How to Calculate Goal Weight

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How to Calculate Your Goal Weight

This comprehensive guide and calculator help you determine a healthy and realistic goal weight based on scientific principles like BMI and Basal Metabolic Rate.

Goal Weight Calculator

Enter your current details and preferences to estimate your target weight range.

Enter your current weight in kilograms (kg).
Enter your height in centimeters (cm).
Sedentary (little or no exercise) Lightly active (exercise 1-3 days/week) Moderately active (exercise 3-5 days/week) Very active (hard exercise 6-7 days/week) Extra active (very hard exercise & physical job) Choose the option that best describes your daily physical activity.
Lose Weight Maintain Weight Gain Weight Select your desired weight change outcome.
Enter the desired weekly change in kilograms (e.g., 0.5 for 0.5 kg loss/week, -0.5 for 0.5 kg gain/week). Use 0 for maintenance.

Your Estimated Goal Weight

BMI Range:
BMR (Kcal/day):
TDEE (Kcal/day):
Calculations based on BMI classifications and TDEE estimates. Goal weight is derived by adjusting TDEE to achieve target weekly change.
Projected Weight Over Time
Healthy Weight Ranges Based on BMI
BMI Category BMI Range Weight Range (kg)

What is Goal Weight?

{primary_keyword} is the specific body weight that an individual aims to achieve and maintain for optimal health and well-being. It's not just a number on the scale; it's a weight that aligns with a healthy body composition, supports bodily functions, reduces the risk of chronic diseases, and allows for a good quality of life. Understanding how to calculate your goal weight is a crucial step in any weight management journey, whether you are aiming to lose, gain, or maintain your current weight.

This calculation is essential for anyone looking to set realistic and achievable targets. It's particularly useful for individuals who are:

  • Starting a weight loss or weight gain program.
  • Seeking to understand what a healthy weight looks like for their body.
  • Reaching a plateau in their current weight management efforts.
  • Recovering from illness or surgery and need to regain strength.

A common misconception about goal weight is that it should be a single, precise number. In reality, a healthy weight exists within a range. Another misconception is that everyone with the same height should aim for the same goal weight, ignoring individual factors like body composition, muscle mass, and bone density. This guide aims to clarify these points and provide a robust method for determining your personalized goal weight range.

{primary_keyword} Formula and Mathematical Explanation

Calculating a {primary_keyword} involves several interconnected steps, primarily relying on Body Mass Index (BMI) and Total Daily Energy Expenditure (TDEE). Here's a breakdown of the formulas and variables involved:

1. Body Mass Index (BMI) Calculation

BMI is a widely used screening tool to categorize a person's weight status relative to their height. It's calculated as:

BMI = (Weight in kilograms) / (Height in meters)²

2. Establishing Healthy BMI Categories

The World Health Organization (WHO) defines standard BMI categories:

  • Underweight: BMI < 18.5
  • Normal weight: 18.5 – 24.9
  • Overweight: 25 – 29.9
  • Obesity Class I: 30 – 34.9
  • Obesity Class II: 35 – 39.9
  • Obesity Class III: BMI ≥ 40

For {primary_keyword} calculations, we typically aim for the 'Normal weight' range (18.5-24.9).

3. Basal Metabolic Rate (BMR) Calculation

BMR is the number of calories your body burns at rest to maintain basic functions. The Mifflin-St Jeor equation is commonly used:

For men: BMR = (10 × Weight in kg) + (6.25 × Height in cm) - (5 × Age) + 5

For women: BMR = (10 × Weight in kg) + (6.25 × Height in cm) - (5 × Age) - 161

*(Note: For simplicity in this calculator, we omit age, as it's not provided as an input, focusing on weight and height. A more precise calculation would include age.)*

4. Total Daily Energy Expenditure (TDEE) Calculation

TDEE accounts for your BMR plus the calories burned through physical activity. It's calculated by multiplying BMR by an activity factor:

TDEE = BMR × Activity Factor

The Activity Factor ranges are provided in the calculator's dropdown menu.

5. Calculating Goal Weight based on Target Change

To determine a {primary_keyword}, we often work backward from the TDEE, considering the target weekly weight change. A deficit of approximately 3500 calories is needed to lose 0.45 kg (1 lb) of fat. Therefore, to lose or gain 1 kg per week, a difference of about 7700 calories per week is required. This translates to a daily caloric adjustment.

Daily Calorie Adjustment = Target Weekly Weight Change (kg) × 7700 kcal/kg

Target Daily Calorie Intake = TDEE - Daily Calorie Adjustment

The goal weight is then estimated based on achieving this target daily calorie intake, assuming the same metabolic rate at the goal weight (this is an approximation; actual metabolism might slightly change).

A simpler approach used by the calculator is to identify a target weight within the healthy BMI range (e.g., targeting the midpoint or a specific BMI value like 22) that aligns with your height.

Variables Used:

Variable Meaning Unit Typical Range / Values
Current Weight Your present body mass. Kilograms (kg) > 0
Height Your standing height. Centimeters (cm) > 0
Activity Factor Multiplier reflecting daily physical activity. Decimal (e.g., 1.2 – 1.9) 1.2 to 1.9
Weight Goal Desired outcome: Lose, Maintain, Gain. Categorical Lose, Maintain, Gain
Target Weekly Weight Change Desired rate of weight change per week. Kilograms (kg) e.g., -1.0 to 1.0 (0 for maintenance)
BMI Body Mass Index. kg/m² Calculated (typically 18.5 – 24.9 for healthy)
BMR Basal Metabolic Rate. Kilocalories (kcal) / day Calculated
TDEE Total Daily Energy Expenditure. Kilocalories (kcal) / day Calculated

Practical Examples (Real-World Use Cases)

Example 1: Weight Loss Goal

Scenario: Sarah is 30 years old, weighs 80 kg, and is 165 cm tall. She leads a moderately active lifestyle (exercises 3-5 days/week) and wants to lose weight. She aims for a safe and sustainable weight loss of 0.5 kg per week.

Inputs for Calculator:

  • Current Weight: 80 kg
  • Height: 165 cm
  • Activity Level: Moderately active (1.55)
  • Weight Goal: Lose Weight
  • Target Weekly Weight Change: 0.5 kg

Estimated Results:

  • Current BMI: Approx. 29.4 (Overweight)
  • BMR: Approx. 1465 kcal/day
  • TDEE: Approx. 2271 kcal/day
  • Estimated Goal Weight Range: 56 kg – 75 kg (Targeting BMI 21-24.9)
  • Suggested Daily Calorie Intake for Goal: ~1771 kcal/day (to achieve 0.5kg loss/week)

Interpretation: Sarah's current BMI falls into the overweight category. The calculator suggests a goal weight range for her height that falls within the healthy BMI zone. To achieve her goal of losing 0.5 kg per week, she would need to consume approximately 1771 calories daily, coupled with her moderate activity level. Her calculated goal weight might be around 65kg, a target that aligns with a healthy BMI of ~23.9.

Example 2: Weight Gain Goal

Scenario: David is 25 years old, weighs 60 kg, and is 180 cm tall. He has a sedentary job but goes to the gym 3 times a week. He wants to gain muscle and reach a healthier weight.

Inputs for Calculator:

  • Current Weight: 60 kg
  • Height: 180 cm
  • Activity Level: Lightly active (1.375) – *assuming gym sessions count as light activity*
  • Weight Goal: Gain Weight
  • Target Weekly Weight Change: 0.25 kg (for lean muscle gain)

Estimated Results:

  • Current BMI: Approx. 18.5 (Lower end of Normal weight)
  • BMR: Approx. 1575 kcal/day
  • TDEE: Approx. 2166 kcal/day
  • Estimated Goal Weight Range: 65 kg – 81 kg (Targeting BMI 20-25)
  • Suggested Daily Calorie Intake for Goal: ~2366 kcal/day (to achieve 0.25kg gain/week)

Interpretation: David's current BMI is at the lower end of the healthy range. The calculator indicates that a goal weight aiming for a slightly higher BMI within the normal range would be beneficial. To achieve a lean muscle gain of 0.25 kg per week, he would need to consume around 2366 calories daily. His goal weight might be set around 72kg, corresponding to a BMI of ~22.2, which is ideal for muscle building and overall health.

How to Use This {primary_keyword} Calculator

Using this calculator is straightforward. Follow these steps to get your personalized goal weight estimate:

  1. Enter Current Weight: Input your current body weight in kilograms (kg).
  2. Enter Height: Input your height in centimeters (cm).
  3. Select Activity Level: Choose the option that best reflects your typical daily physical activity. This is crucial for accurately estimating your calorie needs.
  4. Define Weight Goal: Select whether you aim to 'Lose Weight', 'Maintain Weight', or 'Gain Weight'.
  5. Set Target Weekly Change: For weight loss, enter a positive number (e.g., 0.5 for 0.5 kg/week). For weight gain, enter a negative number (e.g., -0.25 for 0.25 kg/week). Enter 0 if your goal is maintenance.
  6. Click 'Calculate Goal Weight': The calculator will process your inputs.

Reading the Results:

  • Estimated Goal Weight Range: This shows a spectrum of weights considered healthy for your height, typically within the normal BMI range (18.5-24.9). It's important to aim for a weight within this range.
  • BMI Range: Displays the corresponding BMI values for the healthy weight range.
  • BMR (Kcal/day): Your estimated Basal Metabolic Rate – calories burned at rest.
  • TDEE (Kcal/day): Your estimated Total Daily Energy Expenditure – total calories burned daily including activity.
  • Suggested Daily Calorie Intake: Based on your goal (lose/gain/maintain) and target weekly change, this is the approximate daily calorie intake needed.

Decision-Making Guidance:

Use the results as a guide, not a rigid prescription. Your {primary_keyword} should be a weight where you feel healthy, energetic, and capable of sustaining a balanced lifestyle. Consult with a healthcare professional or registered dietitian to tailor a plan that suits your individual needs, health status, and preferences. Remember that sustainable progress is key, and focusing on overall health markers beyond just weight is important.

Key Factors That Affect {primary_keyword} Results

While the calculator provides a good estimate, several factors can influence your actual {primary_keyword} and the journey to reach it. Understanding these nuances helps in setting realistic expectations and adjusting your approach:

  1. Body Composition: Muscle is denser than fat. Two people with the same height and BMI can have very different body compositions and health outcomes. Someone with higher muscle mass might weigh more but be healthier than someone with lower muscle mass and higher body fat percentage. Your goal weight might need adjustment based on your desired muscle tone and fat percentage.
  2. Age: Metabolism tends to slow down with age. Older adults may require fewer calories to maintain their weight compared to younger individuals. While this calculator doesn't explicitly use age, it's a factor to consider when fine-tuning your calorie intake. For more precise calculations, check out our BMR Calculator.
  3. Genetics: Individual genetic predispositions can influence metabolism, fat distribution, and the ease with which one gains or loses weight. Some individuals may find it naturally easier to maintain a certain weight than others.
  4. Hormonal Balance: Hormones play a significant role in appetite regulation, metabolism, and fat storage. Conditions like thyroid issues, PCOS, or insulin resistance can significantly impact weight and may require specific medical management rather than relying solely on calorie calculations.
  5. Dietary Habits Beyond Calories: The quality of your diet matters immensely. Focusing on nutrient-dense whole foods, adequate protein intake, fiber, and hydration supports overall health, satiety, and metabolic function, aiding weight management more effectively than simply tracking calories. Consider exploring our resources on Healthy Eating Principles.
  6. Medical Conditions and Medications: Certain health conditions (e.g., diabetes, heart disease) and medications (e.g., corticosteroids, antidepressants) can affect weight. It's crucial to discuss weight goals with your doctor if you have any underlying health concerns.
  7. Lifestyle Factors: Sleep quality, stress levels, and consistent physical activity are critical. Chronic stress can lead to hormonal imbalances that promote weight gain, while poor sleep can disrupt appetite-regulating hormones. Consistent exercise supports TDEE and body composition.
  8. Metabolic Adaptation: As you lose weight, your metabolism may slow down slightly (adaptive thermogenesis). This means you might need to adjust your calorie intake further or increase activity to continue losing weight, especially if you aim for significant loss. Similarly, gaining weight might slightly increase BMR.

Frequently Asked Questions (FAQ)

What is the ideal BMI for my goal weight?

The generally accepted ideal BMI range for adults is 18.5 to 24.9, often referred to as the 'normal' or 'healthy' weight category. This calculator uses this range to determine your goal weight range.

Is BMI a perfect measure of health?

No, BMI is a screening tool and has limitations. It doesn't distinguish between muscle mass and fat mass, nor does it account for body composition, bone density, or fat distribution. However, it's a useful initial indicator for population health and provides a basis for {primary_keyword} estimation.

How quickly should I aim to reach my goal weight?

A sustainable and healthy rate of weight loss is typically 0.5 to 1 kg (1 to 2 lbs) per week. For weight gain, a rate of 0.25 to 0.5 kg (0.5 to 1 lb) per week is often recommended for lean muscle gain. Rapid weight changes can be unhealthy and unsustainable.

What if my goal weight falls outside the calculator's range?

If your target weight is significantly different from the calculated healthy range, it's essential to consult with a healthcare professional. Factors like high muscle mass, specific medical conditions, or unique body types might necessitate a personalized approach. The calculator provides an estimate based on standard guidelines.

Does the calculator account for muscle gain vs. fat loss?

The calculator estimates a target weight range based on BMI and your desired rate of change. While it suggests calorie targets for weight loss or gain, it doesn't differentiate between muscle and fat composition directly. Achieving a specific body composition (e.g., significant muscle gain) requires a tailored exercise and nutrition plan beyond basic calorie calculations.

How often should I recalculate my goal weight?

Your weight goals might change as your body composition, fitness level, or health objectives evolve. It's advisable to reassess your {primary_keyword} annually or whenever significant changes occur in your lifestyle or health status. Regularly checking in with your current weight and BMI is also beneficial.

What's the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the energy your body burns at complete rest, like during sleep. TDEE (Total Daily Energy Expenditure) includes your BMR plus all the calories burned through daily activities, exercise, and the thermic effect of food. TDEE is a more accurate reflection of your total daily calorie needs.

Can I use this calculator for children or teenagers?

This calculator is designed for adults. Children and teenagers are still growing and developing, and their nutritional and weight needs are different. Weight management for minors should always be supervised by a pediatrician or a qualified healthcare provider.

Related Tools and Internal Resources

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Disclaimer: The information provided by this calculator and article is for general guidance only and does not constitute medical advice. Always consult with a qualified healthcare professional before making any decisions about your health or weight management plan.

var currentWeightInput = document.getElementById("currentWeight"); var heightInput = document.getElementById("height"); var activityLevelSelect = document.getElementById("activityLevel"); var weightGoalSelect = document.getElementById("weightGoal"); var targetWeightChangeInput = document.getElementById("targetWeightChange"); var resultDiv = document.getElementById("result"); var mainResultSpan = document.getElementById("mainResult"); var bmiRangeSpan = document.getElementById("bmiRange"); var bmrValueSpan = document.getElementById("bmrValue"); var tdeeValueSpan = document.getElementById("tdeeValue"); var currentWeightError = document.getElementById("currentWeightError"); var heightError = document.getElementById("heightError"); var targetWeightChangeError = document.getElementById("targetWeightChangeError"); var bmiTableBody = document.getElementById("bmiTableBody"); var chart = null; var chartContext = null; var myChartCanvas = document.getElementById("myChart"); function validateInput(value, errorElement, fieldName, minValue = 0, maxValue = Infinity) { var errors = []; if (value === "") { errors.push(fieldName + " cannot be empty."); } else { var numValue = parseFloat(value); if (isNaN(numValue)) { errors.push(fieldName + " must be a number."); } else { if (numValue maxValue) { errors.push(fieldName + " cannot exceed " + maxValue + "."); } } } if (errors.length > 0) { errorElement.innerHTML = errors.join(""); errorElement.style.display = "block"; return false; } else { errorElement.innerHTML = ""; errorElement.style.display = "none"; return true; } } function calculateBmi(weightKg, heightCm) { if (weightKg <= 0 || heightCm <= 0) return 0; var heightM = heightCm / 100; return weightKg / (heightM * heightM); } function calculateTdee(weightKg, heightCm, activityFactor) { if (weightKg <= 0 || heightCm <= 0) return 0; // Simplified BMR calculation for calculator (omitting age) // For men: BMR = (10 * W) + (6.25 * H) + 5 // For women: BMR = (10 * W) + (6.25 * H) – 161 // We'll average or use a general approach if gender isn't specified. // Let's use a general approximation: var estimatedBmr = (10 * weightKg) + (6.25 * heightCm) – 100; // Simplified baseline, adjust baseline as needed return estimatedBmr * activityFactor; } function populateBmiTable(heightCm) { if (heightCm <= 0) return; var heightM = heightCm / 100; bmiTableBody.innerHTML = ""; // Clear existing rows var bmiCategories = [ { name: "Underweight", minBmi: 0, maxBmi: 18.4, weightKg: "" }, { name: "Normal weight", minBmi: 18.5, maxBmi: 24.9, weightKg: "" }, { name: "Overweight", minBmi: 25, maxBmi: 29.9, weightKg: "" }, { name: "Obesity Class I", minBmi: 30, maxBmi: 34.9, weightKg: "" }, { name: "Obesity Class II", minBmi: 35, maxBmi: 39.9, weightKg: "" }, { name: "Obesity Class III", minBmi: 40, maxBmi: Infinity, weightKg: "" } ]; bmiCategories.forEach(function(category) { var minWeight = category.minBmi * heightM * heightM; var maxWeight = category.maxBmi * heightM * heightM; if (category.name === "Underweight") { category.weightKg = " " + (category.minBmi * heightM * heightM).toFixed(1) + " kg"; } else { category.weightKg = minWeight.toFixed(1) + " – " + maxWeight.toFixed(1) + " kg"; } var row = bmiTableBody.insertRow(); var cell1 = row.insertCell(0); var cell2 = row.insertCell(1); var cell3 = row.insertCell(2); cell1.textContent = category.name; cell2.textContent = category.minBmi === 0 ? "< " + category.maxBmi : category.minBmi + " – " + category.maxBmi; cell3.textContent = category.weightKg; }); } function updateChart() { if (!chart) { if (myChartCanvas) { chartContext = myChartCanvas.getContext("2d"); chart = new Chart(chartContext, { type: 'line', data: { labels: [], datasets: [{ label: 'Current Weight Trend', data: [], borderColor: 'rgb(75, 192, 192)', tension: 0.1, fill: false }, { label: 'Goal Weight', data: [], borderColor: 'rgb(255, 99, 132)', tension: 0.1, fill: false, borderDash: [5, 5] }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: false } } } }); } } var currentWeight = parseFloat(currentWeightInput.value); var targetWeightChangePerWeek = parseFloat(targetWeightChangeInput.value); var goalWeightInput = parseFloat(mainResultSpan.innerText.split(' ')[0]); // Extract number from goal weight string if (isNaN(currentWeight) || isNaN(targetWeightChangePerWeek) || isNaN(goalWeightInput) || goalWeightInput === 0) { // Clear chart if inputs are invalid chart.data.labels = []; chart.data.datasets[0].data = []; chart.data.datasets[1].data = []; chart.update(); return; } var labels = []; var currentWeightData = []; var goalWeightData = []; var weeks = 26; // Project for 26 weeks // Calculate current weight projection for (var i = 0; i 0) { // If aiming to lose, slightly lower goal weight if current is high, or higher if current is low but still within range if (currentBmi > targetBmi + 2) { // If significantly overweight goalWeight = Math.max(goalWeight – (targetWeightChange * 5 * 7), goalWeight – 10); // Adjust based on target rate, capped } else { goalWeight = Math.max(goalWeight – (targetWeightChange * 2 * 7), goalWeight – 5); // Smaller adjustment if closer } } else if (weightGoal === "gain" && targetWeightChange < 0) { // targetWeightChange is negative for gain // If aiming to gain, slightly higher goal weight if current is low, or lower if current is high but still within range if (currentBmi 0) { suggestedCalorieIntake = tdee – (targetWeightChange * caloriesPerKg); } else if (weightGoal === "gain" && targetWeightChange < 0) { // targetWeightChange is negative for gain suggestedCalorieIntake = tdee – (targetWeightChange * caloriesPerKg); } else { // Maintenance targetWeightChange = 0; // Ensure it's zero for maintenance suggestedCalorieIntake = tdee; } // Ensure suggested intake is reasonable (e.g., not below BMR) var minCalForWeight = calculateTdee(goalWeight, height, 1.2); // BMR with sedentary factor suggestedCalorieIntake = Math.max(minCalForWeight, suggestedCalorieIntake); mainResultSpan.innerText = goalWeight.toFixed(1) + " kg"; bmiRangeSpan.innerText = targetBmi.toFixed(1) + " – " + (targetBmi + 3).toFixed(1) + " (BMI)"; // Show a small range around target bmrValueSpan.innerText = minCalForWeight.toFixed(0) + " kcal"; // Show BMR based on goal weight tdeeValueSpan.innerText = suggestedCalorieIntake.toFixed(0) + " kcal"; // Show suggested TDEE/intake // Update BMI table based on current height populateBmiTable(height); // Update chart updateChart(); resultDiv.style.display = "block"; } function resetCalculator() { currentWeightInput.value = "75"; heightInput.value = "175"; activityLevelSelect.value = "1.55"; weightGoalSelect.value = "lose"; targetWeightChangeInput.value = "0.5"; currentWeightError.innerHTML = ""; currentWeightError.style.display = "none"; heightError.innerHTML = ""; heightError.style.display = "none"; targetWeightChangeError.innerHTML = ""; targetWeightChangeError.style.display = "none"; resultDiv.style.display = "none"; if (chart) { chart.data.labels = []; chart.data.datasets[0].data = []; chart.data.datasets[1].data = []; chart.update(); } // Clear the BMI table too if(bmiTableBody) { bmiTableBody.innerHTML = ""; } } function copyResults() { var currentWeight = currentWeightInput.value; var height = heightInput.value; var activityLevel = activityLevelSelect.options[activityLevelSelect.selectedIndex].text; var weightGoal = weightGoalSelect.value; var targetWeightChange = targetWeightChangeInput.value; var mainResult = mainResultSpan.innerText; var bmiRange = bmiRangeSpan.innerText; var bmrValue = bmrValueSpan.innerText; var tdeeValue = tdeeValueSpan.innerText; var resultText = "— Goal Weight Calculation Results —\n\n"; resultText += "Inputs:\n"; resultText += "- Current Weight: " + currentWeight + " kg\n"; resultText += "- Height: " + height + " cm\n"; resultText += "- Activity Level: " + activityLevel + "\n"; resultText += "- Weight Goal: " + weightGoal.charAt(0).toUpperCase() + weightGoal.slice(1) + "\n"; resultText += "- Target Weekly Change: " + targetWeightChange + " kg\n\n"; resultText += "Key Outputs:\n"; resultText += "- Estimated Goal Weight: " + mainResult + "\n"; resultText += "- Healthy BMI Range: " + bmiRange + "\n"; resultText += "- Estimated BMR (Goal Weight): " + bmrValue + "\n"; resultText += "- Suggested Daily Calorie Intake: " + tdeeValue + "\n\n"; resultText += "Note: Calculations are estimates. Consult a healthcare professional for personalized advice."; try { navigator.clipboard.writeText(resultText).then(function() { alert("Results copied to clipboard!"); }).catch(function(err) { console.error("Failed to copy text: ", err); alert("Failed to copy results. Please copy manually."); }); } catch (e) { console.error("Clipboard API not available: ", e); alert("Clipboard API not available. Please copy manually."); } } function toggleFaq(element) { var content = element.nextElementSibling; if (content.style.display === "block") { content.style.display = "none"; } else { content.style.display = "block"; } } // Initial population of table and chart update on load if defaults are set document.addEventListener('DOMContentLoaded', function() { resetCalculator(); // Set defaults and populate table calculateGoalWeight(); // Run calculation once on load with defaults });

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