Best Tdee Calculator to Lose Weight

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Best TDEE Calculator to Lose Weight

Accurately determine your Total Daily Energy Expenditure (TDEE) to achieve your weight loss goals.

TDEE & Weight Loss Calculator

Male Female Select your gender.
Enter your age in years.
Enter your weight in kilograms (kg).
Enter your height in centimeters (cm).
Sedentary (little or no exercise) Lightly active (light exercise/sports 1-3 days/week) Moderately active (moderate exercise/sports 3-5 days/week) Very active (hard exercise/sports 6-7 days a week) Extra active (very hard exercise/sports & physical job) How active are you on average?
Recommended: 0.5 – 1 kg per week.

Your Weight Loss Plan

— kcal
BMR: — kcal
Maintenance Calories (TDEE): — kcal
Target Calories for Weight Loss: — kcal
Protein Goal: — g
Fat Goal: — g

How it works:

1. BMR (Basal Metabolic Rate): Calculated using the Mifflin-St Jeor equation, estimating calories burned at rest.

2. TDEE (Total Daily Energy Expenditure): BMR is multiplied by your activity level to estimate daily calorie needs for maintaining current weight.

3. Weight Loss Calories: A deficit of 500-1000 kcal per day is created from TDEE for a 0.5-1 kg weekly loss (approx. 3500 kcal per kg of fat).

4. Macronutrient Goals: Protein is set at 1.6-2.2g per kg of body weight, fat at 20-30% of target calories, and remaining calories from carbohydrates.

Calorie Intake Projection

Projected weekly calorie intake for weight loss.

Weight Loss Calculator Assumptions & Results
Metric Value Unit
Gender
Age Years
Weight kg
Height cm
Activity Level Multiplier
BMR kcal/day
Maintenance Calories (TDEE) kcal/day
Weight Loss Goal kg/week
Target Daily Calories kcal/day
Target Protein Intake g/day
Target Fat Intake g/day
Target Carbohydrate Intake g/day

What is a TDEE Calculator for Weight Loss?

A TDEE calculator, specifically one geared towards weight loss, is an essential online tool designed to estimate your Total Daily Energy Expenditure (TDEE). This value represents the total number of calories your body burns in a 24-hour period, including all daily activities and exercise. For individuals aiming to lose weight, understanding your TDEE is the foundational step because it allows you to create a calorie deficit – consuming fewer calories than your body expends – which is necessary for shedding fat.

This TDEE calculator to lose weight takes into account several key personal factors: your gender, age, weight, height, and crucially, your activity level. By inputting these details, the calculator uses established scientific formulas to provide an accurate estimate of your metabolic rate. The primary goal when using a TDEE calculator for weight loss is to determine a daily calorie intake that is lower than your TDEE, prompting your body to use stored fat for energy.

Who Should Use a TDEE Calculator for Weight Loss?

  • Individuals looking to lose body fat in a sustainable and healthy manner.
  • Anyone seeking to understand their baseline calorie needs before starting a diet or exercise program.
  • People who have tried dieting without success and need to re-evaluate their calorie targets.
  • Fitness enthusiasts wanting to optimize their nutrition for body composition changes.
  • Those who need a personalized calorie target rather than a generic recommendation.

Common Misconceptions about TDEE Calculators

  • Myth: A TDEE calculator gives an exact, unchanging number. Reality: TDEE is an estimate that can fluctuate based on daily activity, hormones, and even environmental factors.
  • Myth: Eating significantly below your TDEE is always best for fast weight loss. Reality: Extreme deficits can harm metabolism, muscle mass, and overall health. A moderate deficit is more sustainable.
  • Myth: Activity level multipliers are universally accurate. Reality: These are estimates; individual metabolic rates vary.
  • Myth: TDEE calculators only focus on calories, ignoring nutrition. Reality: While TDEE is about energy balance, effective weight loss also requires balanced macronutrients for health and satiety.

TDEE Calculator Formula and Mathematical Explanation

The most common and scientifically validated method for calculating TDEE, and thus creating a TDEE calculator to lose weight, involves two main steps: calculating Basal Metabolic Rate (BMR) and then multiplying it by an Activity Factor.

Step 1: Calculating Basal Metabolic Rate (BMR)

We use the Mifflin-St Jeor equation, which is considered more accurate than the older Harris-Benedict equation for most individuals.

  • For Men: BMR = (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) + 5
  • For Women: BMR = (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) – 161

Step 2: Calculating Total Daily Energy Expenditure (TDEE)

Once BMR is calculated, it's multiplied by an Activity Factor (AF) that estimates the calories burned through daily activities and exercise.

TDEE = BMR * Activity Factor

The Activity Factors used in this best TDEE calculator to lose weight are standard estimates:

  • Sedentary (little or no exercise): AF = 1.2
  • Lightly active (light exercise/sports 1-3 days/week): AF = 1.375
  • Moderately active (moderate exercise/sports 3-5 days/week): AF = 1.55
  • Very active (hard exercise/sports 6-7 days a week): AF = 1.725
  • Extra active (very hard exercise/sports & physical job): AF = 1.9

Step 3: Determining Target Calories for Weight Loss

To lose weight, you need to consume fewer calories than your TDEE. A common recommendation is to create a deficit of 500-1000 calories per day, which typically leads to a loss of 0.5-1 kg (about 1-2 lbs) per week, as 1 kg of fat is roughly equivalent to 7700 calories.

Target Daily Calories = TDEE – Calorie Deficit

For a target of losing 'X' kg per week:

Calorie Deficit = X * 7700 / 7 (calories per day)

This calculator simplifies this by directly subtracting your chosen weekly goal (adjusted for daily deficit) from your TDEE.

Step 4: Calculating Macronutrient Goals

Once target daily calories are set, macronutrient targets are estimated:

  • Protein: Recommended range is typically 1.6 to 2.2 grams per kilogram of body weight. This helps preserve muscle mass during weight loss.
  • Fat: Often set at 20-30% of total target calories. Fat is essential for hormone function and nutrient absorption. (1 gram of fat = 9 calories)
  • Carbohydrates: The remaining calories are allocated to carbohydrates, which provide energy. (1 gram of carbohydrate = 4 calories)

Variables Table

Variable Meaning Unit Typical Range / Notes
Gender Biological sex influencing metabolic rate Male / Female Used in BMR calculation
Age Years since birth Years Affects metabolic rate; generally decreases with age
Weight Body mass Kilograms (kg) 1 kg ≈ 2.2 lbs. Crucial for BMR and macro calculations.
Height Body stature Centimeters (cm) 1 inch = 2.54 cm. Used in BMR calculation.
Activity Level Average weekly physical exertion Multiplier (e.g., 1.2-1.9) Determines TDEE adjustment from BMR
Weight Loss Goal Desired rate of weight reduction kg per week Recommended: 0.5 – 1 kg/week for sustainability
BMR Basal Metabolic Rate kcal/day Calories burned at complete rest
TDEE Total Daily Energy Expenditure kcal/day Total calories burned per day; Maintenance level
Target Daily Calories Daily calorie intake for weight loss kcal/day TDEE minus a calorie deficit
Protein Macronutrient for muscle repair and satiety grams/day 1.6 – 2.2 g/kg body weight
Fat Macronutrient for hormone function and energy grams/day 20-30% of target calories (9 kcal/g)
Carbohydrates Macronutrient for primary energy source grams/day Remaining calories (4 kcal/g)

Practical Examples (Real-World Use Cases)

Example 1: Sarah, Aiming for Moderate Weight Loss

Sarah is a 35-year-old female, 168 cm tall, weighing 75 kg. She works an office job but goes to the gym for moderate exercise 3-4 times a week. She wants to lose about 0.7 kg per week.

  • Inputs: Gender: Female, Age: 35, Weight: 75 kg, Height: 168 cm, Activity Level: Moderately active (1.55), Weight Loss Goal: 0.7 kg/week.
  • Calculations:
    • BMR = (10 * 75) + (6.25 * 168) – (5 * 35) – 161 = 750 + 1050 – 175 – 161 = 1464 kcal
    • TDEE = 1464 * 1.55 = 2269 kcal
    • Calorie Deficit for 0.7 kg/week loss ≈ (0.7 * 7700) / 7 ≈ 770 kcal/day
    • Target Daily Calories = 2269 – 770 = 1499 kcal (rounded to 1500 kcal)
    • Protein Goal: 1.8 g/kg * 75 kg = 135 g
    • Fat Goal: 25% of 1500 kcal = 375 kcal / 9 kcal/g = 42 g
    • Carbohydrate Goal: (1500 – (135*4) – (42*9)) / 4 = (1500 – 540 – 378) / 4 = 582 / 4 = 145 g
  • Results: Sarah's estimated TDEE is 2269 kcal. To lose 0.7 kg per week, her target daily intake should be approximately 1500 kcal, with goals of 135g protein, 42g fat, and 145g carbohydrates.
  • Interpretation: Sarah needs to be mindful of portion sizes and choose nutrient-dense foods to meet her targets within a 1500-calorie budget. This approach ensures a significant but manageable deficit for sustainable weight loss.

Example 2: Mark, Aggressive Fat Loss Phase

Mark is a 28-year-old male, 185 cm tall, weighing 90 kg. He trains intensely 5-6 days a week and wants to lose 1 kg per week for a specific event.

  • Inputs: Gender: Male, Age: 28, Weight: 90 kg, Height: 185 cm, Activity Level: Very active (1.725), Weight Loss Goal: 1 kg/week.
  • Calculations:
    • BMR = (10 * 90) + (6.25 * 185) – (5 * 28) + 5 = 900 + 1156.25 – 140 + 5 = 1921.25 kcal
    • TDEE = 1921.25 * 1.725 = 3315.66 kcal
    • Calorie Deficit for 1 kg/week loss ≈ (1 * 7700) / 7 ≈ 1100 kcal/day
    • Target Daily Calories = 3316 – 1100 = 2216 kcal (rounded to 2200 kcal)
    • Protein Goal: 2.0 g/kg * 90 kg = 180 g
    • Fat Goal: 20% of 2200 kcal = 440 kcal / 9 kcal/g = 49 g
    • Carbohydrate Goal: (2200 – (180*4) – (49*9)) / 4 = (2200 – 720 – 441) / 4 = 1039 / 4 = 260 g
  • Results: Mark's estimated TDEE is 3316 kcal. To lose 1 kg per week, his target daily intake should be approximately 2200 kcal, with goals of 180g protein, 49g fat, and 260g carbohydrates.
  • Interpretation: Mark can sustain a larger deficit due to his high activity level and muscle mass. This aggressive target requires careful meal planning to ensure adequate nutrient intake while maintaining energy for intense workouts. It's crucial to monitor energy levels and recovery.

How to Use This TDEE Calculator for Weight Loss

Using this TDEE calculator to lose weight is straightforward. Follow these steps:

Step 1: Gather Your Information

Before you start, have the following details ready:

  • Your current weight in kilograms (kg).
  • Your height in centimeters (cm).
  • Your age in years.
  • Your gender (Male/Female).
  • An honest assessment of your average weekly physical activity level.
  • Your desired weekly weight loss rate (e.g., 0.5 kg, 1 kg).

Step 2: Input Your Details

Enter your information into the corresponding fields on the calculator:

  • Select your Gender from the dropdown.
  • Enter your Age.
  • Enter your Weight in kg.
  • Enter your Height in cm.
  • Choose your Activity Level from the options provided, based on your lifestyle.
  • Specify your desired Weight Loss Goal in kg per week.

As you input your data, the calculator will perform real-time calculations. Ensure you enter valid numerical data; error messages will appear if inputs are missing or invalid.

Step 3: Understand the Results

Once you click "Calculate TDEE & Macros", you will see:

  • Primary Result (Target Calories for Weight Loss): This is the most critical number – the daily calorie intake you should aim for to achieve your weight loss goal.
  • BMR: Your Basal Metabolic Rate, the calories burned at rest.
  • Maintenance Calories (TDEE): The calories needed to maintain your current weight.
  • Macronutrient Goals (Protein, Fat, Carbohydrates): These provide a balanced nutritional breakdown to support your health and weight loss efforts.

The table provides a detailed breakdown of all inputs and calculated outputs for your reference.

Step 4: Make Decisions and Adjust

Use the calculated Target Daily Calories as your guide. This number represents a starting point. Weight loss is a dynamic process:

  • Consistency is Key: Adhere to your calorie target as consistently as possible.
  • Monitor Progress: Track your weight loss weekly. If you aren't losing at your desired rate, you might need to slightly decrease your calorie intake or increase activity. If you're losing too quickly or feeling excessively fatigued, you may need to increase calories slightly.
  • Listen to Your Body: Ensure you feel energized and well-nourished. Extreme hunger or fatigue may indicate the deficit is too large.
  • The 'Copy Results' Button: Use this to easily save or share your calculated plan.

Key Factors That Affect TDEE Results

While this TDEE calculator to lose weight provides a robust estimate, several factors can influence your actual TDEE and weight loss journey:

  1. Muscle Mass vs. Fat Mass: Muscle tissue is metabolically more active than fat tissue. Individuals with higher muscle mass generally have a higher BMR and TDEE than someone of the same weight with lower muscle mass. This calculator uses weight, but body composition plays a significant role.
  2. Metabolic Adaptations: As you lose weight, your body requires fewer calories to function. Your TDEE will naturally decrease. This means you may need to adjust your calorie intake downwards over time to continue losing weight. This is known as metabolic adaptation.
  3. Hormonal Fluctuations: Hormones like thyroid hormones (thyroxine), cortisol, and leptin significantly impact metabolism. Imbalances or conditions like hypothyroidism can drastically lower TDEE, while stress (high cortisol) can affect energy storage.
  4. Thermic Effect of Food (TEF): Your body burns calories digesting and absorbing food. Protein has a higher TEF than carbohydrates or fats. While factored in generally by activity multipliers, specific diets rich in protein can slightly increase overall calorie expenditure.
  5. Genetics: Individual genetic makeup plays a role in metabolic rate. Some people naturally burn more calories at rest than others, even with similar body composition and activity levels.
  6. Age: Metabolism tends to slow down with age, partly due to a natural decrease in muscle mass and hormonal changes. The Mifflin-St Jeor equation accounts for this directly by including age as a variable.
  7. Environmental Factors: Extreme temperatures (both hot and cold) can cause your body to expend extra energy to maintain its core temperature, slightly increasing TDEE.
  8. Sleep Quality and Quantity: Poor sleep can negatively impact hormones that regulate appetite (ghrelin and leptin) and stress hormones (cortisol), potentially affecting metabolism and increasing cravings.

Frequently Asked Questions (FAQ)

What is the most accurate TDEE formula?

The Mifflin-St Jeor equation, used in this calculator, is widely considered the most accurate for estimating BMR in most adults. TDEE is then derived by multiplying BMR by an activity factor, which is an estimation. Individual variations exist.

Can I lose weight eating exactly my TDEE?

No. Eating at your TDEE means you are consuming the same number of calories your body burns, resulting in weight maintenance. To lose weight, you must consistently consume fewer calories than your TDEE to create a calorie deficit.

How much of a deficit is safe for weight loss?

A safe and sustainable deficit is generally 500-1000 calories per day, aiming for 0.5-1 kg (1-2 lbs) of weight loss per week. Larger deficits can lead to muscle loss, nutrient deficiencies, fatigue, and are harder to maintain long-term.

What if my activity level changes?

If your activity level changes significantly (e.g., starting a new exercise routine or becoming more sedentary), you should recalculate your TDEE using the updated activity level to get a more accurate target calorie intake.

Does the calculator account for muscle gain?

This calculator primarily focuses on calorie needs for weight loss. While it provides protein recommendations to help preserve muscle, it doesn't directly calculate for simultaneous muscle gain (body recomposition) which requires a more nuanced approach, often involving calorie cycling or a slight surplus with high protein.

Why are macros important for weight loss?

Macronutrients (protein, fats, carbs) provide your body with energy and essential functions. Adequate protein helps preserve muscle mass during a calorie deficit, keeping metabolism higher. Healthy fats are crucial for hormones, and carbohydrates provide energy for daily activities and exercise. Balanced macros support satiety and overall health, making weight loss more sustainable.

Can I use this calculator if I'm pregnant or breastfeeding?

No. This calculator is not suitable for pregnant or breastfeeding individuals. Calorie and nutrient needs are significantly different during these periods and require personalized guidance from a healthcare professional or registered dietitian.

How often should I update my TDEE calculation?

You should recalculate your TDEE whenever significant changes occur in your body weight, body composition, or activity level. For steady weight loss, it's generally recommended to re-evaluate every 10-15 lbs lost or every few months to adjust your targets as your metabolism adapts.

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// Global variables for chart var calorieChart = null; var chartContext = null; function getElement(id) { return document.getElementById(id); } function setBMRValue(bmr) { var bmrResultElement = getElement("bmrResult").getElementsByTagName("span")[0]; var tableBMR = getElement("tableBMR"); if (bmrResultElement) { bmrResultElement.textContent = bmr.toFixed(0) + " kcal"; } if(tableBMR) { tableBMR.textContent = bmr.toFixed(0); } } function setTDEEValue(tdee) { var tdeeResultElement = getElement("maintenanceCaloriesResult").getElementsByTagName("span")[0]; var tableTDEE = getElement("tableTDEE"); if (tdeeResultElement) { tdeeResultElement.textContent = tdee.toFixed(0) + " kcal"; } if(tableTDEE) { tableTDEE.textContent = tdee.toFixed(0); } } function setTargetCaloriesValue(targetCalories) { var targetCaloriesResultElement = getElement("targetCaloriesResult").getElementsByTagName("span")[0]; var tableTargetCalories = getElement("tableTargetCalories"); if (targetCaloriesResultElement) { targetCaloriesResultElement.textContent = targetCalories.toFixed(0) + " kcal"; } if(tableTargetCalories) { tableTargetCalories.textContent = targetCalories.toFixed(0); } getElement("tdeeResult").textContent = targetCalories.toFixed(0) + " kcal"; } function setMacroValues(protein, fat, carbs) { var proteinResultElement = getElement("proteinResult").getElementsByTagName("span")[0]; var fatResultElement = getElement("fatResult").getElementsByTagName("span")[0]; var tableProtein = getElement("tableProtein"); var tableFat = getElement("tableFat"); var tableCarbs = getElement("tableCarbs"); if (proteinResultElement) proteinResultElement.textContent = protein.toFixed(0) + " g"; if (fatResultElement) fatResultElement.textContent = fat.toFixed(0) + " g"; if(tableProtein) tableProtein.textContent = protein.toFixed(0); if(tableFat) tableFat.textContent = fat.toFixed(0); if(tableCarbs) tableCarbs.textContent = carbs.toFixed(0); } function updateTable(id, value) { var element = getElement(id); if(element) { element.textContent = value; } } function calculateTDEE() { var gender = getElement("gender").value; var age = parseInt(getElement("age").value); var weightKg = parseFloat(getElement("weightKg").value); var heightCm = parseFloat(getElement("heightCm").value); var activityLevel = parseFloat(getElement("activityLevel").value); var weightLossGoal = parseFloat(getElement("weightLossGoal").value); var ageError = getElement("ageError"); var weightKgError = getElement("weightKgError"); var heightCmError = getElement("heightCmError"); var weightLossGoalError = getElement("weightLossGoalError"); // Reset errors ageError.style.display = "none"; weightKgError.style.display = "none"; heightCmError.style.display = "none"; weightLossGoalError.style.display = "none"; var isValid = true; if (isNaN(age) || age <= 0) { ageError.textContent = "Please enter a valid age."; ageError.style.display = "block"; isValid = false; } if (isNaN(weightKg) || weightKg <= 0) { weightKgError.textContent = "Please enter a valid weight."; weightKgError.style.display = "block"; isValid = false; } if (isNaN(heightCm) || heightCm <= 0) { heightCmError.textContent = "Please enter a valid height."; heightCmError.style.display = "block"; isValid = false; } if (isNaN(weightLossGoal) || weightLossGoal 2) { // Allowing up to 2kg/week for very active individuals, but warning weightLossGoalError.textContent = "Please enter a valid weight loss goal (0.25 – 2 kg/week recommended)."; weightLossGoalError.style.display = "block"; isValid = false; } if (weightLossGoal > 1.0) { // Optional: Warn about aggressive goals console.warn("Aggressive weight loss goal selected. Ensure it's sustainable and healthy."); } if (!isValid) { return; } var bmr = 0; if (gender === "male") { bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) + 5; } else { // female bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) – 161; } var tdee = bmr * activityLevel; var calorieDeficitPerDay = weightLossGoal * 1100; // Approximately 7700 kcal per kg, divided by 7 days var targetCalories = tdee – calorieDeficitPerDay; // Ensure target calories don't go below a safe minimum (e.g., 1200 kcal for women, 1500 for men) var minCalories = (gender === "female") ? 1200 : 1500; if (targetCalories < minCalories) { targetCalories = minCalories; // Optionally, show a message that the goal might be too aggressive for this deficit console.log("Target calories adjusted to minimum safe level."); } // Macronutrient calculations var proteinGoal = 0; // Adjust protein based on weight and goal, common range 1.6-2.2 g/kg proteinGoal = Math.max(1.6, Math.min(2.2, 1.6 + (weightLossGoal * 0.5))) * weightKg; // Scales slightly with goal, capped proteinGoal = Math.max(proteinGoal, 100); // Ensure a minimum protein intake var fatPercentage = 0.25; // Default to 25% if (targetCalories 2500) fatPercentage = 0.30; // Higher fat percentage for higher calories var fatCalories = targetCalories * fatPercentage; var fatGrams = fatCalories / 9; var proteinCalories = proteinGoal * 4; var carbsCalories = targetCalories – proteinCalories – fatCalories; var carbsGrams = carbsCalories / 4; // Ensure carbs are not negative if (carbsGrams < 0) { carbsGrams = 0; // Recalculate fat if carbs become zero var remainingCaloriesForFat = targetCalories – proteinCalories; fatGrams = remainingCaloriesForFat / 9; } setBMRValue(bmr); setTDEEValue(tdee); setTargetCaloriesValue(targetCalories); setMacroValues(proteinGoal, fatGrams, carbsGrams); // Update table updateTable("tableGender", gender === "male" ? "Male" : "Female"); updateTable("tableAge", age); updateTable("tableWeight", weightKg); updateTable("tableHeight", heightCm); updateTable("tableActivity", activityLevel); updateTable("tableBMR", bmr.toFixed(0)); updateTable("tableTDEE", tdee.toFixed(0)); updateTable("tableLossGoal", weightLossGoal); updateTable("tableTargetCalories", targetCalories.toFixed(0)); updateTable("tableProtein", proteinGoal.toFixed(0)); updateTable("tableFat", fatGrams.toFixed(0)); updateTable("tableCarbs", carbsGrams.toFixed(0)); updateChart(targetCalories); } function resetCalculator() { getElement("gender").value = "male"; getElement("age").value = ""; getElement("weightKg").value = ""; getElement("heightCm").value = ""; getElement("activityLevel").value = "1.2"; getElement("weightLossGoal").value = "0.5"; // Reset results display setBMRValue(0); setTDEEValue(0); setTargetCaloriesValue(0); setMacroValues(0, 0, 0); // Reset table updateTable("tableGender", "–"); updateTable("tableAge", "–"); updateTable("tableWeight", "–"); updateTable("tableHeight", "–"); updateTable("tableActivity", "–"); updateTable("tableBMR", "–"); updateTable("tableTDEE", "–"); updateTable("tableLossGoal", "–"); updateTable("tableTargetCalories", "–"); updateTable("tableProtein", "–"); updateTable("tableFat", "–"); updateTable("tableCarbs", "–"); // Clear chart if (chartContext) { chartContext.clearRect(0, 0, chartContext.canvas.width, chartContext.canvas.height); // Optionally destroy and recreate chart instance if needed } // Reset errors getElement("ageError").style.display = "none"; getElement("weightKgError").style.display = "none"; getElement("heightCmError").style.display = "none"; getElement("weightLossGoalError").style.display = "none"; } function copyResults() { var tdeeResult = getElement("tdeeResult").textContent; var bmrResult = getElement("bmrResult").textContent; var maintenanceCaloriesResult = getElement("maintenanceCaloriesResult").textContent; var proteinResult = getElement("proteinResult").textContent; var fatResult = getElement("fatResult").textContent; var gender = getElement("gender").value === "male" ? "Male" : "Female"; var age = getElement("age").value || "–"; var weightKg = getElement("weightKg").value || "–"; var heightCm = getElement("heightCm").value || "–"; var activityLevelText = getElement("activityLevel").options[getElement("activityLevel").selectedIndex].text; var weightLossGoal = getElement("weightLossGoal").value || "–"; var resultsText = "— Your Weight Loss Plan —\n\n"; resultsText += "Target Daily Calories: " + tdeeResult + "\n"; resultsText += "BMR: " + bmrResult + "\n"; resultsText += "Maintenance Calories (TDEE): " + maintenanceCaloriesResult + "\n"; resultsText += "Protein Goal: " + proteinResult + "\n"; resultsText += "Fat Goal: " + fatResult + "\n\n"; // Assuming fat is displayed, adding carbs if available resultsText += "— Key Assumptions —\n"; resultsText += "Gender: " + gender + "\n"; resultsText += "Age: " + age + "\n"; resultsText += "Weight: " + weightKg + " kg\n"; resultsText += "Height: " + heightCm + " cm\n"; resultsText += "Activity Level: " + activityLevelText + "\n"; resultsText += "Weight Loss Goal: " + weightLossGoal + " kg/week\n"; // Use a temporary textarea to copy text var textArea = document.createElement("textarea"); textArea.value = resultsText; textArea.style.position = "fixed"; textArea.style.left = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied!' : 'Copying failed'; alert(msg); // Simple feedback } catch (err) { alert('Oops, unable to copy'); } document.body.removeChild(textArea); } // — Charting Logic — function updateChart(targetCalories) { var canvas = getElement('calorieProjectionChart'); if (!canvas) return; chartContext = canvas.getContext('2d'); // Clear previous chart if it exists if (calorieChart) { calorieChart.destroy(); } var maintenanceCalories = parseFloat(getElement("tableTDEE").textContent); var weightLossGoal = parseFloat(getElement("tableLossGoal").textContent); // Calculate calorie projection for the next 7 days var labels = []; var dataSeries1 = []; // Maintenance Calories var dataSeries2 = []; // Target Calories for Weight Loss var days = 7; for (var i = 0; i !isNaN(val) && val > 0 ? val : 0); dataSeries2 = dataSeries2.map(val => !isNaN(val) && val > 0 ? val : 0); calorieChart = new Chart(chartContext, { type: 'line', data: { labels: labels, datasets: [{ label: 'Maintenance Calories (TDEE)', data: dataSeries1, borderColor: '#004a99', backgroundColor: 'rgba(0, 74, 153, 0.1)', fill: false, tension: 0.1 }, { label: 'Target Calories for Weight Loss', data: dataSeries2, borderColor: '#28a745', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: false, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: true, scales: { y: { beginAtZero: false, title: { display: true, text: 'Calories (kcal)' } } }, plugins: { legend: { position: 'top', }, title: { display: true, text: 'Daily Calorie Projection (7 Days)' } } } }); } // — FAQ Toggle — function toggleFaq(element) { var content = element.nextElementSibling; var display = window.getComputedStyle(content).display; content.style.display = (display === 'none') ? 'block' : 'none'; } // — Initial Setup — // Add event listeners for input changes to update results dynamically window.onload = function() { // Use setTimeout to ensure canvas is rendered before charting setTimeout(function() { var canvas = getElement('calorieProjectionChart'); if(canvas) { chartContext = canvas.getContext('2d'); // Initialize with default or placeholder data if inputs are empty updateChart(0); // Initialize chart with zero or placeholder values } // Add listeners after initial chart setup var inputs = document.querySelectorAll('#tdee-calculator input, #tdee-calculator select'); for (var i = 0; i < inputs.length; i++) { inputs[i].addEventListener('input', calculateTDEE); inputs[i].addEventListener('change', calculateTDEE); } // Trigger initial calculation if defaults are set if (getElement("age").value || getElement("weightKg").value || getElement("heightCm").value) { calculateTDEE(); } }, 100); // Small delay };

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