Baby Weight Percentile Calculator (Boy) – Track Your Baby's Growth
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Baby Weight Percentile Calculator
Your Baby's Growth Results
Weight Percentile (Boy):
—
Age: — weeks
Weight: — kg
Growth Interpretation: —
Formula Explanation: This calculator uses standard WHO (World Health Organization) growth charts for boys. The percentile is determined by comparing your baby's weight for his age against a reference population of healthy boys. A percentile indicates that your baby weighs more than that percentage of babies of the same age and sex. For example, the 50th percentile means your baby weighs the same as 50% of other baby boys his age.
Weight-for-Age Chart (Boys)
Legend:
- Your Baby's Data Point
- 50th Percentile (Median)
- 3rd Percentile (Lower Limit)
- 97th Percentile (Upper Limit)
Growth Data Table
Weight Percentiles for Boys by Age (Approximate WHO Data)
| Age (Weeks) |
Weight (kg) – 3rd %ile |
Weight (kg) – 50th %ile |
Weight (kg) – 97th %ile |
What is a Baby Weight Percentile Calculator (Boy)?
A baby weight percentile calculator for boys is a specialized tool designed to help parents, caregivers, and healthcare professionals assess how a baby boy's weight compares to that of other boys of the same age. It doesn't measure absolute health but rather relative growth within a population. This baby weight percentile calculator boy uses data from established growth charts, typically those provided by organizations like the World Health Organization (WHO), to determine where your baby falls on the spectrum of typical weights for his age group.
Who should use it?
- Parents and guardians who want to monitor their baby boy's growth between pediatrician visits.
- Caregivers seeking to understand their baby's development relative to peers.
- Healthcare providers as a quick reference tool during check-ups.
Common misconceptions:
- Higher percentile is always better: This is untrue. A percentile simply indicates relative position. Both very high and very low percentiles can warrant attention, but the 50th percentile is considered the average, not necessarily the "ideal."
- Percentiles are rigid: Babies' percentiles can fluctuate, especially in the first year. A baby might be in the 75th percentile one month and the 60th the next, which is often perfectly normal as long as the growth trend is consistent and healthy.
- It replaces professional medical advice: This calculator is an informational tool. A pediatrician considers many factors beyond weight, including length, head circumference, feeding habits, activity level, and family history.
The core of a baby weight percentile calculator boy relies on statistical data derived from large-scale studies of infant growth. The World Health Organization (WHO) provides standardized growth charts that are widely used. These charts are based on longitudinal data collected from healthy, breastfed infants in diverse international settings.
Step-by-step derivation (Conceptual):
- Data Collection: Researchers collect weight data from a large sample of healthy baby boys at various ages.
- Distribution Analysis: For each specific age (e.g., 12 weeks), the collected weights are analyzed to understand their distribution. This typically involves plotting the weights and identifying key statistical points.
- Percentile Calculation: The data is used to establish specific weight values that correspond to different percentiles. For instance, the 3rd percentile represents the weight below which only 3% of baby boys of that age fall. The 50th percentile is the median weight, meaning half of the baby boys weigh less, and half weigh more. The 97th percentile represents the weight above which only 3% of baby boys fall.
- Interpolation: Since exact age measurements might not align perfectly with the data points on the chart, interpolation methods are often used by the calculator to estimate the percentile for a given weight and age.
Variable Explanations:
Variables Used in Percentile Calculation
| Variable |
Meaning |
Unit |
Typical Range (for calculation reference) |
| Age (A) |
The baby boy's age, typically measured in weeks or months from birth. |
Weeks |
0 – 104 weeks (approx. 2 years) |
| Weight (W) |
The baby boy's current weight. |
Kilograms (kg) |
0.5 kg – 20 kg (approx. range for first 2 years) |
| Reference Data |
Pre-established weight data points for specific percentiles (e.g., 3rd, 50th, 97th) at various ages for baby boys. |
Kilograms (kg) |
Varies by age |
| Percentile (P) |
The calculated position of the baby's weight relative to other baby boys of the same age. |
% |
0 – 100 |
The calculator essentially looks up the baby's age on the growth chart, finds the corresponding weight range for different percentiles, and determines where the baby's actual weight falls within that range to assign a percentile value. This is a complex statistical lookup and interpolation process, not a simple arithmetic formula like W / A.
Practical Examples (Real-World Use Cases)
Understanding the output of a baby weight percentile calculator boy is crucial for interpreting growth trends. Here are a couple of examples:
Example 1: A Growing Baby Boy
Scenario: Sarah's son, Leo, is 20 weeks old and weighs 8.2 kg. She uses the baby weight percentile calculator boy to see how he's doing.
Inputs:
- Baby's Age: 20 weeks
- Baby's Weight: 8.2 kg
- Sex: Boy
Calculator Output:
- Weight Percentile (Boy): 75th Percentile
- Age: 20 weeks
- Weight: 8.2 kg
- Growth Interpretation: Your baby boy's weight is above average for his age, placing him in the 75th percentile. This indicates he weighs more than 75% of baby boys his age. This is generally considered within a healthy range, especially if his length is also tracking well and he is meeting developmental milestones.
Interpretation: Leo is a robust baby boy. As long as he is active, feeding well, and developing appropriately, this percentile is likely normal for him. Sarah should discuss this with her pediatrician to ensure it aligns with Leo's overall health and growth pattern.
Example 2: A Baby Boy on the Lower End
Scenario: Mark and Emily's son, Noah, is 30 weeks old and weighs 6.5 kg. They are concerned about his weight gain and use the baby weight percentile calculator boy.
Inputs:
- Baby's Age: 30 weeks
- Baby's Weight: 6.5 kg
- Sex: Boy
Calculator Output:
- Weight Percentile (Boy): 10th Percentile
- Age: 30 weeks
- Weight: 6.5 kg
- Growth Interpretation: Your baby boy's weight is below average for his age, placing him in the 10th percentile. This indicates he weighs more than 10% of baby boys his age. While this percentile is on the lower side, it's important to consider his overall health, length, and development. Consistent growth along a percentile curve is often more important than the specific percentile number.
Interpretation: Noah is leaner compared to his peers. Mark and Emily should consult their pediatrician. The doctor will assess Noah's feeding, activity, and overall health to determine if any intervention or further investigation is needed. It's possible Noah is simply a naturally slim baby, but it's essential to rule out any underlying issues.
How to Use This Baby Weight Percentile Calculator (Boy)
Using our baby weight percentile calculator boy is straightforward. Follow these simple steps to get an understanding of your baby's growth:
- Enter Baby's Age: In the "Baby's Age (in Weeks)" field, input the number of completed weeks your baby boy has been alive. For example, if your baby is 3 months old, that's approximately 13 weeks.
- Enter Baby's Weight: In the "Baby's Weight (in Kilograms)" field, enter your baby's current weight in kilograms. Ensure you are using kilograms (kg) for accuracy.
- Click 'Calculate Percentile': Once both fields are filled, click the "Calculate Percentile" button.
How to Read Results:
- Weight Percentile (Boy): This is the primary result, showing the percentile rank of your baby's weight. A higher number means he weighs more relative to other boys his age.
- Age & Weight: These confirm the inputs you provided.
- Growth Interpretation: This provides a brief explanation of what the percentile means in simple terms (e.g., "above average," "below average," "around the average").
- Chart & Table: The accompanying chart and table offer a visual and data-driven comparison against standard growth curves.
Decision-Making Guidance:
- Consult Your Pediatrician: Always discuss your baby's growth results with your pediatrician. They can provide personalized advice based on your baby's unique health profile.
- Focus on Trends: Look at the growth trend over time rather than a single data point. Consistent growth along a percentile curve is generally a positive sign.
- Consider Other Factors: Remember that weight is just one aspect of growth. Length, head circumference, developmental milestones, and overall well-being are equally important.
- Use the Reset Button: If you need to recalculate or check different values, use the "Reset" button to clear the fields and start fresh.
- Copy Results: The "Copy Results" button is useful for saving or sharing the calculated information, perhaps to show your pediatrician.
Key Factors That Affect Baby Weight Percentile Results
While the baby weight percentile calculator boy provides a standardized comparison, several factors influence a baby's weight and, consequently, his percentile. Understanding these can provide context to the results:
- Genetics and Family History: Just like adults, babies inherit genetic predispositions for body type and growth rate. If parents are tall or have a larger build, their baby boy might naturally trend towards higher percentiles. Conversely, a family history of leaner builds might result in lower percentiles.
- Feeding Method and Intake: Whether a baby is breastfed or formula-fed, and the quantity consumed, significantly impacts weight gain. Breastfed babies might have slightly different growth patterns initially compared to formula-fed babies, though both can achieve healthy growth. Inadequate or excessive feeding can skew results.
- Prematurity: Babies born prematurely often have different growth trajectories. While corrected age is sometimes used, their initial weight and subsequent gain might place them on lower percentiles until they "catch up" physically.
- Health Conditions and Illnesses: Underlying medical conditions, infections, or digestive issues (like reflux or allergies) can affect a baby's appetite, nutrient absorption, and overall weight gain, leading to lower percentiles.
- Activity Level: As babies become more mobile (rolling, crawling), they burn more calories. A highly active baby might gain weight at a slightly slower pace compared to a less active one, potentially affecting their percentile.
- Length and Head Circumference: Weight percentiles are most meaningful when considered alongside length (or height) and head circumference percentiles. A baby consistently in the same percentile range across all three measurements (weight, length, head circumference) often indicates healthy, proportional growth. A significant discrepancy might warrant further medical evaluation.
- Metabolism: Individual metabolic rates vary. Some babies naturally process nutrients more efficiently, leading to faster weight gain, while others may have a slightly slower metabolism.
Frequently Asked Questions (FAQ)
Q1: What is the ideal weight percentile for a baby boy?
A: There isn't one single "ideal" percentile. The 50th percentile is the average. Both the 3rd and 97th percentiles are considered the lower and upper limits of normal by the WHO. Consistency in growth along a percentile curve is more important than hitting a specific number. Always consult your pediatrician.
Q2: My baby boy is in the 90th percentile. Should I be worried?
A: Not necessarily. A 90th percentile indicates he weighs more than 90% of baby boys his age. If he is otherwise healthy, active, meeting milestones, and his length is also tracking well, it might just mean he's a larger baby. Discuss it with your doctor to ensure proportional growth.
Q3: My baby boy is in the 5th percentile. Is he underweight?
A: A 5th percentile means he weighs more than only 5% of baby boys his age. While on the lower end, it's crucial to consider his overall health, feeding habits, and development. Your pediatrician will assess if intervention is needed. Sometimes, babies are just naturally leaner.
Q4: How often should I check my baby's weight percentile?
A: The best approach is to rely on your pediatrician's schedule for well-baby check-ups, where they track growth meticulously. Using a calculator frequently between visits can be helpful for monitoring, but avoid becoming overly anxious about daily or weekly fluctuations.
Q5: Does this calculator account for prematurity?
A: This calculator primarily uses the baby's chronological age. For premature babies, it's often recommended to use their 'corrected age' (age from the original due date) for growth assessments, especially in the first couple of years. Consult your pediatrician for the most accurate assessment using corrected age.
Q6: Can I use this calculator for my baby girl?
A: No, this specific calculator is designed for baby boys. Growth charts and percentile data differ between sexes. Please use a dedicated baby weight percentile calculator for girls if needed.
Q7: What if my baby's weight percentile changes significantly?
A: A sudden, significant jump or drop in percentile can be a reason to consult your pediatrician. It might indicate a change in feeding, a health issue, or a growth spurt. Consistent tracking and professional evaluation are key.
Q8: How accurate are these online calculators?
A: Online calculators like this one are generally accurate in applying standard growth chart data (like WHO or CDC). However, they rely on the accuracy of the data you input. For the most precise assessment, always refer to your pediatrician's measurements and professional judgment.
// — Data for WHO Growth Charts (Boys) —
// Approximate data points for weight in kg for boys at different ages in weeks.
// This is a simplified representation for demonstration. Real charts are more complex curves.
// Format: { age_weeks: [3rd_percentile_kg, 50th_percentile_kg, 97th_percentile_kg] }
var whoGrowthDataBoys = {
0: [2.5, 3.5, 4.8], // Birth
4: [3.5, 5.0, 6.5], // 4 Weeks
8: [4.5, 6.0, 7.8], // 8 Weeks
12: [5.2, 6.8, 8.5], // 12 Weeks
16: [5.8, 7.4, 9.2], // 16 Weeks
20: [6.3, 8.0, 9.8], // 20 Weeks
24: [6.7, 8.5, 10.3], // 24 Weeks
28: [7.0, 8.9, 10.8], // 28 Weeks
32: [7.3, 9.2, 11.2], // 32 Weeks
36: [7.5, 9.5, 11.5], // 36 Weeks
40: [7.7, 9.7, 11.8], // 40 Weeks
44: [7.9, 9.9, 12.0], // 44 Weeks
48: [8.0, 10.1, 12.2], // 48 Weeks
52: [8.1, 10.2, 12.4], // 52 Weeks (1 Year)
// Add more data points up to ~2 years (104 weeks) if needed for more granularity
60: [8.5, 10.8, 13.0], // ~14 months
78: [9.0, 11.5, 14.0], // ~18 months
96: [9.5, 12.0, 15.0], // ~22 months
104: [9.8, 12.3, 15.5] // ~2 years
};
var chartInstance = null; // To hold the chart instance
function getGrowthData(ageWeeks) {
var lowerAge = 0;
var upperAge = 104; // Max age in our data
var lowerData = whoGrowthDataBoys[0];
var upperData = whoGrowthDataBoys[104];
// Find the closest data points for interpolation
var ages = Object.keys(whoGrowthDataBoys).map(Number).sort(function(a, b) { return a – b; });
for (var i = 0; i < ages.length; i++) {
if (ages[i] = ageWeeks) {
upperAge = ages[i];
upperData = whoGrowthDataBoys[upperAge];
break; // Found the upper bound
}
}
// If ageWeeks is exactly one of the keys
if (lowerAge === upperAge) {
return lowerData;
}
// Interpolate if ageWeeks is between two data points
var ageRange = upperAge – lowerAge;
var ageOffset = ageWeeks – lowerAge;
var fraction = ageRange === 0 ? 0 : ageOffset / ageRange;
var interpolatedWeight3rd = lowerData[0] + fraction * (upperData[0] – lowerData[0]);
var interpolatedWeight50th = lowerData[1] + fraction * (upperData[1] – lowerData[1]);
var interpolatedWeight97th = lowerData[2] + fraction * (upperData[2] – lowerData[2]);
return [interpolatedWeight3rd, interpolatedWeight50th, interpolatedWeight97th];
}
function calculatePercentile() {
var ageWeeksInput = document.getElementById("babyAge");
var weightKgInput = document.getElementById("babyWeight");
var resultsDiv = document.getElementById("results");
var weightPercentileResultDiv = document.getElementById("weightPercentileResult");
var resultAgeSpan = document.getElementById("resultAge");
var resultWeightSpan = document.getElementById("resultWeight");
var growthInterpretationSpan = document.getElementById("growthInterpretation");
var growthChartSection = document.getElementById("growthChartSection");
var growthDataTableSection = document.getElementById("growthDataTableSection");
var ageWeeksError = document.getElementById("babyAgeError");
var weightKgError = document.getElementById("babyWeightError");
// Reset errors
ageWeeksError.style.display = 'none';
weightKgError.style.display = 'none';
resultsDiv.style.display = 'none';
growthChartSection.style.display = 'none';
growthDataTableSection.style.display = 'none';
var ageWeeks = parseFloat(ageWeeksInput.value);
var weightKg = parseFloat(weightKgInput.value);
var isValid = true;
if (isNaN(ageWeeks) || ageWeeks < 0) {
ageWeeksError.textContent = "Please enter a valid age in weeks (0 or greater).";
ageWeeksError.style.display = 'block';
isValid = false;
}
if (isNaN(weightKg) || weightKg <= 0) {
weightKgError.textContent = "Please enter a valid weight in kilograms (greater than 0).";
weightKgError.style.display = 'block';
isValid = false;
}
if (!isValid) {
return;
}
// Get reference weights for the given age
var referenceWeights = getGrowthData(ageWeeks);
if (!referenceWeights) {
ageWeeksError.textContent = "Data not available for this age. Please try an age between 0 and 104 weeks.";
ageWeeksError.style.display = 'block';
return;
}
var weight3rd = referenceWeights[0];
var weight50th = referenceWeights[1];
var weight97th = referenceWeights[2];
var percentile = "–";
var interpretation = "–";
if (weightKg < weight3rd) {
percentile = "< 3";
interpretation = "Significantly below average. Consult your pediatrician.";
} else if (weightKg < weight50th) {
// Interpolate percentile between 3rd and 50th
percentile = Math.round(3 + ((weightKg – weight3rd) / (weight50th – weight3rd)) * 47);
interpretation = "Below average. Monitor growth with your pediatrician.";
} else if (weightKg 97″;
interpretation = "Significantly above average. Consult your pediatrician.";
}
// Ensure percentile is within bounds if calculation is slightly off
if (percentile !== "–") {
percentile = Math.max(1, Math.min(99, parseInt(percentile)));
}
// Display results
weightPercentileResultDiv.textContent = percentile + "th";
resultAgeSpan.textContent = ageWeeks.toFixed(1);
resultWeightSpan.textContent = weightKg.toFixed(2);
growthInterpretationSpan.textContent = interpretation;
resultsDiv.style.display = 'block';
// Update chart and table
updateGrowthChart(ageWeeks, weightKg, referenceWeights);
populateGrowthTable(ageWeeks);
growthChartSection.style.display = 'block';
growthDataTableSection.style.display = 'block';
}
function updateGrowthChart(currentAge, currentWeight, referenceWeights) {
var ctx = document.getElementById('growthChartCanvas').getContext('2d');
// Destroy previous chart instance if it exists
if (chartInstance) {
chartInstance.destroy();
}
var ages = Object.keys(whoGrowthDataBoys).map(Number).sort(function(a, b) { return a – b; });
var weights3rd = ages.map(function(age) { return whoGrowthDataBoys[age][0]; });
var weights50th = ages.map(function(age) { return whoGrowthDataBoys[age][1]; });
var weights97th = ages.map(function(age) { return whoGrowthDataBoys[age][2]; });
// Ensure current age is included for the data point
var chartAges = […ages];
var chartWeights3rd = […weights3rd];
var chartWeights50th = […weights50th];
var chartWeights97th = […weights97th];
// Add current data point if not already present
if (chartAges.indexOf(currentAge) === -1) {
chartAges.push(currentAge);
chartWeights3rd.push(referenceWeights[0]);
chartWeights50th.push(referenceWeights[1]);
chartWeights97th.push(referenceWeights[2]);
// Sort again after adding
var combined = chartAges.map(function(age, i) { return { age: age, w3: chartWeights3rd[i], w50: chartWeights50th[i], w97: chartWeights97th[i] }; });
combined.sort(function(a, b) { return a.age – b.age; });
chartAges = combined.map(function(item) { return item.age; });
chartWeights3rd = combined.map(function(item) { return item.w3; });
chartWeights50th = combined.map(function(item) { return item.w50; });
chartWeights97th = combined.map(function(item) { return item.w97; });
}
// Find the index for the current age to plot the point
var currentAgeIndex = chartAges.indexOf(currentAge);
chartInstance = new Chart(ctx, {
type: 'line',
data: {
labels: chartAges,
datasets: [{
label: '3rd Percentile',
data: chartWeights3rd,
borderColor: '#dc3545', // Red
backgroundColor: 'rgba(220, 53, 69, 0.1)',
fill: false,
tension: 0.1,
pointRadius: 0 // Hide default points on lines
}, {
label: '50th Percentile (Median)',
data: chartWeights50th,
borderColor: '#ffc107', // Yellow
backgroundColor: 'rgba(255, 193, 7, 0.1)',
fill: false,
tension: 0.1,
pointRadius: 0
}, {
label: '97th Percentile',
data: chartWeights97th,
borderColor: '#28a745', // Green
backgroundColor: 'rgba(40, 167, 69, 0.1)',
fill: false,
tension: 0.1,
pointRadius: 0
}, {
label: 'Your Baby\'s Weight',
data: chartAges.map(function(age, index) {
// Plot only the current baby's point
return age === currentAge ? currentWeight : null;
}),
borderColor: 'var(–primary-color)', // Blue
backgroundColor: 'var(–primary-color)',
fill: false,
tension: 0,
pointRadius: 6, // Make the point visible
pointHoverRadius: 8
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
x: {
title: {
display: true,
text: 'Age (Weeks)'
},
min: 0,
max: 104 // Max age displayed
},
y: {
title: {
display: true,
text: 'Weight (kg)'
},
min: 0, // Start y-axis at 0
// Dynamically set max based on data, ensuring it covers the highest point
max: Math.max(…chartWeights97th, currentWeight) * 1.1 // Add 10% buffer
}
},
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) + ' kg';
}
return label;
}
}
},
legend: {
position: 'top',
}
}
}
});
}
function populateGrowthTable(currentAge) {
var tableBody = document.getElementById("growthTableBody");
tableBody.innerHTML = "; // Clear existing rows
var ages = Object.keys(whoGrowthDataBoys).map(Number).sort(function(a, b) { return a – b; });
// Add current age data point if it's not in the predefined list
if (ages.indexOf(currentAge) === -1) {
var referenceWeights = getGrowthData(currentAge);
if (referenceWeights) {
ages.push(currentAge);
ages.sort(function(a, b) { return a – b; }); // Re-sort
}
}
// Limit table to a reasonable number of points for readability, e.g., every 4 weeks
var displayedAges = ages.filter(function(age, index) {
return index % 4 === 0 || age === currentAge || age === ages[ages.length – 1];
});
// Ensure currentAge is always included if not already
if (displayedAges.indexOf(currentAge) === -1 && currentAge >= 0 && currentAge <= 104) {
displayedAges.push(currentAge);
displayedAges.sort(function(a, b) { return a – b; });
}
displayedAges.forEach(function(age) {
var referenceWeights = getGrowthData(age);
if (referenceWeights) {
var row = tableBody.insertRow();
var cellAge = row.insertCell();
var cell3rd = row.insertCell();
var cell50th = row.insertCell();
var cell97th = row.insertCell();
cellAge.textContent = age + " weeks";
cell3rd.textContent = referenceWeights[0].toFixed(2) + " kg";
cell50th.textContent = referenceWeights[1].toFixed(2) + " kg";
cell97th.textContent = referenceWeights[2].toFixed(2) + " kg";
// Highlight the row corresponding to the current age
if (age === currentAge) {
row.style.backgroundColor = "#e9f7ec"; // Light green highlight
cellAge.style.fontWeight = "bold";
}
}
});
}
function resetCalculator() {
document.getElementById("babyAge").value = "";
document.getElementById("babyWeight").value = "";
document.getElementById("babyAgeError").textContent = "";
document.getElementById("babyAgeError").style.display = 'none';
document.getElementById("babyWeightError").textContent = "";
document.getElementById("babyWeightError").style.display = 'none';
document.getElementById("results").style.display = 'none';
document.getElementById("growthChartSection").style.display = 'none';
document.getElementById("growthDataTableSection").style.display = 'none';
if (chartInstance) {
chartInstance.destroy();
chartInstance = null;
}
}
function copyResults() {
var percentile = document.getElementById("weightPercentileResult").textContent;
var age = document.getElementById("resultAge").textContent;
var weight = document.getElementById("resultWeight").textContent;
var interpretation = document.getElementById("growthInterpretation").textContent;
if (percentile === "–") {
alert("No results to copy yet. Please calculate first.");
return;
}
var resultText = "Baby Weight Percentile Results (Boy):\n\n" +
"Age: " + age + " weeks\n" +
"Weight: " + weight + " kg\n" +
"Weight Percentile: " + percentile + "\n" +
"Interpretation: " + interpretation + "\n\n" +
"Key Assumptions:\n" +
"- Based on WHO growth standards for boys.\n" +
"- Percentile is a comparison to other boys of the same age.";
// Use navigator.clipboard for modern browsers
if (navigator.clipboard && navigator.clipboard.writeText) {
navigator.clipboard.writeText(resultText).then(function() {
alert('Results copied to clipboard!');
}).catch(function(err) {
console.error('Failed to copy text: ', err);
// Fallback for older browsers or if clipboard API fails
copyToClipboardFallback(resultText);
});
} else {
// Fallback for older browsers
copyToClipboardFallback(resultText);
}
}
function copyToClipboardFallback(text) {
var textArea = document.createElement("textarea");
textArea.value = text;
textArea.style.position = "fixed"; // Avoid scrolling to bottom
textArea.style.left = "-9999px";
textArea.style.top = "-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.';
alert(msg);
} catch (err) {
console.error('Fallback: Oops, unable to copy', err);
alert('Failed to copy results. Please copy manually.');
}
document.body.removeChild(textArea);
}
// Load Chart.js library dynamically if not already present
function loadChartJs() {
if (typeof Chart === 'undefined') {
var script = document.createElement('script');
script.src = 'https://cdn.jsdelivr.net/npm/chart.js@3.7.0/dist/chart.min.js'; // Use a specific version
script.onload = function() {
console.log('Chart.js loaded.');
// Optionally, trigger an initial calculation or chart update if needed on load
};
script.onerror = function() {
console.error('Failed to load Chart.js library.');
alert('Error loading charting library. Charts may not display correctly.');
};
document.head.appendChild(script);
}
}
// Load Chart.js when the page loads
window.onload = loadChartJs;