Age Weight Calculator Child

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Child Age Weight Calculator

Estimate healthy weight ranges for children based on age using growth percentile data.

Enter Child's Information

Enter age from birth (0 months) up to 240 months (20 years).
Enter current weight in kilograms.

Your Child's Weight Metrics

Estimated Healthy Weight Range (5th-95th Percentile):
Current Percentile Rank:
Growth Status:
How it works: This calculator compares your child's weight-for-age against standard growth charts, typically based on World Health Organization (WHO) or CDC data. It determines where your child's weight falls on the growth curve (percentile rank) and provides an estimated healthy range for their age. A percentile indicates that a child's weight is above that of X% of children of the same age and sex.

Child Weight Percentile Chart

Visualizing your child's weight against standard growth percentiles.

Growth Data Table (Example for 24 Months)

Percentile Weight (kg)

Sample weights for a 24-month-old child based on different percentiles.

Understanding Child Weight and Growth Percentiles

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A child age weight calculator is a valuable tool designed to help parents, caregivers, and healthcare professionals estimate whether a child's weight is within a healthy range for their specific age. It typically uses data from established growth charts, such as those provided by the World Health Organization (WHO) or the Centers for Disease Control and Prevention (CDC), to compare a child's measurements against a statistical norm. The primary output is usually a percentile rank, which indicates how a child's weight compares to other children of the same age and sex.

Who should use it:

  • Parents and guardians monitoring their child's growth and development.
  • Pediatricians and healthcare providers for quick assessments and discussions.
  • Childcare providers who need to understand general growth patterns.
  • Anyone seeking to understand typical weight ranges for children at different ages.

Common misconceptions:

  • Misconception: A specific percentile (e.g., 50th) is the "ideal" weight for every child. Reality: The 50th percentile represents the median, meaning half of children are heavier and half are lighter. A range of percentiles (often 5th to 95th) is considered healthy.
  • Misconception: Falling outside the 5th-95th percentile automatically means a child is unhealthy. Reality: While it warrants medical attention, a consistent percentile is often more important than the specific number. A child consistently at the 98th percentile might be perfectly healthy, just larger than average.
  • Misconception: The calculator provides a diagnosis. Reality: It is an estimation tool. Only a healthcare professional can diagnose growth issues.

{primary_keyword} Formula and Mathematical Explanation

The calculation behind a child age weight calculator isn't a single complex formula in the traditional sense, but rather a lookup and interpolation process based on established growth charts. These charts are derived from extensive statistical data collected from large populations of children.

Steps involved:

  1. Data Source: The calculator references a pre-defined dataset of weights corresponding to specific ages and percentiles (e.g., WHO or CDC growth charts).
  2. Age Grouping: The child's age in months is used to find the relevant data points on the growth chart.
  3. Weight Interpolation: If the child's exact age isn't listed, the calculator interpolates between the nearest data points.
  4. Percentile Calculation: The child's actual weight (in kg) is then compared to the weights listed for their age at different percentiles. The calculator determines which percentile the child's weight falls closest to.
  5. Healthy Range Determination: The calculator identifies the weights corresponding to the 5th and 95th percentiles for the child's age. This range is considered the typical healthy weight spectrum.
  6. Growth Status: Based on the calculated percentile rank and the healthy range, a status is assigned (e.g., Healthy Weight, Underweight, Overweight, Obese). These classifications often follow standard definitions provided by health organizations.

Variables Explained:

Variable Meaning Unit Typical Range
Child's Age The age of the child since birth. Months 0 – 240 months (0-20 years)
Child's Weight The measured weight of the child. Kilograms (kg) 0.5 kg+ (newborns)
Percentile Rank Indicates the child's weight relative to peers of the same age and sex. E.g., 75th percentile means the child weighs more than 75% of peers. % 0% – 100%
Healthy Weight Range The weight range generally considered normal or healthy for the child's age, typically defined by the 5th and 95th percentiles. Kilograms (kg) Varies significantly by age
Growth Status Classification based on percentile rank (e.g., Underweight, Healthy Weight, Overweight, Obese). Categorical Underweight, Healthy Weight, Overweight, Obese

Practical Examples (Real-World Use Cases)

Let's illustrate with practical scenarios using the child age weight calculator:

Example 1: Monitoring a Toddler's Growth

Scenario: Sarah is concerned because her 30-month-old son, Leo, seems smaller than some of his friends. She decides to use the calculator.

Inputs:

  • Child's Age: 30 months
  • Child's Weight: 13.5 kg

Calculator Output:

  • Main Result: Current Percentile Rank: 60th
  • Estimated Healthy Weight Range (5th-95th Percentile): 11.0 kg – 16.5 kg
  • Growth Status: Healthy Weight

Interpretation: The calculator shows that Leo's weight of 13.5 kg falls within the healthy range for a 30-month-old. His 60th percentile rank indicates he is heavier than 60% of boys his age, which is well within the normal spectrum. Sarah can be reassured that Leo is growing appropriately.

Example 2: Assessing a Preschooler's Weight

Scenario: Mark and Jane want to check if their 5-year-old daughter, Emily, is at a healthy weight. Emily is 60 months old and weighs 21 kg.

Inputs:

  • Child's Age: 60 months
  • Child's Weight: 21 kg

Calculator Output:

  • Main Result: Current Percentile Rank: 92nd
  • Estimated Healthy Weight Range (5th-95th Percentile): 15.5 kg – 20.5 kg
  • Growth Status: Overweight

Interpretation: Emily's weight of 21 kg is above the 95th percentile for her age, placing her in the 'Overweight' category according to the calculator's interpretation of standard growth charts. While this is not a diagnosis, it indicates that her weight is higher than typical for her age and sex, and her parents should discuss this with her pediatrician to explore dietary habits, physical activity, and potential underlying causes.

How to Use This Child Age Weight Calculator

Using our child age weight calculator is straightforward. Follow these simple steps to get an estimate of your child's growth percentile:

  1. Input Child's Age: Enter your child's exact age in months into the "Child's Age (in Months)" field. For example, a 2-year-old is 24 months old.
  2. Input Child's Weight: Enter your child's current weight in kilograms (kg) into the "Child's Weight (in Kilograms)" field. Ensure you are using the correct unit.
  3. Click Calculate: Press the "Calculate" button.

How to read results:

  • Main Result (Current Percentile Rank): This number shows where your child's weight ranks compared to other children of the same age and sex. A 50th percentile means they are at the median; a 90th means they are heavier than 90% of peers.
  • Estimated Healthy Weight Range: This indicates the typical weight range considered healthy, usually between the 5th and 95th percentiles.
  • Growth Status: This provides a general classification (Underweight, Healthy Weight, Overweight) based on the calculated percentile.
  • Chart: The dynamic chart visually represents your child's weight percentile against the standard growth curve.
  • Data Table: The table provides sample weights for reference at different percentiles for the specified age.

Decision-making guidance:

  • If your child falls within the 5th to 95th percentile range and has a stable growth pattern over time, it's generally a good sign.
  • If your child falls below the 5th percentile or shows a downward trend in percentiles, consult your pediatrician about potential underweight concerns.
  • If your child falls above the 95th percentile or shows an upward trend, discuss potential overweight or obesity concerns with your pediatrician.
  • Remember, a single measurement is less important than the overall growth trend. Consistent tracking is key. Always consult a healthcare professional for personalized advice.

Key Factors That Affect Child Weight Results

While the child age weight calculator provides a standardized comparison, several factors influence a child's weight and growth trajectory. Understanding these can provide context to the results:

  1. Genetics: Just like adults, children inherit genetic predispositions that influence their body size, build, and metabolism. Some children are naturally larger or leaner than others, even within the same percentile range.
  2. Nutrition: Adequate intake of a balanced diet is crucial for healthy growth. Deficiencies in essential nutrients can lead to underweight, while excessive intake of high-calorie, low-nutrient foods can contribute to overweight.
  3. Physical Activity Levels: Regular physical activity helps children maintain a healthy weight by burning calories and building muscle. Sedentary lifestyles can contribute to weight gain.
  4. Health Conditions: Certain medical conditions, such as thyroid issues, hormonal imbalances, digestive disorders (like celiac disease), or chronic illnesses, can significantly impact a child's weight and growth.
  5. Medications: Some medications can cause weight gain or loss as a side effect, potentially affecting a child's position on the growth charts.
  6. Sleep Patterns: Inadequate or poor-quality sleep has been linked to hormonal changes that can affect appetite and metabolism, potentially influencing weight gain.
  7. Socioeconomic Factors: Access to nutritious food, safe environments for physical activity, and healthcare can be influenced by socioeconomic status, indirectly affecting growth outcomes.
  8. Sex: Growth charts often differentiate between boys and girls, as there are typical differences in growth patterns and body composition between sexes, especially during puberty.

Frequently Asked Questions (FAQ)

1. Is this calculator a substitute for a doctor's visit?

No. This calculator provides an estimate based on standard growth charts. It is a tool for informational purposes and should not replace professional medical advice, diagnosis, or treatment from a qualified healthcare provider.

2. Why do growth charts differ between WHO and CDC?

The WHO growth charts are generally used for infants and children from birth to 2 years old, based on breastfed children as the norm. The CDC growth charts are often used for children aged 2 years and older in the United States, reflecting a broader population.

3. How often should I use a child age weight calculator?

It's advisable to use it periodically, perhaps when you notice significant changes in your child's appetite or activity, or during routine well-child checkups. Your pediatrician will track growth consistently.

4. What if my child's age is not exactly represented on the chart?

Most calculators and growth chart tools use interpolation methods to estimate values between the data points provided in the official charts.

5. Does the calculator consider height?

This specific calculator focuses on weight-for-age. More comprehensive assessments, like BMI-for-age, also consider height, which provides a fuller picture of a child's weight status relative to their body composition.

6. My child is consistently above the 95th percentile. What should I do?

This warrants a discussion with your pediatrician. They can conduct a thorough evaluation, considering family history, diet, activity levels, and other health factors to determine the best course of action.

7. My child is consistently below the 5th percentile. What does this mean?

Similarly, a consistently low percentile should be discussed with a healthcare provider. They can investigate potential reasons, such as nutritional issues, underlying medical conditions, or other growth concerns.

8. Is it normal for a child's percentile to fluctuate?

Some minor fluctuations are normal, especially during growth spurts or periods of illness. However, significant jumps or drops in percentile, or consistently crossing major percentile lines, are usually worth discussing with a doctor.

// Data for WHO Growth Charts (example: for boys, 2-20 years, weight-for-age in kg) // This is a simplified representation. Real charts have many more data points. // Format: { ageInMonths: { percentile5: weight, percentile50: weight, percentile95: weight } } var growthData = { 0: { p5: 2.5, p50: 3.5, p95: 4.5 }, // Newborn 3: { p5: 4.5, p50: 6.0, p95: 8.0 }, 6: { p5: 6.0, p50: 8.0, p95: 10.5 }, 12: { p5: 8.0, p50: 10.5, p95: 13.5 }, 18: { p5: 9.5, p50: 12.5, p95: 16.0 }, 24: { p5: 10.5, p50: 14.0, p95: 18.0 }, // 2 years 30: { p5: 11.5, p50: 15.0, p95: 19.5 }, 36: { p5: 12.0, p50: 16.0, p95: 21.0 }, // 3 years 48: { p5: 13.5, p50: 18.0, p95: 24.0 }, // 4 years 60: { p5: 15.0, p50: 20.0, p95: 27.0 }, // 5 years 72: { p5: 17.0, p50: 22.5, p95: 30.5 }, // 6 years 84: { p5: 19.0, p50: 25.0, p95: 34.0 }, // 7 years 96: { p5: 21.5, p50: 28.0, p95: 38.0 }, // 8 years 108: { p5: 24.0, p50: 31.0, p95: 42.0 }, // 9 years 120: { p5: 26.5, p50: 34.0, p95: 46.0 }, // 10 years 132: { p5: 29.5, p50: 37.5, p95: 50.5 }, // 11 years 144: { p5: 32.5, p50: 41.0, p95: 55.0 }, // 12 years 156: { p5: 35.5, p50: 44.5, p95: 59.5 }, // 13 years 168: { p5: 38.5, p50: 48.0, p95: 64.0 }, // 14 years 180: { p5: 41.0, p50: 51.5, p95: 68.0 }, // 15 years 192: { p5: 43.0, p50: 54.5, p95: 71.5 }, // 16 years 204: { p5: 45.0, p50: 57.0, p95: 74.5 }, // 17 years 216: { p5: 46.5, p50: 59.0, p95: 77.0 }, // 18 years 240: { p5: 50.0, p50: 63.0, p95: 82.0 } // 20 years }; // Simplified data for chart rendering (can be expanded) var chartData = [ { ageMonths: 0, p5: 2.5, p50: 3.5, p95: 4.5 }, { ageMonths: 6, p5: 6.0, p50: 8.0, p95: 10.5 }, { ageMonths: 12, p5: 8.0, p50: 10.5, p95: 13.5 }, { ageMonths: 24, p5: 10.5, p50: 14.0, p95: 18.0 }, { ageMonths: 36, p5: 12.0, p50: 16.0, p95: 21.0 }, { ageMonths: 60, p5: 15.0, p50: 20.0, p95: 27.0 }, { ageMonths: 96, p5: 21.5, p50: 28.0, p95: 38.0 }, { ageMonths: 144, p5: 32.5, p50: 41.0, p95: 55.0 }, { ageMonths: 240, p5: 50.0, p50: 63.0, p95: 82.0 } ]; var myChart = null; // Global variable for the chart instance function getWeightForAge(ageMonths, percentile) { var ages = Object.keys(growthData).map(Number).sort(function(a, b) { return a – b; }); var dataPoints = ages.map(function(age) { return { age: age, p: growthData[age][percentile] }; }); if (ageMonths = dataPoints[dataPoints.length – 1].age) { return dataPoints[dataPoints.length – 1].p; } for (var i = 0; i = dataPoints[i].age && ageMonths <= dataPoints[i + 1].age) { var age1 = dataPoints[i].age; var age2 = dataPoints[i + 1].age; var weight1 = dataPoints[i].p; var weight2 = dataPoints[i + 1].p; // Linear interpolation return weight1 + (weight2 – weight1) * (ageMonths – age1) / (age2 – age1); } } return null; // Should not happen with sorted ages } function getPercentileRank(ageMonths, weightKg) { var ages = Object.keys(growthData).map(Number).sort(function(a, b) { return a – b; }); // Find the two age points surrounding the child's age var lowerAge = ages[0]; var upperAge = ages[ages.length – 1]; for (var i = 0; i < ages.length; i++) { if (ages[i] = ageMonths) { upperAge = ages[i]; break; } } if (ageMonths upperAge) lowerAge = upperAge; // Get weights for 5th, 50th, and 95th percentiles at these ages var lowerP5 = growthData[lowerAge].p5; var lowerP50 = growthData[lowerAge].p50; var lowerP95 = growthData[lowerAge].p95; var upperP5 = growthData[upperAge].p5; var upperP50 = growthData[upperAge].p50; var upperP95 = growthData[upperAge].p95; // Interpolate weights for the child's specific age var interpolatedP5, interpolatedP50, interpolatedP95; if (lowerAge === upperAge) { interpolatedP5 = lowerP5; interpolatedP50 = lowerP50; interpolatedP95 = lowerP95; } else { var factor = (ageMonths – lowerAge) / (upperAge – lowerAge); interpolatedP5 = lowerP5 + (upperP5 – lowerP5) * factor; interpolatedP50 = lowerP50 + (upperP50 – lowerP50) * factor; interpolatedP95 = lowerP95 + (upperP95 – lowerP95) * factor; } // Now, find the percentile rank for the child's weight if (weightKg = interpolatedP95) { return 95; // Above 95th percentile } // Simple linear interpolation for percentile rank between p5 and p95 // This is an approximation. More precise methods exist. var rangeP5_P95 = interpolatedP95 – interpolatedP5; var valueFromP5 = weightKg – interpolatedP5; var percentile = 5 + (valueFromP5 / rangeP5_P95) * 90; // 90 = 95 – 5 return Math.round(percentile); } function getGrowthStatus(percentile) { if (percentile = 5 && percentile 95) { return "Overweight"; } return "N/A"; } function updateGrowthTable(ageMonths) { var tableBody = document.getElementById('growthTableBody'); tableBody.innerHTML = "; // Clear previous content var ages = Object.keys(growthData).map(Number).sort(function(a, b) { return a – b; }); var targetAge = ageMonths; // Find the closest age in our data or interpolate if needed var relevantAges = ages.filter(function(age) { return age 0 ? relevantAges[0] : ages[0]; var upperAge = ages[ages.length – 1]; // Default to last known age if targetAge is very large // Find the next age point if targetAge is between two known points for(var i = 0; i targetAge){ upperAge = ages[i]; break; } } if (targetAge upperAge) lowerAge = upperAge; var p5Weight, p50Weight, p95Weight; if (lowerAge === upperAge) { p5Weight = growthData[lowerAge].p5; p50Weight = growthData[lowerAge].p50; p95Weight = growthData[lowerAge].p95; } else { var factor = (targetAge – lowerAge) / (upperAge – lowerAge); p5Weight = growthData[lowerAge].p5 + (growthData[upperAge].p5 – growthData[lowerAge].p5) * factor; p50Weight = growthData[lowerAge].p50 + (growthData[upperAge].p50 – growthData[lowerAge].p50) * factor; p95Weight = growthData[lowerAge].p95 + (growthData[upperAge].p95 – growthData[lowerAge].p95) * factor; } var dataToAdd = [ { percentile: "5th", weight: p5Weight.toFixed(2) }, { percentile: "50th (Median)", weight: p50Weight.toFixed(2) }, { percentile: "95th", weight: p95Weight.toFixed(2) } ]; // Add a row for the actual input weight and its calculated percentile var calculatedPercentile = parseFloat(document.getElementById('percentileRank').innerText); if (!isNaN(calculatedPercentile) && calculatedPercentile >= 5 && calculatedPercentile <= 95) { var actualWeight = parseFloat(document.getElementById('childWeightKg').value); if (!isNaN(actualWeight)) { dataToAdd.push({ percentile: "Your Child (" + calculatedPercentile + "th)", weight: actualWeight.toFixed(2) }); } } dataToAdd.forEach(function(item) { var row = tableBody.insertRow(); var cell1 = row.insertCell(0); var cell2 = row.insertCell(1); cell1.textContent = item.percentile; cell2.textContent = item.weight + " kg"; }); document.querySelector('#growthDataTableContainer h3').textContent = "Growth Data Table (for " + targetAge + " Months)"; } function updateChart() { var ctx = document.getElementById('weightChart').getContext('2d'); var inputAge = parseInt(document.getElementById('childAgeMonths').value); var inputWeight = parseFloat(document.getElementById('childWeightKg').value); if (myChart) { myChart.destroy(); // Destroy previous chart instance } // Prepare data for the chart var labels = chartData.map(function(d) { return d.ageMonths + ' mos'; }); var p5Data = chartData.map(function(d) { return d.p5; }); var p50Data = chartData.map(function(d) { return d.p50; }); var p95Data = chartData.map(function(d) { return d.p95; }); // Add the current input data point if it's not already represented clearly // We'll plot the user's current input point separately var currentDataPoint = { x: inputAge, y: inputWeight }; myChart = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: [{ label: '5th Percentile', data: p5Data, borderColor: 'rgba(255, 159, 64, 1)', backgroundColor: 'rgba(255, 159, 64, 0.2)', fill: false, tension: 0.1 }, { label: '50th Percentile (Median)', data: p50Data, borderColor: 'rgba(75, 192, 192, 1)', backgroundColor: 'rgba(75, 192, 192, 0.2)', fill: false, tension: 0.1 }, { label: '95th Percentile', data: p95Data, borderColor: 'rgba(153, 102, 255, 1)', backgroundColor: 'rgba(153, 102, 255, 0.2)', fill: false, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { x: { title: { display: true, text: 'Age (Months)' } }, y: { title: { display: true, text: 'Weight (kg)' }, beginAtZero: true // Ensure y-axis starts at 0 } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || ''; if (label) { label += ': '; } if (context.parsed.y !== null) { label += context.parsed.y + ' kg'; } return label; } } }, // Add a scatter point for the user's input annotation: { annotations: [{ type: 'point', xValue: inputAge, yValue: inputWeight, backgroundColor: 'rgba(0, 74, 153, 1)', borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 2, pointStyle: 'circle', radius: 5 }] } } } }); } function calculateWeight() { var ageMonthsInput = document.getElementById('childAgeMonths'); var weightKgInput = document.getElementById('childWeightKg'); var ageError = document.getElementById('ageError'); var weightError = document.getElementById('weightError'); // Reset errors ageError.textContent = ''; weightError.textContent = ''; var ageMonths = parseInt(ageMonthsInput.value); var weightKg = parseFloat(weightKgInput.value); // Validation if (isNaN(ageMonths) || ageMonths 240) { // 240 months = 20 years ageError.textContent = "Please enter a valid age between 0 and 240 months."; return; } if (isNaN(weightKg) || weightKg <= 0) { weightError.textContent = "Please enter a valid weight greater than 0 kg."; return; } // Calculations var healthyRange5 = getWeightForAge(ageMonths, 'p5'); var healthyRange95 = getWeightForAge(ageMonths, 'p95'); var percentile = getPercentileRank(ageMonths, weightKg); var status = getGrowthStatus(percentile); // Display Results document.getElementById('mainResult').innerText = percentile + "th Percentile"; document.getElementById('healthyRange').innerText = healthyRange5.toFixed(2) + " kg – " + healthyRange95.toFixed(2) + " kg"; document.getElementById('percentileRank').innerText = percentile + "th"; document.getElementById('growthStatus').innerText = status; // Update table and chart updateGrowthTable(ageMonths); updateChart(); // Pass input values to updateChart } function resetCalculator() { document.getElementById('childAgeMonths').value = 24; document.getElementById('childWeightKg').value = 12; document.getElementById('ageError').textContent = ''; document.getElementById('weightError').textContent = ''; // Reset results display document.getElementById('mainResult').innerText = "–"; document.getElementById('healthyRange').innerText = "–"; document.getElementById('percentileRank').innerText = "–"; document.getElementById('growthStatus').innerText = "–"; // Clear table document.getElementById('growthTableBody').innerHTML = ''; document.querySelector('#growthDataTableContainer h3').textContent = "Growth Data Table (Example)"; // Destroy chart if it exists if (myChart) { myChart.destroy(); myChart = null; } } function copyResults() { var mainResult = document.getElementById('mainResult').innerText; var healthyRange = document.getElementById('healthyRange').innerText; var percentileRank = document.getElementById('percentileRank').innerText; var growthStatus = document.getElementById('growthStatus').innerText; var ageInput = document.getElementById('childAgeMonths').value; var weightInput = document.getElementById('childWeightKg').value; if (mainResult === "–") { alert("No results to copy yet. Please calculate first."); return; } var assumptions = "Child's Age: " + ageInput + " months\n" + "Child's Weight: " + weightInput + " kg\n"; var resultsText = "— Child Weight Calculator Results —\n\n" + "Key Metrics:\n" + " Percentile Rank: " + percentileRank + "\n" + " Healthy Weight Range: " + healthyRange + "\n" + " Growth Status: " + growthStatus + "\n\n" + "Assumptions:\n" + assumptions; // Use prompt to copy, as the Clipboard API might not be available in all contexts var textArea = document.createElement("textarea"); textArea.value = resultsText; document.body.appendChild(textArea); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied to clipboard!' : 'Failed to copy results.'; alert(msg); } catch (err) { alert('Oops, unable to copy. Please copy manually.'); } document.body.removeChild(textArea); } // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { calculateWeight(); // Load Chart.js library dynamically if needed, or ensure it's included via CDN // For this example, assume Chart.js is available. If not, you'd load it here. // Example: loadScript('https://cdn.jsdelivr.net/npm/chart.js@3.9.1/dist/chart.min.js'); // Example: loadScript('https://cdn.jsdelivr.net/npm/chartjs-plugin-annotation@1.0.2/dist/chartjs-plugin-annotation.min.js'); }); // Helper to load scripts if Chart.js is not directly embedded /* function loadScript(url) { var script = document.createElement('script'); script.src = url; script.async = false; // Ensure scripts load in order if dependencies exist document.head.appendChild(script); } */ // Dummy Chart.js object if not loaded, to prevent JS errors during initial setup before calculation // In a real scenario, you'd ensure Chart.js is loaded before calling updateChart. if (typeof Chart === 'undefined') { var Chart = function() { this.destroy = function() {}; }; console.warn("Chart.js not found. Chart functionality will be disabled."); } // Dummy Annotation plugin if not loaded if (typeof Chart.register === 'undefined' || typeof Chart.register.annotation === 'undefined') { console.warn("Chart.js Annotation plugin not found. Scatter point may not display."); // Mock plugin registration if needed to avoid errors, though the chart won't render annotations. if (typeof Chart !== 'undefined' && Chart.defaults.plugins && typeof Chart.defaults.plugins.annotation === 'undefined') { Chart.defaults.plugins.annotation = {}; // Mock annotation plugin registration } }

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