '60px'; ftDiv.appendChild(heightFtInput); ftDiv.appendChild(document.createTextNode(' ft ')); heightInputsDiv.appendChild(ftDiv); var inDiv = document.createElement('div'); inDiv.style.display = 'inline-block'; heightInInput = document.createElement('input'); heightInInput.type = 'number'; heightInInput.id = 'heightIn'; heightInInput.placeholder = 'in (e.g., 9″)'; heightInInput.style.width = '60px'; inDiv.appendChild(heightInInput); inDiv.appendChild(document.createTextNode(' in')); heightInputsDiv.appendChild(inDiv); helperText.textContent = 'Enter height in feet and inches.'; heightInputsDiv.appendChild(helperText); // Add event listeners to dynamically created inputs document.getElementById('heightFt').addEventListener('input', validateAndCalculate); document.getElementById('heightIn').addEventListener('input', validateAndCalculate); } validateAndCalculate(); // Recalculate after unit change }); // Initial setup for height inputs function initializeHeightInputs() { var selectedUnit = heightUnitSelect.value; var heightInputsDiv = document.getElementById('heightInputs'); heightInputsDiv.innerHTML = "; // Clear existing inputs var helperText = document.createElement('span'); helperText.className = 'helper-text'; if (selectedUnit === 'cm') { heightCmInput = document.createElement('input'); heightCmInput.type = 'number'; heightCmInput.id = 'heightCm'; heightCmInput.placeholder = 'e.g., 175'; heightCmInput.style.display = 'block'; heightCmInput.style.marginTop = '8px'; heightInputsDiv.appendChild(heightCmInput); helperText.textContent = 'Enter height in centimeters.'; heightInputsDiv.appendChild(helperText); document.getElementById('heightCm').addEventListener('input', validateAndCalculate); } else { // ft_in var ftDiv = document.createElement('div'); ftDiv.style.display = 'inline-block'; ftDiv.style.marginRight = '5px'; heightFtInput = document.createElement('input'); heightFtInput.type = 'number'; heightFtInput.id = 'heightFt'; heightFtInput.placeholder = "ft (e.g., 5′)"; heightFtInput.style.width = '60px'; ftDiv.appendChild(heightFtInput); ftDiv.appendChild(document.createTextNode(' ft ')); heightInputsDiv.appendChild(ftDiv); var inDiv = document.createElement('div'); inDiv.style.display = 'inline-block'; heightInInput = document.createElement('input'); heightInInput.type = 'number'; heightInInput.id = 'heightIn'; heightInInput.placeholder = 'in (e.g., 9″)'; heightInInput.style.width = '60px'; inDiv.appendChild(heightInInput); inDiv.appendChild(document.createTextNode(' in')); heightInputsDiv.appendChild(inDiv); helperText.textContent = 'Enter height in feet and inches.'; heightInputsDiv.appendChild(helperText); document.getElementById('heightFt').addEventListener('input', validateAndCalculate); document.getElementById('heightIn').addEventListener('input', validateAndCalculate); } } initializeHeightInputs(); // Initialize on load function get and ValidateInputs() { var gender = genderSelect.value; var age = parseFloat(ageInput.value); var heightUnit = heightUnitSelect.value; var height = 0; var weight = parseFloat(weightInput.value); var weightUnit = weightUnitSelect.value; // Reset errors document.getElementById('ageError').textContent = "; document.getElementById('heightError').textContent = "; document.getElementById('weightError').textContent = "; ageInput.classList.remove('error-input'); weightInput.classList.remove('error-input'); if (heightCmInput) heightCmInput.classList.remove('error-input'); if (heightFtInput) heightFtInput.classList.remove('error-input'); if (heightInInput) heightInInput.classList.remove('error-input'); var isValid = true; if (isNaN(age) || age 120) { document.getElementById('ageError').textContent = 'Please enter a valid age between 1 and 120.'; ageInput.classList.add('error-input'); isValid = false; } if (isNaN(weight) || weight <= 0) { document.getElementById('weightError').textContent = 'Please enter a valid weight.'; weightInput.classList.add('error-input'); isValid = false; } if (heightUnit === 'cm') { height = parseFloat(heightCmInput.value); if (isNaN(height) || height 272) { // Approx 8ft 11in max realistic height document.getElementById('heightError').textContent = 'Please enter a valid height in cm (e.g., 150-200).'; heightCmInput.classList.add('error-input'); isValid = false; } } else { // ft_in var feet = parseFloat(heightFtInput.value); var inches = parseFloat(heightInInput.value); if (isNaN(feet) || feet 8) { // Max realistic height in feet document.getElementById('heightError').textContent = 'Please enter valid feet (0-8).'; heightFtInput.classList.add('error-input'); isValid = false; } if (isNaN(inches) || inches = 12) { document.getElementById('heightError').textContent += (document.getElementById('heightError').textContent ? ' ' : ") + 'Please enter valid inches (0-11).'; heightInInput.classList.add('error-input'); isValid = false; } if (isValid) { // Only calculate total inches if feet/inches are individually valid height = (feet * 12) + inches; } else { height = NaN; // Ensure height is NaN if individual parts failed validation } } if (isNaN(height) || height <= 0) { // Catching the case where ft/in combo failed if (heightUnit === 'cm' && !isNaN(height)) {} else { // Avoid duplicate error message for cm document.getElementById('heightError').textContent += (document.getElementById('heightError').textContent ? ' ' : '') + 'Please enter a valid height.'; isValid = false; } } // Convert weight to kg and height to meters for BMI var weightKg = weight; if (weightUnit === 'lbs') { weightKg = weight * conversionRates.lbs_to_kg; } var heightM = height / 100; // If height is in cm if (heightUnit === 'ft_in') { heightM = height * 0.0254; // Convert total inches to meters } // Convert height to cm for table/range calculations if needed var heightCmForTable = height; if (heightUnit === 'ft_in') { heightCmForTable = height * 2.54; // Convert total inches to cm } return { gender: gender, age: age, heightCm: heightCmForTable, // Always in cm for internal use heightM: heightM, // Always in meters for BMI weightKg: weightKg, // Always in kg for internal use weightUnit: weightUnit, // Keep original for display isValid: isValid }; } function calculateBmi(weightKg, heightM) { if (isNaN(weightKg) || isNaN(heightM) || heightM === 0) return NaN; return weightKg / (heightM * heightM); } function getBmiCategory(bmi) { if (isNaN(bmi)) return "N/A"; if (bmi = 18.5 && bmi = 25 && bmi <= 29.9) return "Overweight"; return "Obese"; } function calculateIdealWeightRange(gender, heightCm) { var heightInches = heightCm * conversionRates.cm_to_inches; var idealWeights = []; // Devine Formula var devineBaseM = 50; var devineBaseF = 45.5; var devineMultiplier = 2.3; var devineM = devineBaseM + devineMultiplier * (heightInches – 60); var devineF = devineBaseF + devineMultiplier * (heightInches – 60); idealWeights.push(gender === 'male' ? devineM : devineF); // Robinson Formula var robinsonBaseM = 52; var robinsonBaseF = 53; var robinsonMultiplier = gender === 'male' ? 1.9 : 1.3; // Robinson formula often uses 5'0" (60 inches) as base // Let's adjust for inches over 5ft (60 inches) var inchesOver5Ft = heightInches – 60; if (inchesOver5Ft < 0) inchesOver5Ft = 0; // Ensure not negative if shorter than 5ft var robinsonM = robinsonBaseM + 1.9 * inchesOver5Ft; var robinsonF = robinsonBaseF + 1.3 * inchesOver5Ft; idealWeights.push(gender === 'male' ? robinsonM : robinsonF); // Miller Formula var millerBaseM = 56.2; var millerBaseF = 53.1; var millerMultiplier = gender === 'male' ? 1.41 : 1.36; // Miller formula uses 5'0" (60 inches) as base // Let's adjust for inches over 5ft (60 inches) var inchesOver5FtMiller = heightInches – 60; if (inchesOver5FtMiller < 0) inchesOver5FtMiller = 0; var millerM = millerBaseM + 1.41 * inchesOver5FtMiller; var millerF = millerBaseF + 1.36 * inchesOver5FtMiller; idealWeights.push(gender === 'male' ? millerM : millerF); // Hamwi Formula var hamwiBaseM = 48; var hamwiBaseF = 45.5; var hamwiMultiplier = gender === 'male' ? 2.7 : 2.2; // Hamwi formula uses 5'0" (60 inches) as base // Let's adjust for inches over 5ft (60 inches) var inchesOver5FtHamwi = heightInches – 60; if (inchesOver5FtHamwi 0; }); if (idealWeights.length === 0) return { min: NaN, max: NaN }; var minWeight = Math.min.apply(null, idealWeights); var maxWeight = Math.max.apply(null, idealWeights); // Add a buffer/range, e.g., +/- 10% of the average or simply use min/max directly // For simplicity, we'll use the min/max from the calculated formulas as the range boundaries // A common approach is to use +/- 10% around an average or a specific formula. // Let's use the direct min/max of the applied formulas as the range. // Ensure min is not excessively low and max not excessively high, relative to height // Simple check: min weight should not be less than ~20kg for very short adults, max reasonable ceiling if (minWeight 150) maxWeight = 150; // Arbitrary ceiling return { minKg: minWeight, maxKg: maxWeight }; } function updateChart(currentWeightKg, idealMinKg, idealMaxKg) { if (!ctx) { canvas = document.getElementById('weightChart'); ctx = canvas.getContext('2d'); } if (weightChartInstance) { weightChartInstance.destroy(); // Destroy previous chart instance } var data = { labels: ['Current Weight', 'Healthy Range'], datasets: [{ label: 'Weight (kg)', data: [currentWeightKg, idealMaxKg – idealMinKg], // Represent range as a single value for simplicity, or adjust approach backgroundColor: 'rgba(0, 74, 153, 0.6)', // Primary color borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1, barPercentage: 0.5, // Make bars narrower categoryPercentage: 0.6 // Spacing between categories }, { label: 'Healthy Range', data: [idealMaxKg – idealMinKg], // Represent range as a duration backgroundColor: 'rgba(40, 167, 69, 0.6)', // Success color for range borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1, barPercentage: 0.5, categoryPercentage: 0.6 }] }; // Modified dataset structure for clarity: one bar for current weight, range shown with annotations or two bars var chartData = { labels: ['Weight Comparison (kg)'], datasets: [ { label: 'Current Weight', data: [currentWeightKg], backgroundColor: 'rgba(0, 74, 153, 0.7)', borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1 }, { label: 'Healthy Minimum', data: [idealMinKg], backgroundColor: 'rgba(255, 193, 7, 0.3)', // Warning color, transparent borderColor: 'rgba(255, 193, 7, 0.5)', borderWidth: 0 // No visible bar, just for positioning }, { label: 'Healthy Maximum', data: [idealMaxKg], backgroundColor: 'rgba(255, 193, 7, 0.3)', // Warning color, transparent borderColor: 'rgba(255, 193, 7, 0.5)', borderWidth: 0 // No visible bar, just for positioning } ] }; weightChartInstance = new Chart(ctx, { type: 'bar', data: chartData, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: true, title: { display: true, text: 'Weight (kg)' } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.y !== null) { // For Min/Max labels, we want to show the actual value if (label.includes('Minimum') || label.includes('Maximum')) { label += context.parsed.y.toFixed(1) + ' kg'; } else { // For Current Weight, display normally label += context.parsed.y.toFixed(1) + ' kg'; } } return label; } } }, legend: { display: true, position: 'top' } }, // Custom plugin to draw the range rectangle plugins: [rangePlugin] } }); } // Custom Chart.js plugin to draw the healthy range rectangle var rangePlugin = { id: 'rangePlugin', afterDraw: function(chart) { if (chart.config.data.datasets.length > 0) { var ctx = chart.ctx; var chartArea = chart.chartArea; var datasets = chart.config.data.datasets; var idealMinKg = datasets.find(d => d.label === 'Healthy Minimum')?.data[0]; var idealMaxKg = datasets.find(d => d.label === 'Healthy Maximum')?.data[0]; if (idealMinKg !== undefined && idealMaxKg !== undefined && !isNaN(idealMinKg) && !isNaN(idealMaxKg)) { var yScale = chart.scales['y']; var yMin = yScale.getPixelForValue(idealMinKg); var yMax = yScale.getPixelForValue(idealMaxKg); ctx.fillStyle = 'rgba(255, 193, 7, 0.2)'; // Semi-transparent yellow for range highlight ctx.fillRect(chartArea.left, yMax, chartArea.right – chartArea.left, yMin – yMax); // Draw rectangle } } } }; function populateTable(heightCm) { var tableBody = document.querySelector('#resultsContainer table tbody'); tableBody.innerHTML = "; // Clear existing rows var heights = [150, 160, 170, 180, 190]; // Sample heights for table rows var ages = [20, 30, 40, 50, 60]; // Sample ages for table rows // Generate rows based on height for (var i = 0; i < heights.length; i++) { var h = heights[i]; if (h 210) continue; // Skip unrealistic heights for general table var rangeMale = calculateIdealWeightRange('male', h); var rangeFemale = calculateIdealWeightRange('female', h); var row = tableBody.insertRow(); var cellHeight = row.insertCell(0); cellHeight.textContent = h + ' cm'; var cellMaleWeight = row.insertCell(1); cellMaleWeight.textContent = Math.round(rangeMale.minKg) + ' – ' + Math.round(rangeMale.maxKg) + ' kg (' + Math.round(rangeMale.minKg * conversionRates.kg_to_lbs) + ' – ' + Math.round(rangeMale.maxKg * conversionRates.kg_to_lbs) + ' lbs)'; var cellFemaleWeight = row.insertCell(2); cellFemaleWeight.textContent = Math.round(rangeFemale.minKg) + ' – ' + Math.round(rangeFemale.maxKg) + ' kg (' + Math.round(rangeFemale.minKg * conversionRates.kg_to_lbs) + ' – ' + Math.round(rangeFemale.maxKg * conversionRates.kg_to_lbs) + ' lbs)'; } } function calculate() { var inputs = get and ValidateInputs(); if (!inputs.isValid) { resultsContainer.style.display = 'none'; chartContainer.style.display = 'none'; return; } var gender = inputs.gender; var age = inputs.age; var heightCm = inputs.heightCm; var heightM = inputs.heightM; var weightKg = inputs.weightKg; var weightUnit = inputs.weightUnit; // BMI Calculation var bmi = calculateBmi(weightKg, heightM); var bmiCategory = getBmiCategory(bmi); // Ideal Weight Range Calculation var idealRange = calculateIdealWeightRange(gender, heightCm); var minWeightKg = idealRange.minKg; var maxWeightKg = idealRange.maxKg; var minWeightLbs = minWeightKg * conversionRates.kg_to_lbs; var maxWeightLbs = maxWeightKg * conversionRates.kg_to_lbs; // Update Results Display primaryResultDiv.textContent = Math.round(minWeightKg) + ' – ' + Math.round(maxWeightKg) + ' kg'; bmiResultSpan.textContent = bmi.toFixed(2) + ' (' + bmiCategory + ')'; idealWeightKgSpan.textContent = Math.round(minWeightKg) + ' – ' + Math.round(maxWeightKg) + ' kg'; idealWeightLbsSpan.textContent = Math.round(minWeightLbs) + ' – ' + Math.round(maxWeightLbs) + ' lbs'; resultsContainer.style.display = 'block'; // Update Chart if (weightKg > 0 && !isNaN(minWeightKg) && !isNaN(maxWeightKg)) { updateChart(weightKg, minWeightKg, maxWeightKg); chartContainer.style.display = 'block'; } else { chartContainer.style.display = 'none'; } // Update Table (can be static or dynamically generated based on context) populateTable(heightCm); // Populate with sample data for context } function validateAndCalculate() { calculate(); } function resetCalculator() { genderSelect.value = 'male'; ageInput.value = "; heightUnitSelect.value = 'cm'; initializeHeightInputs(); // Re-initialize to show cm input heightCmInput.value = "; weightInput.value = "; // Clear errors and results document.getElementById('ageError').textContent = "; document.getElementById('heightError').textContent = "; document.getElementById('weightError').textContent = "; ageInput.classList.remove('error-input'); weightInput.classList.remove('error-input'); if (heightCmInput) heightCmInput.classList.remove('error-input'); if (heightFtInput) heightFtInput.classList.remove('error-input'); if (heightInInput) heightInInput.classList.remove('error-input'); bmiResultSpan.textContent = "; idealWeightKgSpan.textContent = "; idealWeightLbsSpan.textContent = "; primaryResultDiv.textContent = "; resultsContainer.style.display = 'none'; chartContainer.style.display = 'none'; if (weightChartInstance) { weightChartInstance.destroy(); weightChartInstance = null; } } function copyResults() { var inputs = get and ValidateInputs(); if (!inputs.isValid) { alert("Please calculate valid results before copying."); return; } var gender = genderSelect.value.charAt(0).toUpperCase() + genderSelect.value.slice(1); var age = ageInput.value; var heightUnit = heightUnitSelect.value; var heightDisplay = "; if (heightUnit === 'cm') { heightDisplay = document.getElementById('heightCm').value + ' cm'; } else { heightDisplay = document.getElementById('heightFt').value + " ft " + document.getElementById('heightIn').value + " in"; } var weight = weightInput.value; var weightUnit = weightUnitSelect.value; var bmi = bmiResultSpan.textContent; var idealWeightKg = idealWeightKgSpan.textContent; var idealWeightLbs = idealWeightLbsSpan.textContent; var primaryResult = primaryResultDiv.textContent; var resultText = "— Weight for My Height and Age Calculator Results —\n\n"; resultText += "Inputs:\n"; resultText += "- Gender: " + gender + "\n"; resultText += "- Age: " + age + " years\n"; resultText += "- Height: " + heightDisplay + "\n"; resultText += "- Current Weight: " + weight + " " + weightUnit + "\n\n"; resultText += "Calculated Results:\n"; resultText += "- Healthy Weight Range: " + primaryResult + "\n"; resultText += "- Ideal Weight (kg): " + idealWeightKg + "\n"; resultText += "- Ideal Weight (lbs): " + idealWeightLbs + "\n"; resultText += "- BMI: " + bmi + "\n\n"; resultText += "Assumptions:\n"; resultText += "- Calculations based on standard adult formulas.\n"; resultText += "- BMI categories are standard classifications.\n"; try { navigator.clipboard.writeText(resultText).then(function() { // Success feedback – change button text temporarily var originalText = "Copy Results"; var copyButton = document.querySelector('.copy-button'); copyButton.textContent = "Copied!"; setTimeout(function() { copyButton.textContent = originalText; }, 2000); }).catch(function(err) { console.error('Failed to copy text: ', err); alert('Failed to copy results. Please copy manually.'); }); } catch (e) { console.error('Clipboard API not available or failed: ', e); alert('Failed to copy results. Your browser may not support this feature. Please copy manually.'); } } // Initial calculation on page load if default values are present (optional) // For this setup, we'll wait for user interaction or explicit calculation // calculate(); // Add event listeners for all relevant inputs after initialization document.addEventListener('DOMContentLoaded', function() { genderSelect.addEventListener('change', validateAndCalculate); ageInput.addEventListener('input', validateAndCalculate); weightInput.addEventListener('input', validateAndCalculate); weightUnitSelect.addEventListener('change', validateAndCalculate); // Initialize height inputs and add listeners initializeHeightInputs(); // Initial calculation to populate table and potentially set defaults calculate(); });

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