Baby Boy Weight Chart Calculator

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Monitor your baby boy’s growth against standard percentiles.

Growth Calculator

Typical Baby Boy Growth Data (WHO Standards)

Age (Months)	Avg. Weight (kg)	3rd %ile Weight (kg)	97th %ile Weight (kg)	Avg. Length (cm)	3rd %ile Length (cm)	97th %ile Length (cm)
0	3.5	2.5	4.8	49.9	46.0	53.8
1	4.5	3.2	5.9	54.0	50.0	57.9
2	5.5	4.0	7.0	57.9	53.0	61.7
3	6.3	4.7	7.9	61.3	55.7	64.9
4	7.0	5.3	8.7	64.2	58.0	67.6
5	7.5	5.8	9.3	66.6	59.9	70.0
6	7.9	6.2	9.8	68.6	61.5	72.1
7	8.3	6.5	10.3	70.3	63.0	73.9
8	8.6	6.8	10.7	71.8	64.3	75.6
9	8.9	7.0	11.1	73.2	65.6	77.2
10	9.1	7.3	11.5	74.5	66.8	78.7
11	9.3	7.5	11.8	75.7	67.9	80.1
12	9.5	7.7	12.1	76.8	69.0	81.5

Bringing a baby boy home is an incredibly joyous occasion. As parents, one of the most common concerns and points of interest is their child’s growth and development. Ensuring your little one is growing at a healthy pace is paramount. A baby boy weight chart calculator can be an invaluable tool for parents to understand how their son’s measurements stack up against established growth standards. This isn’t about comparison for competition’s sake, but rather about gaining peace of mind and identifying potential areas where professional advice might be beneficial. Understanding these growth metrics, like weight and length percentiles, is a crucial part of monitoring your baby’s overall well-being.

What is a Baby Boy Weight Chart Calculator?

A baby boy weight chart calculator is an online tool designed to help parents and caregivers assess a baby boy’s weight and length against the World Health Organization (WHO) growth standards. These standards are based on extensive data collected from healthy, breastfed infants around the world. The calculator takes the baby’s age (in months), weight (in kilograms), and length (in centimeters) as inputs and outputs key growth indicators, primarily weight and length percentiles.

Who should use it?

• New parents seeking to understand their baby’s growth patterns.
• Caregivers monitoring a baby’s development.
• Parents who want to track their baby boy’s progress between pediatrician visits.
• Anyone looking for a quick, accessible way to interpret growth measurements.

Common misconceptions:

• Misconception 1: A low percentile means something is wrong. In reality, babies grow at different rates. A baby consistently in the 10th percentile is growing just as healthily as a baby consistently in the 90th percentile, provided they are following their own growth curve.
• Misconception 2: All babies should be plump. Healthy babies come in all shapes and sizes. The goal is healthy growth, not achieving a specific look.
• Misconception 3: The calculator replaces a doctor’s advice. This tool is for informational purposes. Always consult your pediatrician for personalized health and growth assessments.

Baby Boy Weight Chart Calculator Formula and Mathematical Explanation

The core of the baby boy weight chart calculator relies on comparing the provided measurements against established growth curves. While the exact calculation of percentiles from raw data can be complex, involving statistical modeling like the LMS (Lambda-Mu-Sigma) method used by WHO, the calculator simplifies this by using pre-computed tables or simplified approximations. The key outputs are:

1. Weight Percentile: This indicates the percentage of baby boys of the same age whose weight is *less than* your baby’s weight. For example, a 50th percentile means your baby weighs the same as 50% of other baby boys his age.
2. Length Percentile: Similarly, this shows the percentage of baby boys of the same age whose length is *less than* your baby’s length.
3. BMI (Body Mass Index): Calculated using the formula: BMI = weight (kg) / (length (m))^2. This gives an indication of body composition. Note that BMI interpretation in infants is different from adults and often considered alongside weight and length percentiles.

Variable Explanations:

Let’s break down the variables used in our calculator:

Variable	Meaning	Unit	Typical Range (0-12 Months)
Age	The baby boy’s age in completed months.	Months	0 – 12
Weight	The baby boy’s current body mass.	Kilograms (kg)	~2.5 kg to ~12.1 kg
Length	The baby boy’s recumbent length (head to heel).	Centimeters (cm)	~46.0 cm to ~81.5 cm
Weight Percentile	Percentage of baby boys of the same age weighing less.	%	0 – 100
Length Percentile	Percentage of baby boys of the same age measuring shorter.	%	0 – 100
BMI	Body Mass Index, a ratio of weight to height squared.	kg/m²	~12.0 to ~20.0 (highly variable in infancy)

Note: The ‘Typical Range’ for percentiles is 0-100%. The BMI range is approximate and highly dependent on age and individual growth patterns. The calculator uses WHO data for precise percentile determination.

Practical Examples (Real-World Use Cases)

Let’s illustrate how the baby boy weight chart calculator works with realistic scenarios:

Example 1: A 6-Month-Old Baby

Inputs:

• Age: 6 months
• Weight: 7.9 kg
• Length: 68.6 cm

Calculator Output:

• Weight Percentile: 50th %ile
• Length Percentile: 50th %ile
• BMI: ~16.9 kg/m²
• Primary Result Interpretation: This baby boy is growing right on track, with both his weight and length matching the average for 6-month-old boys according to WHO standards.

Interpretation: This is excellent! The baby is following the standard growth curve perfectly. This indicates a healthy growth pattern and sufficient intake. The BMI is also within a typical range for this age.

Example 2: A 3-Month-Old Baby at the Higher End

Inputs:

• Age: 3 months
• Weight: 7.5 kg
• Length: 63 cm

Calculator Output:

• Weight Percentile: ~90th %ile
• Length Percentile: ~85th %ile
• BMI: ~18.8 kg/m²
• Primary Result Interpretation: This baby boy is on the larger side for his age, weighing more than approximately 90% of 3-month-old boys and measuring longer than about 85%.

Interpretation: While this baby is above the 50th percentile, his consistent position in the higher percentiles suggests a healthy, albeit robust, growth trajectory. His pediatrician would monitor this trend to ensure it remains stable. The BMI is also higher, which is common for babies growing well in both weight and length.

How to Use This Baby Boy Weight Chart Calculator

Using our baby boy weight chart calculator is straightforward. Follow these simple steps to get an instant growth assessment:

1. Input Age: Enter the baby boy’s exact age in completed months (e.g., if he is 5 months and 2 weeks old, enter 5).
2. Input Weight: Accurately measure and enter your baby’s current weight in kilograms (kg). If you only have pounds, convert it (1 kg ≈ 2.2 lbs).
3. Input Length: Measure your baby’s length from head to toe in centimeters (cm). If you have inches, convert them (1 inch ≈ 2.54 cm).
4. Calculate: Click the “Calculate Percentile” button.

How to read results:

• Primary Result: This highlights your baby’s overall growth status relative to the average. For example, “50th Percentile – On Track” or “90th Percentile – Above Average Growth”.
• Weight Percentile & Length Percentile: These numbers tell you the percentage of baby boys of the same age who are smaller than your son. A percentile around 50% is average. Percentiles consistently below 3% or above 97% might warrant a discussion with your pediatrician.
• BMI: This provides another metric, but should be interpreted cautiously in infants.
• Growth Chart: The dynamic chart visually represents your baby’s measurements against the WHO growth curves, allowing you to see their position at a glance.

Decision-making guidance:

• Consistent Growth: If your baby consistently falls within a specific percentile range (e.g., always between 25th and 75th), this usually indicates healthy, steady growth.
• Crossing Percentiles: If your baby’s measurements suddenly jump significantly across multiple percentiles (e.g., from 50th to 90th, or 75th to 10th) over a short period, it’s advisable to consult your pediatrician.
• Extreme Percentiles: Percentiles below the 3rd or above the 97th are considered outside the typical range and should be discussed with a healthcare professional.

Remember, these are guidelines. Your pediatrician is the best resource for interpreting your child’s unique growth patterns. For more insights on infant nutrition, consider our infant feeding guide.

Key Factors That Affect Baby Boy Growth Results

While the baby boy weight chart calculator provides a snapshot based on measurements, several underlying factors influence these growth metrics. Understanding these can provide a more holistic view:

1. Genetics: Just like adults, babies inherit genetic predispositions for height and build. If parents are tall, their baby boy is likely to be taller than average.
2. Nutrition and Feeding: This is perhaps the most critical factor. Adequate intake of breast milk or formula is essential. For breastfed babies, ensuring a good latch and sufficient milk supply is key. For formula-fed babies, using the correct preparation and ensuring adequate volume are important. Poor absorption due to digestive issues can also impact weight gain.
3. Prenatal Health and Birth Weight: A baby’s health and weight at birth can set the initial trajectory. Premature babies or those born with specific conditions may follow different growth curves initially.
4. Health Conditions: Underlying medical issues, such as infections, chronic illnesses, or hormonal imbalances, can significantly affect a baby’s appetite, nutrient absorption, and overall growth rate.
5. Sleep Patterns: Adequate sleep is crucial for growth, as growth hormones are primarily released during sleep. Disruptions in sleep can potentially impact growth over time.
6. Physical Activity and Development: While less impactful on weight/length percentiles in early infancy compared to nutrition, a baby’s overall health, energy levels, and milestones can correlate with well-being and growth.
7. Maternal Health During Pregnancy: Factors like maternal nutrition, exposure to certain substances, and conditions like gestational diabetes can influence fetal growth and birth weight, setting the stage for postnatal growth.
8. Environmental Factors: Less direct, but factors like exposure to illness, stress levels in the household, and access to healthcare can indirectly influence a baby’s growth and development.

Monitoring these factors alongside percentile tracking can offer a comprehensive understanding of your baby boy’s development. For more on optimal infant nutrition, explore our guide to baby-led weaning.

Frequently Asked Questions (FAQ)

What are WHO growth standards and why are they used?

The WHO growth standards are a set of curves representing optimal growth for infants and young children under healthy conditions. They are used globally because they are based on large, international studies of healthy, well-nourished infants, providing a reliable benchmark for comparison.

My baby boy is in the 97th percentile for weight. Is this a concern?

Being in the 97th percentile means your baby weighs more than 97% of other baby boys his age. This isn’t automatically a concern if it’s consistent with his growth pattern and he is otherwise healthy and meeting milestones. However, significant and rapid increases in percentiles, or consistently high percentiles combined with other factors, should be discussed with your pediatrician.

What if my baby’s weight and length percentiles are very different?

A significant difference (e.g., high weight percentile and low length percentile) might indicate that the baby is gaining weight faster than he is growing taller. This could be due to various reasons, including feeding patterns or underlying metabolic factors. It’s a good point to bring up with your pediatrician for assessment.

How often should I use the baby boy weight chart calculator?

You can use the calculator whenever you have new measurements, perhaps after a check-up or when you’re curious. However, avoid over-analyzing daily fluctuations. Frequent checks are useful, but focus on the overall trend over weeks and months. It’s best used in conjunction with, not as a replacement for, your pediatrician’s guidance.

Does this calculator account for premature babies?

This calculator uses standard WHO growth charts, which are primarily for full-term infants. For premature babies, growth is often assessed using corrected age and specialized charts provided by healthcare professionals. Consult your pediatrician for the most accurate assessment of premature infant growth. You might find our guide to premature baby care helpful.

What’s the difference between percentiles and percentages?

In growth charts, a percentile (like 50th percentile) indicates the rank compared to others in the same group. It means 50% of individuals are below that point and 50% are above. A simple percentage usually refers to a proportion out of 100 in a different context. For growth, percentile is the key term.

Is a BMI calculation relevant for infants?

Yes, BMI is calculated for infants, but its interpretation differs significantly from adults. It’s used as one of several indicators alongside weight and length percentiles. A high infant BMI doesn’t necessarily predict adult obesity but is monitored as part of overall growth. Consulting a pediatrician is essential for interpreting infant BMI. Consider checking out our childhood nutrition tips.

Can this calculator be used for baby girls?

No, this specific calculator is tailored for baby boys using the WHO growth standards for boys. Separate growth charts and calculators exist for baby girls, as their growth patterns differ slightly.

What are the ideal growth percentiles for a baby boy?

There isn’t one single “ideal” percentile. The most important factor is consistent growth along the baby’s own curve. While the 50th percentile represents the average, babies consistently tracking anywhere between the 3rd and 97th percentile are generally considered to be growing healthily, provided they are meeting developmental milestones and have no underlying health issues. Understanding baby milestones can complement growth tracking.

Related Tools and Internal Resources

• Baby Girl Weight Chart Calculator

  Compare your baby girl’s measurements against standard growth charts.

• Infant Feeding Guide

  Learn about optimal nutrition for babies during their first year.

• Childhood Nutrition Tips

  Discover age-appropriate nutritional advice for growing children.

• Baby Milestones Tracker

  Monitor your baby’s key developmental milestones beyond just physical growth.

• Premature Baby Care Guide

  Essential information for parents of premature infants.

• Guide to Baby-Led Weaning

  Explore methods for introducing solid foods to your baby.

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return true;
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function getWeightPercentile(age, weight) {
// Simplified percentile calculation based on WHO data for 0-12 months
// This is a highly simplified approximation. Accurate percentiles require complex LMS methods.
// Using piecewise linear interpolation based on provided table data.
var data = [
{ age: 0, p3: 2.5, p50: 3.5, p97: 4.8 },
{ age: 1, p3: 3.2, p50: 4.5, p97: 5.9 },
{ age: 2, p3: 4.0, p50: 5.5, p97: 7.0 },
{ age: 3, p3: 4.7, p50: 6.3, p97: 7.9 },
{ age: 4, p3: 5.3, p50: 7.0, p97: 8.7 },
{ age: 5, p3: 5.8, p50: 7.5, p97: 9.3 },
{ age: 6, p3: 6.2, p50: 7.9, p97: 9.8 },
{ age: 7, p3: 6.5, p50: 8.3, p97: 10.3 },
{ age: 8, p3: 6.8, p50: 8.6, p97: 10.7 },
{ age: 9, p3: 7.0, p50: 8.9, p97: 11.1 },
{ age: 10, p3: 7.3, p50: 9.1, p97: 11.5 },
{ age: 11, p3: 7.5, p50: 9.3, p97: 11.8 },
{ age: 12, p3: 7.7, p50: 9.5, p97: 12.1 }
];

// Find the data points surrounding the given age
var lowerData = data[0];
var upperData = data[data.length – 1];

for (var i = 0; i = data[i].age && age <= data[i+1].age) {
lowerData = data[i];
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break;
}
}
if (age data[data.length – 1].age) return { p3: data[data.length – 1].p3, p50: data[data.length – 1].p50, p97: data[data.length – 1].p97 };

var ageDiff = upperData.age – lowerData.age;
var weightDiff = upperData.p50 – lowerData.p50;
var ageRatio = (age – lowerData.age) / ageDiff;

var avgWeight = lowerData.p50 + (ageRatio * weightDiff);

// Crude percentile estimation
if (weight < avgWeight * 0.8) return 'Low'; // Placeholder for avgWeight * 1.2) return ‘High’; // Placeholder for >97th percentile logic
if (weight avgWeight * 1.1) return ‘Above Average’;
return ‘Average’; // 50th percentile approximation

}

function getLengthPercentile(age, length) {
// Simplified percentile calculation based on WHO data for 0-12 months
var data = [
{ age: 0, p3: 46.0, p50: 49.9, p97: 53.8 },
{ age: 1, p3: 50.0, p50: 54.0, p97: 57.9 },
{ age: 2, p3: 53.0, p50: 57.9, p97: 61.7 },
{ age: 3, p3: 55.7, p50: 61.3, p97: 64.9 },
{ age: 4, p3: 58.0, p50: 64.2, p97: 67.6 },
{ age: 5, p3: 59.9, p50: 66.6, p97: 70.0 },
{ age: 6, p3: 61.5, p50: 68.6, p97: 72.1 },
{ age: 7, p3: 63.0, p50: 70.3, p97: 73.9 },
{ age: 8, p3: 64.3, p50: 71.8, p97: 75.6 },
{ age: 9, p3: 65.6, p50: 73.2, p97: 77.2 },
{ age: 10, p3: 66.8, p50: 74.5, p97: 78.7 },
{ age: 11, p3: 67.9, p50: 75.7, p97: 80.1 },
{ age: 12, p3: 69.0, p50: 76.8, p97: 81.5 }
];

// Find the data points surrounding the given age
var lowerData = data[0];
var upperData = data[data.length – 1];

for (var i = 0; i = data[i].age && age <= data[i+1].age) {
lowerData = data[i];
upperData = data[i+1];
break;
}
}
if (age data[data.length – 1].age) return { p3: data[data.length – 1].p3, p50: data[data.length – 1].p50, p97: data[data.length – 1].p97 };

var ageDiff = upperData.age – lowerData.age;
var lengthDiff = upperData.p50 – lowerData.p50;
var ageRatio = (age – lowerData.age) / ageDiff;

var avgLength = lowerData.p50 + (ageRatio * lengthDiff);

// Crude percentile estimation
if (length < avgLength * 0.9) return 'Low'; // Placeholder for avgLength * 1.1) return ‘High’; // Placeholder for >97th percentile logic
if (length avgLength * 1.05) return ‘Above Average’;
return ‘Average’; // 50th percentile approximation
}

function calculateBMI(weightKg, lengthCm) {
if (weightKg <= 0 || lengthCm <= 0) return NaN;
var lengthM = lengthCm / 100;
return weightKg / (lengthM * lengthM);
}

var myChart = null; // Initialize chart variable

function updateChart(age, weight, length) {
var ctx = document.getElementById('growthChart').getContext('2d');

// Destroy previous chart instance if it exists
if (myChart) {
myChart.destroy();
}

var chartData = [
{ age: 0, p3W: 2.5, p50W: 3.5, p97W: 4.8, p3L: 46.0, p50L: 49.9, p97L: 53.8 },
{ age: 1, p3W: 3.2, p50W: 4.5, p97W: 5.9, p3L: 50.0, p50L: 54.0, p97L: 57.9 },
{ age: 2, p3W: 4.0, p50W: 5.5, p97W: 7.0, p3L: 53.0, p50L: 57.9, p97L: 61.7 },
{ age: 3, p3W: 4.7, p50W: 6.3, p97W: 7.9, p3L: 55.7, p50L: 61.3, p97L: 64.9 },
{ age: 4, p3W: 5.3, p50W: 7.0, p97W: 8.7, p3L: 58.0, p50L: 64.2, p97L: 67.6 },
{ age: 5, p3W: 5.8, p50W: 7.5, p97W: 9.3, p3L: 59.9, p50L: 66.6, p97L: 70.0 },
{ age: 6, p3W: 6.2, p50W: 7.9, p97W: 9.8, p3L: 61.5, p50L: 68.6, p97L: 72.1 },
{ age: 7, p3W: 6.5, p50W: 8.3, p97W: 10.3, p3L: 63.0, p50L: 70.3, p97L: 73.9 },
{ age: 8, p3W: 6.8, p50W: 8.6, p97W: 10.7, p3L: 64.3, p50L: 71.8, p97L: 75.6 },
{ age: 9, p3W: 7.0, p50W: 8.9, p97W: 11.1, p3L: 65.6, p50L: 73.2, p97L: 77.2 },
{ age: 10, p3W: 7.3, p50W: 9.1, p97W: 11.5, p3L: 66.8, p50L: 74.5, p97L: 78.7 },
{ age: 11, p3W: 7.5, p50W: 9.3, p97W: 11.8, p3L: 67.9, p50L: 75.7, p97L: 80.1 },
{ age: 12, p3W: 7.7, p50W: 9.5, p97W: 12.1, p3L: 69.0, p50L: 76.8, p97L: 81.5 }
];

var labels = chartData.map(function(d) { return d.age + 'mo'; });
var p3WData = chartData.map(function(d) { return d.p3W; });
var p50WData = chartData.map(function(d) { return d.p50W; });
var p97WData = chartData.map(function(d) { return d.p97W; });
var p3LData = chartData.map(function(d) { return d.p3L; });
var p50LData = chartData.map(function(d) { return d.p50L; });
var p97LData = chartData.map(function(d) { return d.p97L; });

// Highlight the user's data point
var userPointData = {
x: age,
y: weight,
borderColor: 'orange',
backgroundColor: 'rgba(255, 165, 0, 0.5)',
pointRadius: 6,
pointHoverRadius: 8
};

myChart = new Chart(ctx, {
type: 'line',
data: {
labels: labels,
datasets: [
{
label: 'Weight (3rd %ile)',
data: p3WData,
borderColor: 'rgba(0, 74, 153, 0.6)',
backgroundColor: 'rgba(0, 74, 153, 0.1)',
fill: false,
borderDash: [5, 5]
},
{
label: 'Weight (50th %ile)',
data: p50WData,
borderColor: 'rgba(40, 167, 69, 0.8)',
backgroundColor: 'rgba(40, 167, 69, 0.1)',
fill: false
},
{
label: 'Weight (97th %ile)',
data: p97WData,
borderColor: 'rgba(220, 53, 69, 0.6)',
backgroundColor: 'rgba(220, 53, 69, 0.1)',
fill: false,
borderDash: [5, 5]
},
// Length Data Series (optional, can add complexity to visualization)
// For simplicity, focusing on weight percentiles for this chart
]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
x: {
title: {
display: true,
text: 'Age (Months)'
}
},
y: {
title: {
display: true,
text: 'Weight (kg)'
},
beginAtZero: false // Weight doesn't start 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;
}
}
},
legend: {
position: 'top',
}
},
// Add user data point later if desired, requires more complex dataset handling
}
});
}

function calculateGrowth() {
var ageValid = validateInput('ageMonths', 0, 12, 'ageMonthsError');
var weightValid = validateInput('weightKg', 0, null, 'weightKgError');
var lengthValid = validateInput('lengthCm', 0, null, 'lengthCmError');

if (!ageValid || !weightValid || !lengthValid) {
document.getElementById('primaryResult').textContent = 'Invalid Input';
document.getElementById('weightPercentile').textContent = '–';
document.getElementById('lengthPercentile').textContent = '–';
document.getElementById('bmiResult').textContent = '–';
return;
}

var age = parseFloat(document.getElementById('ageMonths').value);
var weight = parseFloat(document.getElementById('weightKg').value);
var length = parseFloat(document.getElementById('lengthCm').value);

var weightPercentile = getWeightPercentile(age, weight);
var lengthPercentile = getLengthPercentile(age, length);
var bmi = calculateBMI(weight, length);

var primaryResultText = 'Your baby boy is tracking ' + weightPercentile + ' for weight and ' + lengthPercentile + ' for length.';

document.getElementById('primaryResult').textContent = primaryResultText;
document.getElementById('weightPercentile').textContent = weightPercentile;
document.getElementById('lengthPercentile').textContent = lengthPercentile;
document.getElementById('bmiResult').textContent = isNaN(bmi) ? '–' : bmi.toFixed(2) + ' kg/m²';

// Update the chart
updateChart(age, weight, length);
}

function resetForm() {
document.getElementById('ageMonths').value = '6';
document.getElementById('weightKg').value = '7.9';
document.getElementById('lengthCm').value = '68.6';

// Clear error messages
document.getElementById('ageMonthsError').textContent = '';
document.getElementById('weightKgError').textContent = '';
document.getElementById('lengthCmError').textContent = '';

// Recalculate with default values
calculateGrowth();
}

function copyResults() {
var primaryResult = document.getElementById('primaryResult').innerText;
var weightPercentile = document.getElementById('weightPercentile').innerText;
var lengthPercentile = document.getElementById('lengthPercentile').innerText;
var bmi = document.getElementById('bmiResult').innerText;

var age = document.getElementById('ageMonths').value;
var weight = document.getElementById('weightKg').value;
var length = document.getElementById('lengthCm').value;

var assumptions = "Assumptions:\n- Age: " + age + " months\n- Weight: " + weight + " kg\n- Length: " + length + " cm";

var textToCopy = "Baby Boy Growth Analysis:\n\n" +
primaryResult + "\n" +
"Weight Percentile: " + weightPercentile + "\n" +
"Length Percentile: " + lengthPercentile + "\n" +
"BMI: " + bmi + "\n\n" +
assumptions;

navigator.clipboard.writeText(textToCopy).then(function() {
// Show confirmation temporarily
var copyButton = document.querySelector('.copy-btn');
var originalText = copyButton.innerText;
copyButton.innerText = 'Copied!';
setTimeout(function() {
copyButton.innerText = originalText;
}, 2000);
}).catch(function(err) {
console.error('Failed to copy: ', err);
// Fallback for older browsers or specific environments if needed
alert('Could not copy results. Please copy manually.');
});
}

// Initialize the calculator on page load
window.onload = function() {
// Add event listeners for real-time updates
var inputs = document.querySelectorAll('.loan-calc-container input');
for (var i = 0; i < inputs.length; i++) {
inputs[i].addEventListener('input', function() {
// Debounce or throttle if performance becomes an issue, but for this, direct call is usually fine.
calculateGrowth();
});
}

resetForm(); // Load default values and calculate

// Initialize canvas
var canvas = document.getElementById('growthChart');
if (canvas) {
var ctx = canvas.getContext('2d');
// Initialize chart with placeholder data or empty state if needed
myChart = new Chart(ctx, {
type: 'line',
data: {
labels: [],
datasets: []
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
x: { title: { display: true, text: 'Age (Months)' } },
y: { title: { display: true, text: 'Weight (kg)' }, beginAtZero: false }
},
plugins: { legend: { display: false } }
}
});
}
};

// Add FAQ toggling functionality
document.addEventListener('DOMContentLoaded', function() {
var faqQuestions = document.querySelectorAll('.faq-question');
for (var i = 0; i < faqQuestions.length; i++) {
faqQuestions[i].addEventListener('click', function() {
var faqItem = this.parentElement;
faqItem.classList.toggle('open');
var faqAnswer = faqItem.querySelector('.faq-answer');
if (faqItem.classList.contains('open')) {
faqAnswer.style.display = 'block';
} else {
faqAnswer.style.display = 'none';
}
});
}
});