Calories to Burn for Weight Loss Calculator

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Calories to Burn for Weight Loss Calculator

Your current body weight in kilograms.
Your desired body weight in kilograms.
The amount of weight you aim to lose each week (typically 0.5-1 kg).
Sedentary (little to 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/week) Extra Active (very hard exercise/sports & physical job) Your average daily physical activity.
Harris-Benedict (Revised) Mifflin-St Jeor Choose a method for estimating Basal Metabolic Rate.
Male Female Required for BMR calculation.
Your current age in years.
Your current height in centimeters.

Your Weight Loss Target

— kcal

Estimated Daily Calorie Needs (TDEE): — kcal

Required Weekly Calorie Deficit: — kcal

Estimated Time to Reach Goal: — days

This calculator estimates your daily calorie burn (TDEE) and determines the deficit needed to achieve your weight loss goal. A deficit of approximately 3500 kcal is needed to lose 0.5 kg (1 lb) of fat.

Estimated Calorie Burn Over Time

Daily calorie needs and target intake for weight loss.

Calculation Summary Table

Metric Value Unit
Current Weightkg
Target Weightkg
Weekly Goalkg/week
BMRkcal
TDEEkcal
Daily Deficit Requiredkcal/day
Weekly Deficit Requiredkcal/week
Estimated Time to Goaldays

What is Calories to Burn for Weight Loss?

The concept of "Calories to Burn for Weight Loss" refers to the amount of energy (measured in calories) your body needs to expend daily to achieve a caloric deficit, which is the fundamental principle behind losing body fat. Essentially, to lose weight, you must consume fewer calories than your body burns. This calculator helps you quantify that required deficit based on your personal metrics and weight loss goals. It's a crucial tool for anyone embarking on a weight management journey.

Who Should Use It?

Anyone looking to lose weight can benefit from using a Calories to Burn for Weight Loss Calculator. This includes:

  • Individuals aiming for gradual, sustainable weight loss.
  • People who want to understand the science behind their weight loss efforts.
  • Those seeking to set realistic and achievable weight loss targets.
  • Fitness enthusiasts looking to fine-tune their nutrition for body composition goals.
  • Anyone who has tried dieting without success and wants a more data-driven approach.

Common Misconceptions

Several myths surround calorie deficits for weight loss:

  • "You need to drastically cut calories." Extreme calorie restriction is often unsustainable and can lead to nutrient deficiencies and muscle loss. Gradual, moderate deficits are generally more effective and healthier.
  • "All calories are equal." While the energy balance equation is key, the source of calories matters for satiety, nutrient intake, and overall health.
  • "Weight loss is purely about willpower." While discipline is important, understanding your body's metabolic needs (calories to burn) provides a scientific framework that makes willpower more effective.
  • "Cardio is the only way to burn calories." Strength training and even non-exercise activity thermogenesis (NEAT) contribute significantly to your daily calorie expenditure.

Calories to Burn for Weight Loss Formula and Mathematical Explanation

The core of calculating your target calories to burn for weight loss involves understanding your Total Daily Energy Expenditure (TDEE) and then creating a deficit from it. Here's a breakdown:

1. Basal Metabolic Rate (BMR)

This is the number of calories your body burns at rest to maintain basic life functions (breathing, circulation, cell production). We use standard formulas to estimate this:

  • Harris-Benedict (Revised):
    • Men: BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) – (5.677 × age in years)
    • Women: BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) – (4.330 × age in years)
  • Mifflin-St Jeor:
    • Men: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
    • Women: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161

2. Total Daily Energy Expenditure (TDEE)

TDEE accounts for your BMR plus the calories burned through physical activity and the thermic effect of food (TEF). It's calculated by multiplying your BMR by an activity factor:

  • Sedentary: BMR × 1.2
  • Lightly Active: BMR × 1.375
  • Moderately Active: BMR × 1.55
  • Very Active: BMR × 1.725
  • Extra Active: BMR × 1.9

3. Required Calorie Deficit for Weight Loss

A deficit of approximately 3500 calories is needed to lose 1 pound (0.453 kg) of fat. For kilograms, a deficit of roughly 7700 calories corresponds to 1 kg of fat loss.

Weekly Calorie Deficit = (Target Weekly Weight Loss in kg) × 7700 kcal

4. Target Daily Calorie Intake

To achieve your goal, your daily calorie intake should be your TDEE minus the daily portion of your required weekly deficit.

Daily Calorie Deficit = Weekly Calorie Deficit / 7

Target Daily Intake = TDEE – Daily Calorie Deficit

The "Calories to Burn" in the context of weight loss effectively means maintaining an intake that results in this calculated deficit.

5. Estimated Time to Reach Goal

This indicates how long it might take based on your consistent deficit.

Total Weight Loss Needed (kg) = Current Weight – Target Weight

Total Calorie Deficit Needed = Total Weight Loss Needed × 7700

Estimated Days = Total Calorie Deficit Needed / Daily Calorie Deficit

Variables Table

Variable Meaning Unit Typical Range
Current WeightYour present body mass.kg30 – 300+
Target WeightYour desired body mass.kg30 – 300+
Weekly Weight Loss GoalDesired fat loss rate per week.kg/week0.25 – 1.0 (sustainable)
AgeYour age.years18 – 100+
HeightYour standing height.cm100 – 210
GenderBiological sex, impacts BMR.Male, Female
Activity LevelAverage daily physical exertion.Sedentary to Extra Active
BMRCalories burned at rest.kcal/day800 – 2500+
TDEETotal calories burned daily, including activity.kcal/day1500 – 4000+
Calorie DeficitDifference between TDEE and intake needed for loss.kcal/day250 – 1000+

Practical Examples (Real-World Use Cases)

Example 1: Sarah's Gradual Weight Loss Plan

Sarah is 35 years old, weighs 70 kg, and wants to reach 65 kg. She has a moderately active lifestyle and aims for a sustainable weight loss of 0.5 kg per week. She chooses the Mifflin-St Jeor formula and identifies as female.

  • Inputs: Current Weight: 70 kg, Target Weight: 65 kg, Weekly Goal: 0.5 kg, Age: 35, Height: 165 cm, Gender: Female, Activity: Moderately Active, BMR Method: Mifflin-St Jeor.
  • Calculation Steps:
    • BMR (Female Mifflin-St Jeor): (10 * 70) + (6.25 * 165) – (5 * 35) – 161 = 700 + 1031.25 – 175 – 161 = 1395.25 kcal
    • TDEE (Moderately Active): 1395.25 * 1.55 = 2162.64 kcal
    • Weekly Deficit: 0.5 kg * 7700 kcal/kg = 3850 kcal
    • Daily Deficit: 3850 kcal / 7 = 550 kcal
    • Target Daily Intake: 2162.64 – 550 = 1612.64 kcal
    • Total Weight Loss Needed: 70 kg – 65 kg = 5 kg
    • Total Deficit Needed: 5 kg * 7700 kcal/kg = 38500 kcal
    • Estimated Time: 38500 kcal / 550 kcal/day = 70 days
  • Results: Sarah needs to burn approximately 550 kcal more than she consumes each day. Her target daily intake is around 1613 kcal. It will take her an estimated 70 days to reach her goal weight.

Example 2: Mark's More Active Weight Loss

Mark is 45, weighs 95 kg, and wants to get down to 85 kg. He exercises intensely 5 days a week (Very Active). He aims for a 0.75 kg weekly loss and uses the Revised Harris-Benedict formula, identifying as male.

  • Inputs: Current Weight: 95 kg, Target Weight: 85 kg, Weekly Goal: 0.75 kg, Age: 45, Height: 180 cm, Gender: Male, Activity: Very Active, BMR Method: Harris-Benedict.
  • Calculation Steps:
    • BMR (Male Harris-Benedict Revised): 88.362 + (13.397 * 95) + (4.799 * 180) – (5.677 * 45) = 88.362 + 1272.715 + 863.82 – 255.465 = 1970.432 kcal
    • TDEE (Very Active): 1970.432 * 1.725 = 3400.01 kcal
    • Weekly Deficit: 0.75 kg * 7700 kcal/kg = 5775 kcal
    • Daily Deficit: 5775 kcal / 7 = 825 kcal
    • Target Daily Intake: 3400.01 – 825 = 2575.01 kcal
    • Total Weight Loss Needed: 95 kg – 85 kg = 10 kg
    • Total Deficit Needed: 10 kg * 7700 kcal/kg = 77000 kcal
    • Estimated Time: 77000 kcal / 825 kcal/day = 93.3 days
  • Results: Mark needs a daily deficit of about 825 kcal. His target daily intake is roughly 2575 kcal. Reaching his goal is estimated to take approximately 93 days.

How to Use This Calories to Burn for Weight Loss Calculator

Using this calculator is straightforward. Follow these steps to get your personalized weight loss targets:

  1. Input Current Weight: Enter your current body weight in kilograms.
  2. Input Target Weight: Enter the weight you aim to achieve in kilograms.
  3. Set Weekly Weight Loss Goal: Decide how much weight you want to lose each week. A safe and sustainable rate is typically between 0.5 kg and 1 kg per week. Faster goals require larger deficits, which can be harder to maintain and may lead to muscle loss.
  4. Select Activity Level: Honestly assess your daily physical activity and choose the corresponding level. This significantly impacts your TDEE.
  5. Choose BMR Method: Select either the Harris-Benedict (Revised) or Mifflin-St Jeor equation. Mifflin-St Jeor is often considered more accurate for the general population.
  6. Input Gender, Age, and Height: Provide these basic personal details, essential for BMR calculations.
  7. Click "Calculate": Once all fields are filled, click the calculate button.

How to Read Results

  • Primary Result (Highlighted): This shows your target daily calorie intake to achieve your desired weekly weight loss.
  • Estimated Daily Calorie Needs (TDEE): This is your estimated total calorie expenditure per day.
  • Required Weekly Calorie Deficit: The total calorie deficit you need to achieve each week.
  • Estimated Time to Reach Goal: An approximation of how many days it will take to reach your target weight.

Decision-Making Guidance

Use the results to guide your dietary choices and lifestyle adjustments. Aim to consume calories close to your calculated Target Daily Intake. Combine this with regular physical activity to support your calorie deficit and improve overall health. Remember that these are estimates; listen to your body and consult with a healthcare professional or registered dietitian for personalized advice.

Key Factors That Affect Calories to Burn Results

While the calculator provides a solid estimate, several real-world factors can influence your actual calorie burn and weight loss journey:

  1. Muscle Mass: Muscle tissue is metabolically more active than fat tissue, meaning individuals with higher muscle mass generally have a higher BMR and TDEE. Strength training can increase muscle mass over time, boosting your calorie burn.
  2. Thermic Effect of Food (TEF): Different macronutrients require different amounts of energy to digest. Protein has a higher TEF than carbohydrates or fats, meaning your body burns more calories digesting protein.
  3. Non-Exercise Activity Thermogenesis (NEAT): This includes all the calories you burn from activities outside of formal exercise, such as fidgeting, walking around the office, standing, and performing daily chores. NEAT can vary significantly between individuals and significantly impact TDEE.
  4. Hormonal Factors: Hormones like thyroid hormones, cortisol, and sex hormones play a role in metabolism. Conditions like hypothyroidism can lower your BMR, while stress (high cortisol) can affect fat storage and appetite.
  5. Genetics: Individual genetic makeup influences metabolism, appetite regulation, and how your body stores fat. Some people naturally have a higher or lower metabolic rate.
  6. Sleep Quality and Quantity: Poor sleep can disrupt hormones that regulate appetite (ghrelin and leptin), potentially leading to increased hunger and reduced metabolic rate, making it harder to maintain a calorie deficit.
  7. Age: Metabolism naturally tends to slow down with age, partly due to a decrease in muscle mass. This is why the age factor is included in BMR calculations.
  8. Environmental Temperature: Your body expends energy to maintain its core temperature. In very cold or very hot environments, your metabolic rate might increase slightly.

Frequently Asked Questions (FAQ)

Q1: How accurate is this calculator?

A: This calculator provides an estimate based on established formulas (like Mifflin-St Jeor or Harris-Benedict) and activity multipliers. Individual metabolisms vary, so your actual results may differ slightly. It's a great starting point, but real-world results depend on adherence and individual physiology.

Q2: Is a 0.5 kg weekly weight loss goal safe?

A: Yes, a 0.5 kg (approximately 1 lb) weekly weight loss is generally considered safe, sustainable, and achievable for most people. It requires a consistent daily deficit of about 500 calories.

Q3: What if my TDEE is lower than my target intake?

A: If your target daily intake calculated by the calculator is lower than your estimated TDEE, it means you need to create a deficit. If the target intake is extremely low (e.g., below 1200 kcal for women or 1500 kcal for men), it might be unsustainable or unhealthy. Re-evaluate your weekly goal or consider increasing your activity level.

Q4: How does muscle mass affect calorie needs?

A: Muscle is metabolically active tissue. More muscle mass means a higher BMR and TDEE. If you're strength training and gaining muscle, your TDEE might increase over time, potentially requiring adjustments to your calorie intake to maintain the same rate of weight loss.

Q5: Can I achieve weight loss solely through diet or exercise?

A: While both are important, a combination is most effective. Diet primarily controls calorie intake, while exercise increases calorie expenditure. Focusing on both provides the best results for sustainable weight loss and overall health improvements.

Q6: What should I do if I'm not losing weight despite following the calculator's advice?

A: Double-check your calorie intake accuracy (are you tracking everything?), reassess your activity level (are you burning as much as you think?), consider sleep and stress levels, and ensure you haven't drastically overestimated your TDEE. Consulting a professional can help identify underlying issues.

Q7: How long does it take to lose 1 kg of fat?

A: Approximately 7700 calories is equivalent to 1 kg of body fat. Therefore, creating a consistent daily deficit of roughly 770 calories would theoretically lead to losing 1 kg of fat in about 10 days.

Q8: Should I use the calculator after reaching my target weight?

A: Yes, once you reach your target weight, you can use the calculator again, this time setting your target weight to your current weight and inputting your target weight as your *new* current weight. Then, set your goal to 0 kg or a very small gain (e.g., 0.1 kg/week) to calculate your estimated maintenance calories (TDEE).

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var chart = null; // Global chart variable function validateInput(id, min, max, errorId, errorMessage) { var inputElement = document.getElementById(id); var value = parseFloat(inputElement.value); var errorElement = document.getElementById(errorId); errorElement.style.display = 'none'; // Hide previous errors if (isNaN(value) || inputElement.value.trim() === "") { errorElement.innerText = "This field is required."; errorElement.style.display = 'block'; return false; } if (value max) { errorElement.innerText = `Value must be no more than ${max}.`; errorElement.style.display = 'block'; return false; } return true; } function calculateCalories() { // Input validation var currentWeightValid = validateInput('currentWeight', 1, 300, 'currentWeightError', 'Please enter a valid current weight.'); var targetWeightValid = validateInput('targetWeight', 1, 300, 'targetWeightError', 'Please enter a valid target weight.'); var weightLossGoalKgPerWeekValid = validateInput('weightLossGoalKgPerWeek', 0.1, 2.0, 'weightLossGoalKgPerWeekError', 'Weekly goal must be between 0.1 and 2.0 kg.'); var ageValid = validateInput('age', 1, 120, 'ageError', 'Please enter a valid age.'); var heightCmValid = validateInput('heightCm', 50, 250, 'heightCmError', 'Please enter a valid height.'); if (!currentWeightValid || !targetWeightValid || !weightLossGoalKgPerWeekValid || !ageValid || !heightCmValid) { document.getElementById('primary-result').innerText = '– kcal'; document.getElementById('tdeeResult').innerText = '– kcal'; document.getElementById('weeklyDeficitResult').innerText = '– kcal'; document.getElementById('timeToGoalResult').innerText = '– days'; updateTableValues('–', '–', '–', '–', '–', '–', '–', '–'); updateChart([], []); return; } var currentWeight = parseFloat(document.getElementById('currentWeight').value); var targetWeight = parseFloat(document.getElementById('targetWeight').value); var weightLossGoalKgPerWeek = parseFloat(document.getElementById('weightLossGoalKgPerWeek').value); var activityLevel = document.getElementById('activityLevel').value; var bmrMethod = document.getElementById('bmrMethod').value; var gender = document.getElementById('gender').value; var age = parseInt(document.getElementById('age').value); var heightCm = parseFloat(document.getElementById('heightCm').value); var bmr; if (bmrMethod === 'harris_benedict') { if (gender === 'male') { bmr = 88.362 + (13.397 * currentWeight) + (4.799 * heightCm) – (5.677 * age); } else { bmr = 447.593 + (9.247 * currentWeight) + (3.098 * heightCm) – (4.330 * age); } } else { // mifflin_st_jeor if (gender === 'male') { bmr = (10 * currentWeight) + (6.25 * heightCm) – (5 * age) + 5; } else { bmr = (10 * currentWeight) + (6.25 * heightCm) – (5 * age) – 161; } } var activityMultiplier; switch (activityLevel) { case 'sedentary': activityMultiplier = 1.2; break; case 'lightly_active': activityMultiplier = 1.375; break; case 'moderately_active': activityMultiplier = 1.55; break; case 'very_active': activityMultiplier = 1.725; break; case 'extra_active': activityMultiplier = 1.9; break; default: activityMultiplier = 1.2; } var tdee = bmr * activityMultiplier; var weightLossKg = currentWeight – targetWeight; var requiredWeeklyDeficit = weightLossGoalKgPerWeek * 7700; var dailyDeficit = requiredWeeklyDeficit / 7; var targetDailyIntake = tdee – dailyDeficit; var totalDeficitNeeded = weightLossKg * 7700; var timeToGoalDays = (weightLossKg > 0) ? (totalDeficitNeeded / dailyDeficit) : 0; // Ensure target intake is not unrealistically low if (targetDailyIntake 0) ? (totalDeficitNeeded / dailyDeficit) : 0; } else if (targetDailyIntake 0) ? (totalDeficitNeeded / dailyDeficit) : 0; } document.getElementById('primary-result').innerText = targetDailyIntake.toFixed(0) + ' kcal'; document.getElementById('tdeeResult').innerText = tdee.toFixed(0) + ' kcal'; document.getElementById('weeklyDeficitResult').innerText = requiredWeeklyDeficit.toFixed(0) + ' kcal'; document.getElementById('timeToGoalResult').innerText = timeToGoalDays.toFixed(0) + ' days'; updateTableValues( currentWeight.toFixed(1), targetWeight.toFixed(1), weightLossGoalKgPerWeek.toFixed(2), bmr.toFixed(0), tdee.toFixed(0), dailyDeficit.toFixed(0), requiredWeeklyDeficit.toFixed(0), timeToGoalDays.toFixed(0) ); updateChart(tdee, targetDailyIntake, timeToGoalDays); } function updateTableValues(currentW, targetW, goal, bmrVal, tdeeVal, dailyDef, weeklyDef, time) { document.getElementById('tableCurrentWeight').innerText = currentW; document.getElementById('tableTargetWeight').innerText = targetW; document.getElementById('tableWeeklyGoal').innerText = goal; document.getElementById('tableBMR').innerText = bmrVal === '–' ? '–' : bmrVal + ' kcal'; document.getElementById('tableTDEE').innerText = tdeeVal === '–' ? '–' : tdeeVal + ' kcal'; document.getElementById('tableDailyDeficit').innerText = dailyDef === '–' ? '–' : dailyDef + ' kcal/day'; document.getElementById('tableWeeklyDeficit').innerText = weeklyDef === '–' ? '–' : weeklyDef + ' kcal/week'; document.getElementById('tableTimeToGoal').innerText = time === '–' ? '–' : time + ' days'; } function updateChart(tdee, targetIntake, timeToGoal) { var ctx = document.getElementById('calorieBurnChart').getContext('2d'); // Clear previous chart if it exists if (chart) { chart.destroy(); } var labels = []; var tdeeData = []; var targetIntakeData = []; if (timeToGoal > 0 && tdee && targetIntake) { var days = Math.min(Math.max(30, parseInt(timeToGoal)), 180); // Show up to ~6 months of data, min 30 days var tdeeDecrementPerDay = 0; // For simplicity, assume TDEE is relatively stable var intakeDecrementPerDay = (tdee – targetIntake) / days; // Target intake decreases as TDEE decreases or goal is met for (var i = 0; i <= days; i++) { labels.push(i); tdeeData.push(tdee – (tdeeDecrementPerDay * i)); targetIntakeData.push(Math.max(targetIntake, 1200)); // Ensure intake doesn't go below a minimum } } else { // Default view if no goal or calculation failed labels.push(0, 1, 2, 3, 4, 5); tdeeData.push(tdee || 2000); targetIntakeData.push(tdee ? Math.max(tdee – 500, 1200) : 1500); } chart = new Chart(ctx, { type: 'line', data: { labels: labels.map(function(day) { return day + ' days'; }), datasets: [{ label: 'Estimated TDEE (kcal)', data: tdeeData, borderColor: 'var(–primary-color)', backgroundColor: 'rgba(0, 74, 153, 0.1)', fill: true, tension: 0.1 }, { label: 'Target Daily Intake (kcal)', data: targetIntakeData, borderColor: 'var(–success-color)', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: true, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: true, scales: { y: { beginAtZero: false, title: { display: true, text: 'Calories (kcal)' } }, x: { title: { display: true, text: 'Days to Goal' } } }, plugins: { tooltip: { mode: 'index', intersect: false, }, legend: { position: 'top', } } } }); } function copyResults() { var primaryResult = document.getElementById('primary-result').innerText; var tdeeResult = document.getElementById('tdeeResult').innerText; var weeklyDeficitResult = document.getElementById('weeklyDeficitResult').innerText; var timeToGoalResult = document.getElementById('timeToGoalResult').innerText; var currentWeight = document.getElementById('tableCurrentWeight').innerText; var targetWeight = document.getElementById('tableTargetWeight').innerText; var weeklyGoal = document.getElementById('tableWeeklyGoal').innerText; var bmr = document.getElementById('tableBMR').innerText; var tdee = document.getElementById('tableTDEE').innerText; var dailyDeficit = document.getElementById('tableDailyDeficit').innerText; var weeklyDeficit = document.getElementById('tableWeeklyDeficit').innerText; var time = document.getElementById('tableTimeToGoal').innerText; var copyText = `— Weight Loss Calculator Results —\n\n`; copyText += `Primary Target: ${primaryResult}\n`; copyText += `Estimated Daily Calorie Needs (TDEE): ${tdeeResult}\n`; copyText += `Required Weekly Calorie Deficit: ${weeklyDeficitResult}\n`; copyText += `Estimated Time to Reach Goal: ${timeToGoalResult}\n\n`; copyText += `— Detailed Summary —\n`; copyText += `Current Weight: ${currentWeight} kg\n`; copyText += `Target Weight: ${targetWeight} kg\n`; copyText += `Weekly Goal: ${weeklyGoal} kg/week\n`; copyText += `BMR: ${bmr}\n`; copyText += `TDEE: ${tdee}\n`; copyText += `Daily Deficit Required: ${dailyDeficit}\n`; copyText += `Weekly Deficit Required: ${weeklyDeficit}\n`; copyText += `Estimated Time to Goal: ${time}\n\n`; copyText += `Assumptions:\n`; copyText += `- Calculations based on ${document.getElementById('bmrMethod').options[document.getElementById('bmrMethod').selectedIndex].text} formula.\n`; copyText += `- Activity Level: ${document.getElementById('activityLevel').options[document.getElementById('activityLevel').selectedIndex].text}\n`; copyText += `- Approximately 7700 kcal deficit per 1 kg of fat loss.\n`; var textArea = document.createElement("textarea"); textArea.value = copyText; document.body.appendChild(textArea); textArea.select(); document.execCommand("copy"); textArea.remove(); alert("Results copied to clipboard!"); } function resetCalculator() { document.getElementById('currentWeight').value = '70'; document.getElementById('targetWeight').value = '65'; document.getElementById('weightLossGoalKgPerWeek').value = '0.5'; document.getElementById('activityLevel').value = 'moderately_active'; document.getElementById('bmrMethod').value = 'mifflin_st_jeor'; document.getElementById('gender').value = 'female'; document.getElementById('age').value = '30'; document.getElementById('heightCm').value = '165'; // Clear errors document.getElementById('currentWeightError').innerText = ''; document.getElementById('targetWeightError').innerText = ''; document.getElementById('weightLossGoalKgPerWeekError').innerText = ''; document.getElementById('ageError').innerText = ''; document.getElementById('heightCmError').innerText = ''; document.getElementById('currentWeightError').style.display = 'none'; document.getElementById('targetWeightError').style.display = 'none'; document.getElementById('weightLossGoalKgPerWeekError').style.display = 'none'; document.getElementById('ageError').style.display = 'none'; document.getElementById('heightCmError').style.display = 'none'; calculateCalories(); // Recalculate with default values } // Initial calculation on page load window.onload = function() { // Dynamically load Chart.js if not available if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js'; script.onload = function() { resetCalculator(); // Calculate after chart library is loaded }; document.head.appendChild(script); } else { resetCalculator(); // Calculate immediately if Chart.js is already present } };

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