Calculation Ideal Body Weight

Ideal Body Weight Calculator: Formulas & Examples :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –secondary-text-color: #666; –border-color: #ddd; –card-background: #fff; –shadow: 0 4px 8px rgba(0, 0, 0, 0.05); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: var(–background-color); color: var(–text-color); line-height: 1.6; margin: 0; padding: 0; } .container { max-width: 980px; margin: 20px auto; padding: 0 15px; display: flex; flex-direction: column; align-items: center; } header { background-color: var(–primary-color); color: white; padding: 20px 0; text-align: center; width: 100%; } header h1 { margin: 0; font-size: 2.5em; } main { width: 100%; background-color: var(–card-background); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-top: 20px; } h2, h3 { color: var(–primary-color); margin-top: 1.5em; margin-bottom: 0.5em; } .loan-calc-container { background-color: var(–card-background); padding: 25px; border-radius: 8px; box-shadow: var(–shadow); width: 100%; max-width: 600px; margin: 0 auto 30px auto; text-align: left; } .input-group { margin-bottom: 20px; display: flex; flex-direction: column; gap: 5px; } .input-group label { font-weight: bold; color: var(–secondary-text-color); display: block; } .input-group input[type="number"], .input-group select { width: calc(100% – 24px); padding: 12px; border: 1px solid var(–border-color); border-radius: 4px; font-size: 1em; box-sizing: border-box; } .input-group .helper-text { font-size: 0.85em; color: var(–secondary-text-color); } .error-message { color: red; font-size: 0.8em; margin-top: 5px; display: none; /* Hidden by default */ } .button-group { display: flex; gap: 10px; margin-top: 25px; justify-content: center; flex-wrap: wrap; } button { padding: 12px 25px; border: none; border-radius: 5px; font-size: 1em; font-weight: bold; cursor: pointer; transition: background-color 0.3s ease; min-width: 150px; } .btn-calculate { background-color: var(–primary-color); color: white; } .btn-calculate:hover { background-color: #003366; } .btn-reset { background-color: #6c757d; color: white; } .btn-reset:hover { background-color: #5a6268; } .btn-copy { background-color: #17a2b8; color: white; } .btn-copy:hover { background-color: #138496; } #results-container { margin-top: 30px; padding: 25px; border: 1px dashed var(–border-color); border-radius: 8px; background-color: #e9ecef; text-align: center; width: 100%; max-width: 600px; margin-left: auto; margin-right: auto; display: none; /* Hidden by default */ } #results-container.visible { display: block; } #primary-result { font-size: 2.8em; font-weight: bold; color: var(–success-color); margin-bottom: 10px; } .result-label { font-size: 1.1em; color: var(–secondary-text-color); margin-bottom: 5px; } .intermediate-results div { margin-top: 15px; font-size: 1.1em; } .intermediate-results span { font-weight: bold; color: var(–primary-color); } #formula-explanation { margin-top: 15px; font-size: 0.95em; color: var(–secondary-text-color); font-style: italic; } .chart-container { margin-top: 30px; padding: 25px; background-color: var(–card-background); border-radius: 8px; box-shadow: var(–shadow); width: 100%; max-width: 600px; margin: 30px auto; text-align: center; } .chart-container canvas { max-width: 100%; height: auto; } .chart-caption { font-size: 0.9em; color: var(–secondary-text-color); margin-top: 10px; } table { width: 100%; border-collapse: collapse; margin-top: 20px; box-shadow: var(–shadow); } th, td { padding: 12px 15px; text-align: left; border-bottom: 1px solid var(–border-color); } thead th { background-color: var(–primary-color); color: white; font-weight: bold; } tbody tr:nth-child(even) { background-color: #f2f2f2; } tbody tr:hover { background-color: #e9ecef; } caption { font-weight: bold; color: var(–primary-color); margin-bottom: 10px; text-align: left; font-size: 1.1em; } .article-content { width: 100%; background-color: var(–card-background); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-top: 20px; text-align: left; } .article-content h2 { border-bottom: 2px solid var(–primary-color); padding-bottom: 5px; margin-bottom: 15px; } .article-content h3 { margin-top: 20px; color: var(–primary-color); } .article-content p, .article-content ul, .article-content ol { margin-bottom: 15px; } .article-content ul li, .article-content ol li { margin-bottom: 8px; } .faq-item { margin-bottom: 15px; } .faq-item strong { color: var(–primary-color); display: block; margin-bottom: 5px; } .internal-links { margin-top: 30px; background-color: var(–card-background); padding: 25px; border-radius: 8px; box-shadow: var(–shadow); width: 100%; max-width: 600px; margin: 30px auto; } .internal-links h3 { text-align: center; color: var(–primary-color); margin-top: 0; } .internal-links ul { list-style: none; padding: 0; } .internal-links li { margin-bottom: 10px; border-bottom: 1px dashed var(–border-color); padding-bottom: 8px; } .internal-links li:last-child { border-bottom: none; } .internal-links a { color: var(–primary-color); text-decoration: none; font-weight: bold; } .internal-links a:hover { text-decoration: underline; } .internal-links span { font-size: 0.9em; color: var(–secondary-text-color); display: block; margin-top: 3px; } footer { text-align: center; padding: 20px; margin-top: 30px; font-size: 0.9em; color: var(–secondary-text-color); width: 100%; } @media (max-width: 768px) { .container { margin: 10px auto; padding: 0 10px; } .loan-calc-container, #results-container, .chart-container, .internal-links, .article-content { padding: 20px; } header h1 { font-size: 2em; } button { min-width: unset; width: 100%; } .button-group { flex-direction: column; align-items: center; } }

Ideal Body Weight Calculator

Calculate Your Ideal Body Weight

Enter your details below to find your ideal body weight range and related metrics.

Male Female Select your biological sex for the most accurate calculation.
Enter your height in centimeters.
Please enter a valid height (e.g., 120-250 cm).
You can also enter height in inches. If both are provided, cm will be used.
Please enter a valid height (e.g., 47-98 inches).
Medium Small Large Estimate your skeletal frame size.
Your Ideal Body Weight Range:
BMI Range:
Weight (kg):
Weight (lbs):
Ideal Body Weight Range vs. BMI for your Height

What is Ideal Body Weight?

The concept of ideal body weight (IBW) refers to the weight that is considered to be healthiest for a person based on their biological sex, height, and sometimes body frame size. It's not a single, rigid number but rather a healthy range that minimizes health risks associated with being significantly underweight or overweight. IBW serves as a valuable benchmark for assessing general health and identifying potential weight-related health concerns. It's important to note that IBW is a generalized guideline and doesn't account for individual variations like muscle mass, bone density, or specific medical conditions. Understanding your ideal body weight can be a first step towards achieving or maintaining a healthier lifestyle, but it should always be considered alongside overall well-being and professional medical advice.

Who should use it: Anyone interested in understanding their health status, individuals aiming for weight management (both loss and gain), healthcare professionals assessing patient health, and those seeking a personalized health goal. It's particularly useful for general health assessments, but not for athletes with significant muscle mass or individuals with certain medical conditions where specific weight targets are advised by a doctor.

Common misconceptions: A frequent misconception is that IBW is a strict target that must be hit precisely. In reality, it's a healthy range. Another myth is that IBW is solely determined by height; biological sex and body frame size also play crucial roles. Lastly, some believe that IBW calculators can diagnose health problems, which they cannot; they are merely tools for estimation and health awareness.

Ideal Body Weight Formula and Mathematical Explanation

Calculating the ideal body weight involves several formulas, often tailored to biological sex. One of the most commonly used methods for adults is the Devine formula, though others like the Robinson and Miller formulas exist. We will use a simplified approach based on common guidelines often derived from these formulas, adjusted for frame size.

Simplified Adult Ideal Body Weight Calculation (using height in cm):

This calculation uses a baseline weight for a medium frame and adjusts for biological sex, height, and frame size. The base weight for a medium frame is often considered around 45.5 kg for women and 48 kg for men at 150 cm height.

  • For Females:
  • Base Weight (150 cm, Medium Frame): 45.5 kg
  • Additional Weight per cm over 150 cm: 0.9 kg
  • Frame Adjustment: -3 kg (Small Frame), 0 kg (Medium Frame), +3 kg (Large Frame)
  • Formula (approximate for Females):
  • IBW (kg) = 45.5 + (Height_cm – 150) * 0.9 + Frame_Adjustment_Female
  • (Where Frame_Adjustment_Female is -3 for Small, 0 for Medium, +3 for Large)
  • For Males:
  • Base Weight (150 cm, Medium Frame): 48 kg
  • Additional Weight per cm over 150 cm: 1.1 kg
  • Frame Adjustment: -3 kg (Small Frame), 0 kg (Medium Frame), +3 kg (Large Frame)
  • Formula (approximate for Males):
  • IBW (kg) = 48 + (Height_cm – 150) * 1.1 + Frame_Adjustment_Male
  • (Where Frame_Adjustment_Male is -3 for Small, 0 for Medium, +3 for Large)

Note: The formula provides a target weight. A healthy range is typically considered +/- 10% of this target. We also calculate the BMI associated with this target weight to provide context.

A healthy BMI range is generally considered to be between 18.5 and 24.9. The calculator uses this to estimate a weight range corresponding to a healthy BMI for the given height.

Variables Table:

Variables Used in Ideal Body Weight Calculation
Variable Meaning Unit Typical Range
Height The vertical distance from the sole of the foot to the top of the head. cm (or inches) 120 – 250 cm (47 – 98 inches)
Biological Sex Differentiates physiological characteristics typically associated with male or female development. Category (Male/Female) Male, Female
Body Frame Size An estimation of the size of a person's skeletal structure. Category (Small/Medium/Large) Small, Medium, Large
Ideal Body Weight (IBW) The weight range considered most healthy for an individual based on their attributes. kg (or lbs) Varies significantly by height and sex
Body Mass Index (BMI) A measure of body fat based on height and weight. kg/m² 18.5 – 24.9 (Healthy Range)

Practical Examples (Real-World Use Cases)

Understanding how the ideal body weight calculator works can be clarified with practical examples. These scenarios illustrate how different inputs yield varied results, emphasizing the personalization of health metrics.

Example 1: A Young Woman Seeking Weight Goals

Scenario: Sarah is a 25-year-old woman who is 165 cm tall and believes she has a medium body frame. She wants to understand her ideal body weight to set realistic fitness goals.

Inputs:

  • Biological Sex: Female
  • Height: 165 cm
  • Body Frame Size: Medium

Calculation Process (Simplified):

  • Base Weight (Female, 150cm, Medium): 45.5 kg
  • Height Adjustment: (165 cm – 150 cm) * 0.9 kg/cm = 15 cm * 0.9 kg/cm = 13.5 kg
  • Frame Adjustment (Medium): 0 kg
  • Target IBW (kg): 45.5 kg + 13.5 kg + 0 kg = 59 kg
  • Target IBW (lbs): 59 kg * 2.20462 = ~130 lbs
  • Lower end of range (10% less): 59 kg * 0.9 = ~53.1 kg
  • Upper end of range (10% more): 59 kg * 1.1 = ~64.9 kg
  • Healthy BMI range for 165cm height:
  • Lower weight for BMI 18.5: 18.5 * (1.65^2) = ~50.4 kg
  • Upper weight for BMI 24.9: 24.9 * (1.65^2) = ~67.7 kg

Results:

  • Ideal Body Weight Range: Approximately 53.1 kg to 64.9 kg (117 lbs to 143 lbs)
  • Target Weight: 59 kg (130 lbs)
  • Associated BMI: ~21.7 (within the healthy 18.5-24.9 range)

Interpretation: Sarah's ideal body weight falls between 53.1 kg and 64.9 kg. Her target weight of 59 kg aligns with a healthy BMI. This gives her a clear, achievable range to aim for in her fitness and nutrition journey.

Example 2: A Man Assessing His Weight After a Growth Spurt

Scenario: David is a 19-year-old man who is 188 cm tall. He feels he might be carrying a bit too much weight and wants to see where he stands. He estimates his body frame as large.

Inputs:

  • Biological Sex: Male
  • Height: 188 cm
  • Body Frame Size: Large

Calculation Process (Simplified):

  • Base Weight (Male, 150cm, Medium): 48 kg
  • Height Adjustment: (188 cm – 150 cm) * 1.1 kg/cm = 38 cm * 1.1 kg/cm = 41.8 kg
  • Frame Adjustment (Large): +3 kg
  • Target IBW (kg): 48 kg + 41.8 kg + 3 kg = 92.8 kg
  • Target IBW (lbs): 92.8 kg * 2.20462 = ~204.6 lbs
  • Lower end of range (10% less): 92.8 kg * 0.9 = ~83.5 kg
  • Upper end of range (10% more): 92.8 kg * 1.1 = ~102.1 kg
  • Healthy BMI range for 188cm height:
  • Lower weight for BMI 18.5: 18.5 * (1.88^2) = ~65.2 kg
  • Upper weight for BMI 24.9: 24.9 * (1.88^2) = ~87.7 kg

Results:

  • Ideal Body Weight Range: Approximately 83.5 kg to 102.1 kg (184 lbs to 225 lbs)
  • Target Weight: 92.8 kg (204.6 lbs)
  • Associated BMI: ~26.2 (Slightly above the healthy 18.5-24.9 range)

Interpretation: David's calculated ideal body weight range is 83.5 kg to 102.1 kg. His current target weight of 92.8 kg falls slightly above the standard healthy BMI range (which caps out around 87.7 kg for his height). This suggests that while he is within his calculated IBW range, he might be on the higher end. For David, focusing on healthy habits and potentially losing a few kilograms could bring him more squarely into the optimal health zone, especially considering the BMI context.

How to Use This Ideal Body Weight Calculator

Using our ideal body weight calculator is straightforward and designed for clarity. Follow these steps to get your personalized results:

  1. Enter Height: Input your height accurately in either centimeters (preferred) or inches. If you provide both, the calculator will prioritize centimeters. Ensure the value is within the typical adult height range.
  2. Select Biological Sex: Choose 'Male' or 'Female' from the dropdown menu. This selection is crucial as physiological differences impact ideal weight calculations.
  3. Choose Body Frame Size: Estimate your body frame size as Small, Medium, or Large. A common way to estimate this is by looking at your wrist circumference relative to your height or by observing your natural build.
  4. Click 'Calculate': Once all fields are populated correctly, click the 'Calculate' button.
  5. Review Results: The calculator will display your ideal body weight range, a target weight, and the corresponding BMI range. It will also show intermediate values used in the calculation.
  6. Understand the Formula: A brief explanation of the formula used is provided for transparency.
  7. Visualize with Chart: The dynamic chart illustrates your calculated ideal body weight range against the broader BMI categories for your height, offering a visual context.
  8. Reset or Copy: Use the 'Reset' button to clear the fields and start over. The 'Copy Results' button allows you to save or share your calculated data.

How to read results: The primary result shows your ideal body weight range. Aiming for a weight within this range is generally associated with better health outcomes. The target weight is the midpoint of this range. The associated BMI provides a standardized measure of weight relative to height.

Decision-making guidance: If your current weight falls outside the calculated range, consider consulting a healthcare professional. They can provide personalized advice based on your specific health status, body composition (muscle vs. fat), and lifestyle. Remember that IBW is a guideline, not a definitive medical diagnosis.

Key Factors That Affect Ideal Body Weight Results

While the ideal body weight calculator provides a valuable estimate, several factors can influence the interpretation and application of these results. Understanding these elements ensures a more holistic approach to health and weight management.

  1. Muscle Mass: Individuals with higher muscle mass, such as athletes or those who engage in regular strength training, may weigh more than their IBW suggests, even if they have low body fat. Muscle is denser than fat, leading to a higher scale weight. Our calculator doesn't directly measure muscle mass, so a very muscular person might appear "overweight" by IBW standards when they are actually very fit.
  2. Bone Density: Similarly, people with naturally larger or denser bone structures might weigh more than predicted by standard IBW formulas. This is an inherent physiological difference that calculators typically don't account for.
  3. Age: Body composition and metabolism change with age. Older adults may naturally have less muscle mass and potentially a slightly different ideal weight range compared to younger individuals, though standard formulas often don't differentiate significantly by age beyond adulthood.
  4. Genetics: Genetic predisposition plays a role in body shape, metabolism, and fat distribution. Some individuals are genetically inclined to be leaner or carry more weight, regardless of lifestyle choices.
  5. Body Fat Percentage: IBW and BMI don't directly measure body fat percentage. Two people with the same height and weight can have vastly different health profiles based on their body fat content. A focus on achieving a healthy body fat percentage is often more beneficial than solely chasing a number on the scale.
  6. Medical Conditions: Certain health conditions (e.g., hormonal imbalances, edema, specific diseases) can affect body weight and fluid retention, making standard IBW calculations less relevant. Always consult a doctor if you have a medical condition.
  7. Ethnicity: Research suggests that certain health risks associated with weight may vary across different ethnic groups, even at the same BMI. For instance, some Asian populations may experience health issues at lower BMIs than Caucasian populations.
  8. Pregnancy and Postpartum: Weight gain during pregnancy is essential, and postpartum recovery involves gradual weight loss. IBW calculations are not applicable during these periods.

Frequently Asked Questions (FAQ)

Q: What is the difference between Ideal Body Weight (IBW) and Body Mass Index (BMI)?

A: IBW is a calculation of a target weight range based on height, sex, and frame size, aiming for a healthy weight. BMI is a ratio of weight to height squared (kg/m²), providing a broader classification of weight status (underweight, normal, overweight, obese). Our calculator provides both IBW and the corresponding BMI range for context.

Q: Are there different formulas for calculating Ideal Body Weight?

A: Yes, several formulas exist, such as the Devine, Robinson, Miller, and Hamwi formulas. They often yield slightly different results. The approach used here is a common approximation that considers height, sex, and frame size to provide a general guideline.

Q: Can children use this Ideal Body Weight calculator?

A: This calculator is designed primarily for adults. Children are still growing and developing, so their weight needs are different. Pediatric growth charts and professional medical advice are essential for assessing a child's weight.

Q: My calculated IBW seems low. Am I unhealthy?

A: Not necessarily. IBW is a guideline. If you are muscular or have a larger frame, your weight might naturally be higher than the calculated IBW. Consider your overall health, energy levels, and body composition. Consulting a healthcare provider is the best way to assess your health status accurately.

Q: How accurate are IBW calculators?

A: IBW calculators provide estimates and are not definitive diagnoses. They don't account for individual variations like muscle mass, body fat percentage, or bone density. They serve as a useful starting point for understanding healthy weight goals.

Q: Should I prioritize reaching my IBW exactly?

A: No, it's best to aim for the calculated ideal body weight range. Health exists across a spectrum, and focusing on a narrow target can be counterproductive. Consistency with healthy eating and exercise is more important than hitting an exact number.

Q: How does body frame size affect IBW?

A: Body frame size adjusts the IBW up or down slightly. Individuals with smaller frames tend to have lower IBWs, while those with larger frames may have higher IBWs, assuming similar height and sex. This accounts for skeletal differences.

Q: What are the limitations of using IBW for health assessment?

A: The main limitation is that IBW doesn't differentiate between fat mass and lean mass (muscle, bone). A very muscular person could be classified as overweight by IBW/BMI standards, which is inaccurate for their health status. It's a simplified metric.

© 2023 Your Website Name. All rights reserved.

function validateInput(id, min, max, errorId) { var input = document.getElementById(id); var errorElement = document.getElementById(errorId); var value = parseFloat(input.value); if (isNaN(value) || value max) { errorElement.style.display = 'block'; input.style.borderColor = 'red'; return false; } else { errorElement.style.display = 'none'; input.style.borderColor = 'var(–border-color)'; return true; } } function validateAndCalculate() { var isValidHeightCm = validateInput('heightCm', 120, 250, 'heightCmError'); var isValidHeightInches = validateInput('heightInches', 47, 98, 'heightInchesError'); var isHeightCmProvided = document.getElementById('heightCm').value !== "; var isHeightInchesProvided = document.getElementById('heightInches').value !== "; if ((isHeightCmProvided && isValidHeightCm) || (isHeightInchesProvided && isValidHeightInches) || (!isHeightCmProvided && !isHeightInchesProvided)) { if (isHeightCmProvided && isValidHeightCm) { document.getElementById('heightInches').value = "; // Clear inches if cm is valid document.getElementById('heightInchesError').style.display = 'none'; document.getElementById('heightInches').style.borderColor = 'var(–border-color)'; } else if (isHeightInchesProvided && isValidHeightInches) { document.getElementById('heightCm').value = "; // Clear cm if inches is valid document.getElementById('heightCmError').style.display = 'none'; document.getElementById('heightCm').style.borderColor = 'var(–border-color)'; } calculateIdealBodyWeight(); } else { document.getElementById('results-container').classList.remove('visible'); } } function calculateIdealBodyWeight() { var gender = document.getElementById('gender').value; var heightCmInput = document.getElementById('heightCm'); var heightInchesInput = document.getElementById('heightInches'); var frameSize = document.getElementById('frameSize').value; var heightCm = 0; var heightInches = 0; if (heightCmInput.value) { heightCm = parseFloat(heightCmInput.value); } if (heightInchesInput.value) { heightInches = parseFloat(heightInchesInput.value); } var inputValid = false; if (heightCm > 0 && heightCm >= 120 && heightCm 0 && heightInches >= 47 && heightInches <= 98) { heightCm = heightInches * 2.54; // Convert inches to cm inputValid = true; } if (!inputValid) { document.getElementById('results-container').classList.remove('visible'); return; } var baseWeightFemale = 45.5; // kg for 150 cm medium frame var heightIncrementFemale = 0.9; // kg per cm over 150 cm var baseWeightMale = 48.0; // kg for 150 cm medium frame var heightIncrementMale = 1.1; // kg per cm over 150 cm var frameAdjustment = 0; if (frameSize === 'small') { frameAdjustment = -3; } else if (frameSize === 'large') { frameAdjustment = 3; } var targetWeightKg; if (gender === 'female') { targetWeightKg = baseWeightFemale + (heightCm – 150) * heightIncrementFemale + frameAdjustment; } else { // male targetWeightKg = baseWeightMale + (heightCm – 150) * heightIncrementMale + frameAdjustment; } // Ensure target weight is not negative (edge case for very short heights) if (targetWeightKg < 0) { targetWeightKg = 0; } var targetWeightLbs = targetWeightKg * 2.20462; // Calculate a healthy range, typically +/- 10% of target weight var lowerWeightKg = targetWeightKg * 0.9; var upperWeightKg = targetWeightKg * 1.1; var lowerWeightLbs = targetWeightKg * 0.9 * 2.20462; var upperWeightLbs = targetWeightKg * 1.1 * 2.20462; // Also calculate range based on healthy BMI (18.5 to 24.9) var heightM = heightCm / 100; var bmiLowerBoundKg = 18.5 * (heightM * heightM); var bmiUpperBoundKg = 24.9 * (heightM * heightM); // Use the wider of the two ranges (IBW +/- 10% or BMI range) var finalLowerWeightKg = Math.max(lowerWeightKg, bmiLowerBoundKg); var finalUpperWeightKg = Math.min(upperWeightKg, bmiUpperBoundKg); var finalLowerWeightLbs = finalLowerWeightKg * 2.20462; var finalUpperWeightLbs = finalUpperWeightKg * 2.20462; // Recalculate target weight based on the adjusted range midpoint if needed, or keep original // For simplicity, we'll keep the original calculated target weight and show the derived range var finalTargetWeightKg = targetWeightKg; // Original target var finalTargetWeightLbs = targetWeightKg * 2.20462; // Display Results document.getElementById('primary-result').innerText = finalLowerWeightKg.toFixed(1) + ' – ' + finalUpperWeightKg.toFixed(1) + ' kg'; document.getElementById('weightKg').getElementsByTagName('span')[0].innerText = finalLowerWeightKg.toFixed(1) + ' – ' + finalUpperWeightKg.toFixed(1) + ' kg'; document.getElementById('weightLbs').getElementsByTagName('span')[0].innerText = finalLowerWeightLbs.toFixed(1) + ' – ' + finalUpperWeightLbs.toFixed(1) + ' lbs'; var averageBmi = ((18.5 + 24.9) / 2); var bmiForTargetWeight = finalTargetWeightKg / (heightM * heightM); document.getElementById('bmiRange').getElementsByTagName('span')[0].innerText = bmiForTargetWeight.toFixed(1) + ' (Healthy Range: 18.5 – 24.9)'; var formulaText = "Using a formula adjusted for height, biological sex, and body frame size. "; formulaText += "The healthy weight range is typically considered +/- 10% of the target weight, "; formulaText += "and also within the healthy BMI range (18.5-24.9 kg/m²)."; document.getElementById('formula-explanation').innerText = formulaText; document.getElementById('results-container').classList.add('visible'); updateChart(heightCm, finalLowerWeightKg, finalUpperWeightKg, bmiLowerBoundKg, bmiUpperBoundKg, gender, frameSize); } function resetCalculator() { document.getElementById('gender').value = 'male'; document.getElementById('heightCm').value = ''; document.getElementById('heightInches').value = ''; document.getElementById('frameSize').value = 'medium'; document.getElementById('results-container').classList.remove('visible'); document.getElementById('heightCmError').style.display = 'none'; document.getElementById('heightInchesError').style.display = 'none'; document.getElementById('heightCm').style.borderColor = 'var(–border-color)'; document.getElementById('heightInches').style.borderColor = 'var(–border-color)'; clearChart(); } function copyResults() { var resultText = "Ideal Body Weight Calculation Results:\n\n"; resultText += "Primary Result (Ideal Weight Range): " + document.getElementById('primary-result').innerText + "\n"; resultText += "Weight Range (kg): " + document.getElementById('weightKg').getElementsByTagName('span')[0].innerText + "\n"; resultText += "Weight Range (lbs): " + document.getElementById('weightLbs').getElementsByTagName('span')[0].innerText + "\n"; resultText += "Associated BMI: " + document.getElementById('bmiRange').getElementsByTagName('span')[0].innerText + "\n"; resultText += "Formula Used: " + document.getElementById('formula-explanation').innerText + "\n\n"; resultText += "Assumptions:\n"; resultText += "- Biological Sex: " + document.getElementById('gender').value.charAt(0).toUpperCase() + document.getElementById('gender').value.slice(1) + "\n"; resultText += "- Height: " + (document.getElementById('heightCm').value ? document.getElementById('heightCm').value + ' cm' : document.getElementById('heightInches').value + ' inches') + "\n"; resultText += "- Body Frame Size: " + document.getElementById('frameSize').value.charAt(0).toUpperCase() + document.getElementById('frameSize').value.slice(1) + "\n"; var textArea = document.createElement("textarea"); textArea.value = resultText; document.body.appendChild(textArea); textArea.select(); try { document.execCommand('copy'); alert('Results copied to clipboard!'); } catch (e) { alert('Failed to copy results. Please copy manually.'); } document.body.removeChild(textArea); } var myChart; var chartCanvas = document.getElementById('weightChart').getContext('2d'); function updateChart(heightCm = 170, ibwLowerKg = 55, ibwUpperKg = 65, bmiLowerKg = 50, bmiUpperKg = 70, gender = 'female', frameSize = 'medium') { if (myChart) { myChart.destroy(); } var heightM = heightCm / 100; var chartHeightData = []; var bmiLabels = []; var chartMaxHeight = 250; // Max height for chart axis var step = 5; // cm step for (var h = 120; h <= chartMaxHeight; h += step) { var hM = h / 100; var baseWeightF = 45.5; var incF = 0.9; var baseWeightM = 48.0; var incM = 1.1; var frameAdj = 0; if (frameSize === 'small') frameAdj = -3; if (frameSize === 'large') frameAdj = 3; var targetW; if (gender === 'female') { targetW = baseWeightF + (h – 150) * incF + frameAdj; } else { targetW = baseWeightM + (h – 150) * incM + frameAdj; } if (targetW item.height); var datasetIdealLower = chartHeightData.map(item => item.idealWeightLower); var datasetIdealUpper = chartHeightData.map(item => item.idealWeightUpper); var datasetBmiLower = chartHeightData.map(item => item.bmiWeightLower); var datasetBmiUpper = chartHeightData.map(item => item.bmiWeightUpper); var currentHeightValue = parseFloat(document.getElementById('heightCm').value) || (parseFloat(document.getElementById('heightInches').value) * 2.54 || 170); if (currentHeightValue chartMaxHeight) currentHeightValue = chartMaxHeight; myChart = new Chart(chartCanvas, { type: 'line', data: { labels: labels, datasets: [ { label: 'Ideal Weight Range', data: datasetIdealLower.map((val, i) => ({ x: labels[i], y: val })), borderColor: 'var(–success-color)', backgroundColor: 'rgba(40, 167, 69, 0.2)', fill: '+1', // Fill between this dataset and the next one tension: 0.2, pointRadius: 0 }, { label: ' ', // This dataset is just for filling the area data: datasetIdealUpper.map((val, i) => ({ x: labels[i], y: val })), borderColor: 'transparent', backgroundColor: 'transparent', fill: '-1', // Fill between this dataset and the previous one tension: 0.2, pointRadius: 0 }, { label: 'Healthy BMI Range', data: datasetBmiLower.map((val, i) => ({ x: labels[i], y: val })), borderColor: 'rgba(0, 0, 0, 0.1)', backgroundColor: 'rgba(0, 0, 0, 0.05)', fill: '+1', tension: 0.2, pointRadius: 0, borderDash: [5, 5] }, { label: ' ', // Fill for BMI range data: datasetBmiUpper.map((val, i) => ({ x: labels[i], y: val })), borderColor: 'transparent', backgroundColor: 'transparent', fill: '-1', tension: 0.2, pointRadius: 0 }, // Vertical line for current height { label: 'Your Height', data: [ { x: currentHeightValue, y: 0 }, { x: currentHeightValue, y: 150 } // Extend line to a reasonable max weight ], borderColor: 'var(–primary-color)', borderWidth: 2, borderDash: [8, 4], pointRadius: 5, pointBackgroundColor: 'var(–primary-color)', type: 'line', // Force as line to draw vertical segment showLine: true } ] }, options: { responsive: true, maintainAspectRatio: true, aspectRatio: 1.5, // Adjust for better aspect ratio plugins: { title: { display: true, text: 'Weight Ranges by Height', font: { size: 16 } }, legend: { display: true, position: 'top', }, tooltip: { enabled: true, callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.y !== undefined) { label += context.parsed.y.toFixed(1) + ' kg'; } return label; } } } }, scales: { x: { title: { display: true, text: 'Height (cm)' }, min: 120, max: chartMaxHeight, ticks: { stepSize: 20 } }, y: { title: { display: true, text: 'Weight (kg)' }, beginAtZero: true, min: 0, max: 150 // Max weight for y-axis } } } }); } function clearChart() { if (myChart) { myChart.destroy(); } // Clear canvas context if needed, though destroy should suffice chartCanvas.clearRect(0, 0, chartCanvas.canvas.width, chartCanvas.canvas.height); } // Initial call to set up default chart or update after load document.addEventListener('DOMContentLoaded', function() { updateChart(); // Load initial chart with default values validateAndCalculate(); // Trigger initial validation and calculation if inputs have defaults });

Leave a Comment