How to Calculate Target Calories for Weight Loss

How to Calculate Target Calories for Weight Loss | Your Expert Guide :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –border-color: #dee2e6; –white: #fff; –shadow: 0 2px 5px rgba(0,0,0,0.1); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; line-height: 1.6; background-color: var(–background-color); color: var(–text-color); margin: 0; padding: 0; } .container { max-width: 1000px; margin: 20px auto; padding: 20px; background-color: var(–white); border-radius: 8px; box-shadow: var(–shadow); } header { background-color: var(–primary-color); color: var(–white); padding: 20px 0; text-align: center; margin-bottom: 20px; border-radius: 8px 8px 0 0; } header h1 { margin: 0; font-size: 2.5em; } h2, h3 { color: var(–primary-color); margin-top: 1.5em; margin-bottom: 0.8em; } .calculator-section { background-color: var(–white); padding: 25px; border-radius: 8px; box-shadow: var(–shadow); margin-bottom: 30px; } .calculator-section h2 { text-align: center; margin-top: 0; margin-bottom: 20px; } .input-group { margin-bottom: 20px; text-align: left; } .input-group label { display: block; margin-bottom: 8px; font-weight: bold; color: var(–primary-color); } .input-group input[type="number"], .input-group select { width: calc(100% – 22px); padding: 12px; border: 1px solid var(–border-color); border-radius: 4px; font-size: 1em; box-sizing: border-box; } .input-group input[type="number"]:focus, .input-group select:focus { outline: none; border-color: var(–primary-color); box-shadow: 0 0 0 2px rgba(0, 74, 153, 0.2); } .input-group .helper-text { font-size: 0.85em; color: #6c757d; margin-top: 5px; display: block; } .error-message { color: red; font-size: 0.85em; margin-top: 5px; display: none; /* Hidden by default */ } .buttons { display: flex; justify-content: space-between; gap: 10px; margin-top: 25px; } button { background-color: var(–primary-color); color: var(–white); border: none; padding: 12px 20px; border-radius: 4px; cursor: pointer; font-size: 1em; transition: background-color 0.3s ease; flex-grow: 1; } button.reset { background-color: #6c757d; } button:hover { background-color: #003366; } button.reset:hover { background-color: #5a6268; } #result { background-color: var(–success-color); color: var(–white); padding: 20px; margin-top: 25px; border-radius: 4px; text-align: center; font-size: 1.5em; font-weight: bold; box-shadow: inset 0 0 10px rgba(0,0,0,0.2); } #result span { font-size: 1.2em; display: block; margin-top: 5px; } .intermediate-results, .formula-explanation { background-color: #e9ecef; padding: 15px; margin-top: 20px; border-radius: 4px; font-size: 0.95em; color: #495057; } .intermediate-results h3, .formula-explanation h3 { margin-top: 0; color: var(–primary-color); font-size: 1.2em; } .intermediate-results ul { list-style: none; padding: 0; margin: 0; } .intermediate-results li { margin-bottom: 8px; display: flex; justify-content: space-between; } .intermediate-results li span:first-child { font-weight: bold; color: #343a40; } .chart-container { background-color: var(–white); padding: 25px; border-radius: 8px; box-shadow: var(–shadow); margin-top: 30px; text-align: center; } canvas { max-width: 100%; height: auto; } .chart-caption { font-size: 0.9em; color: #6c757d; margin-top: 10px; } table { width: 100%; border-collapse: collapse; margin-top: 25px; } th, td { padding: 12px; text-align: left; border: 1px solid var(–border-color); } th { background-color: var(–primary-color); color: var(–white); } td { background-color: var(–white); } tr:nth-child(even) td { background-color: #f2f2f2; } .article-content { background-color: var(–white); padding: 25px; border-radius: 8px; box-shadow: var(–shadow); margin-top: 30px; } .article-content p, .article-content ul, .article-content ol { margin-bottom: 1.5em; } .article-content a { color: var(–primary-color); text-decoration: none; } .article-content a:hover { text-decoration: underline; } .faq-item { margin-bottom: 1.5em; border-left: 3px solid var(–primary-color); padding-left: 15px; } .faq-item h3 { margin-bottom: 0.5em; font-size: 1.1em; } .related-tools ul { list-style: none; padding: 0; } .related-tools li { margin-bottom: 10px; } .related-tools li strong { display: block; margin-bottom: 3px; } .hidden { display: none !important; } .show { display: block !important; }

How to Calculate Target Calories for Weight Loss

Your Essential Guide to Personalized Calorie Needs

Weight Loss Calorie Calculator

Estimate your daily calorie target for effective and sustainable weight loss. Enter your details below.

Enter your current weight in pounds (lbs) or kilograms (kg). Please enter a valid positive number for weight.
Enter your height in inches (in) or centimeters (cm). Please enter a valid positive number for height.
Enter your age in years. Please enter a valid positive number for age.
Male Female Select your gender for a more accurate calculation.
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 a week) Extra Active (very hard exercise/sports & physical job) Choose the option that best describes your daily physical activity.
How many pounds (lbs) or kilograms (kg) you aim to lose per week. Please enter a valid number between 0.5 and 2 (or 0.25 to 1 kg).
Imperial (lbs, inches) Metric (kg, cm) Select your preferred unit system.
Target Daily Calories: kcal

Key Calculations

  • Basal Metabolic Rate (BMR): kcal
  • Total Daily Energy Expenditure (TDEE): kcal
  • Calorie Deficit for Weight Loss: kcal

Formula Used: We first calculate your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation. Then, we multiply BMR by your activity factor to get your Total Daily Energy Expenditure (TDEE). Finally, we subtract a calorie deficit based on your desired weekly weight loss from your TDEE to determine your target daily calories.

Calorie Breakdown Over Time

Estimated daily calorie targets for different weekly weight loss rates.

Metabolic Rate Factors
Activity Level Activity Factor Description
Sedentary 1.2 Little to no exercise
Lightly Active 1.375 Light exercise/sports 1-3 days/week
Moderately Active 1.55 Moderate exercise/sports 3-5 days/week
Very Active 1.725 Hard exercise/sports 6-7 days a week
Extra Active 1.9 Very hard exercise/sports & physical job

What is Target Calorie Calculation for Weight Loss?

{primary_keyword} is the process of determining the specific number of calories you should consume daily to achieve a sustainable rate of weight loss. It's not about drastically cutting calories, but rather establishing a personalized, calorie deficit that aligns with your body's unique metabolic needs and activity levels. Understanding your target calories is a cornerstone of any successful weight management plan, moving beyond generic advice to provide actionable, data-driven guidance.

Who Should Use It: Anyone looking to lose weight in a healthy and controlled manner can benefit from calculating their target calories. This includes individuals aiming for gradual fat loss, those preparing for an event, or people who have struggled with yo-yo dieting and want a more sustainable approach. It's particularly useful for understanding how lifestyle choices, such as exercise frequency and intensity, impact your overall energy balance.

Common Misconceptions: A frequent misconception is that all calories are equal, regardless of source. While the calculation focuses on quantity, nutritional quality is vital for health and satiety. Another myth is that extreme calorie restriction is the fastest way to lose weight. In reality, this can slow metabolism, lead to muscle loss, and be unsustainable. This calculator helps find a moderate deficit for healthy weight loss.

{primary_keyword} Formula and Mathematical Explanation

The calculation of target calories for weight loss primarily involves estimating your Total Daily Energy Expenditure (TDEE) and then creating a deficit from that number. The most common method uses the Mifflin-St Jeor equation to estimate Basal Metabolic Rate (BMR), which is the number of calories your body burns at rest.

Step 1: Calculate Basal Metabolic Rate (BMR)

The Mifflin-St Jeor equation is widely considered more accurate than older formulas like Harris-Benedict:

  • 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

If using pounds and inches, convert them first:

  • Weight in kg = Weight in lbs × 0.453592
  • Height in cm = Height in inches × 2.54

Step 2: Calculate Total Daily Energy Expenditure (TDEE)

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

TDEE = BMR × Activity Factor

Step 3: Determine Calorie Deficit for Weight Loss

A common guideline is that a deficit of 3,500 calories results in approximately 1 pound of fat loss. To lose a specific amount of weight per week, you create a corresponding daily deficit:

  • If losing 1 lb/week: Daily Deficit = 3500 calories / 7 days = 500 calories
  • If losing 2 lbs/week: Daily Deficit = (3500 × 2) calories / 7 days = 1000 calories

More precisely, for metric units:

  • 1 kg of fat is approximately 7700 calories.
  • If losing 0.5 kg/week: Daily Deficit = 7700 × 0.5 / 7 = 550 calories
  • If losing 1 kg/week: Daily Deficit = 7700 × 1 / 7 = 1100 calories

The calculator adjusts this deficit based on the chosen `Desired Weekly Weight Loss` input.

Step 4: Calculate Target Daily Calories

Subtract the determined daily deficit from your TDEE:

Target Daily Calories = TDEE – Daily Deficit

Variables Table

Variable Meaning Unit Typical Range
Weight Current body weight lbs or kg 100 – 500+
Height Body height inches or cm 50 – 200+
Age Age in years Years 18 – 90+
Gender Biological sex Male/Female N/A
Activity Factor Multiplier for daily activity level Decimal (e.g., 1.2 – 1.9) 1.2 – 1.9
Desired Weekly Weight Loss Target weight loss rate per week lbs or kg 0.5 – 2 (lbs) or 0.25 – 1 (kg)
BMR Calories burned at rest kcal/day 1000 – 2500+
TDEE Total calories burned daily including activity kcal/day 1500 – 4000+
Calorie Deficit Calories to subtract for weight loss kcal/day 300 – 1100+
Target Daily Calories Recommended daily calorie intake for weight loss kcal/day 1200 – 2500+

Practical Examples (Real-World Use Cases)

Example 1: Sarah, aiming for moderate weight loss

Sarah is a 30-year-old female, weighing 160 lbs and standing 65 inches tall. She describes herself as moderately active (exercises 3-5 days a week) and wants to lose 1 lb per week. She uses the Imperial unit system.

  • Inputs: Weight: 160 lbs, Height: 65 in, Age: 30, Gender: Female, Activity Level: Moderately Active (1.55), Desired Weekly Weight Loss: 1 lb, Unit System: Imperial
  • Calculations:
    • Weight in kg: 160 * 0.453592 = 72.57 kg
    • Height in cm: 65 * 2.54 = 165.1 cm
    • BMR = (10 * 72.57) + (6.25 * 165.1) – (5 * 30) – 161 = 725.7 + 1031.875 – 150 – 161 = 1446.575 kcal (approx. 1447 kcal)
    • TDEE = 1447 * 1.55 = 2242.85 kcal (approx. 2243 kcal)
    • Daily Deficit for 1 lb/week = 500 kcal
    • Target Daily Calories = 2243 – 500 = 1743 kcal
  • Result: Sarah's target daily calorie intake for losing 1 lb per week is approximately 1743 kcal.
  • Interpretation: This provides Sarah with a clear daily calorie goal to aim for. She can now plan meals and snacks to stay around this number, focusing on nutrient-dense foods to feel full and satisfied.

Example 2: David, aiming for faster weight loss

David is a 45-year-old male, weighing 220 lbs and 72 inches tall. He works a physically demanding job and exercises vigorously 6-7 days a week (Extra Active). He wants to lose 2 lbs per week and prefers Metric units.

  • Inputs: Weight: 220 lbs, Height: 72 in, Age: 45, Gender: Male, Activity Level: Extra Active (1.9), Desired Weekly Weight Loss: 2 lbs, Unit System: Metric
  • Calculations:
    • Weight in kg: 220 * 0.453592 = 99.79 kg (approx. 99.8 kg)
    • Height in cm: 72 * 2.54 = 182.88 cm (approx. 183 cm)
    • BMR = (10 * 99.8) + (6.25 * 183) – (5 * 45) + 5 = 998 + 1143.75 – 225 + 5 = 1921.75 kcal (approx. 1922 kcal)
    • TDEE = 1922 * 1.9 = 3651.8 kcal (approx. 3652 kcal)
    • Daily Deficit for 2 lbs/week = 1000 kcal
    • Target Daily Calories = 3652 – 1000 = 2652 kcal
  • Result: David's target daily calorie intake for losing 2 lbs per week is approximately 2652 kcal.
  • Interpretation: Given David's high TDEE due to his intense activity level, he can afford a larger deficit and still consume a substantial amount of calories. This target allows for significant weight loss while potentially supporting high energy demands. It's crucial for him to ensure adequate protein intake to preserve muscle mass.

How to Use This {primary_keyword} Calculator

Using our calculator is straightforward and designed to give you a personalized calorie target quickly. Follow these simple steps:

  1. Enter Your Details: Input your current weight, height, age, and select your gender. Ensure you choose the correct unit system (Imperial or Metric) that you are most comfortable with.
  2. Select Activity Level: Choose the option that best reflects your average daily physical activity. Be honest with yourself; overestimating can lead to an inaccurate TDEE and potentially hinder weight loss. Refer to the table provided for descriptions.
  3. Set Your Goal: Input how many pounds (or kilograms) you aim to lose per week. For sustainable and healthy weight loss, aiming for 1-2 lbs (0.5-1 kg) per week is generally recommended.
  4. Calculate: Click the "Calculate Target Calories" button.

How to Read Results:

  • Primary Result (Target Daily Calories): This is your main goal – the estimated number of calories you should consume each day to achieve your desired weekly weight loss rate.
  • Intermediate Values:
    • BMR: Your resting metabolic rate.
    • TDEE: Your total daily energy expenditure, including activity.
    • Calorie Deficit: The number of calories you need to subtract from your TDEE daily.

Decision-Making Guidance: Use your target daily calories as a guideline. Focus on consuming nutrient-dense foods to feel satiated. Monitor your progress and adjust your intake or activity level if needed. If you're not losing weight, you may need to slightly decrease your calorie intake or increase your activity. Conversely, if you feel excessively fatigued or are losing weight too rapidly, you might need to increase your intake slightly.

Key Factors That Affect {primary_keyword} Results

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

  1. Body Composition: Muscle tissue burns more calories at rest than fat tissue. Individuals with higher muscle mass may have a higher BMR, thus a higher TDEE. The basic calculation doesn't differentiate between fat and muscle mass.
  2. Metabolic Adaptations: Over time, as you lose weight, your BMR and TDEE can decrease. This is because a smaller body requires less energy. Weight loss plateaus can occur due to these adaptations.
  3. Hormonal Influences: Hormones like thyroid hormones, cortisol, and insulin play a significant role in metabolism. Conditions like hypothyroidism can lower BMR, while other hormonal imbalances might affect appetite and fat storage.
  4. Genetics: Your genetic makeup can influence your metabolic rate, appetite regulation, and how your body stores fat, contributing to individual variations in calorie needs.
  5. Medications: Certain medications, such as steroids or some antidepressants, can affect metabolism, appetite, and weight, potentially altering your calorie requirements.
  6. Digestive Efficiency: While often overlooked, the thermic effect of food (TEF) – the calories burned during digestion – can vary slightly based on macronutrient composition. However, this calculator uses standard activity multipliers.
  7. Nutrient Timing and Macronutrient Distribution: While total daily calories are paramount for weight loss, the *types* of calories consumed (protein, carbs, fats) and their distribution throughout the day can impact satiety, muscle preservation, and overall adherence to a diet plan.
  8. Sleep Quality and Stress Levels: Poor sleep and high stress can disrupt hormones that regulate appetite (ghrelin and leptin) and cortisol levels, potentially increasing cravings and promoting fat storage, even if calorie intake is controlled.

Frequently Asked Questions (FAQ)

Can I lose more than 2 lbs per week?

While the calculator allows for up to 2 lbs (or 1 kg) per week, losing more than this is generally not recommended for sustainable fat loss. Rapid weight loss often involves significant muscle loss and can be detrimental to health. Consult a healthcare professional before attempting rapid weight loss.

What if my TDEE is very low?

If your calculated TDEE is very low, it might indicate a need to re-evaluate your activity level or consider underlying health conditions. Extremely low calorie intakes (e.g., below 1200 kcal for women or 1500 kcal for men) can be unsustainable and unhealthy without medical supervision.

Does the calculator account for exercise calories burned?

The 'Activity Level' input factor in the calculator accounts for *average* daily activity and planned exercise. It's an estimate. If you engage in intense, long workouts, you might burn more calories than the factor suggests. However, it's generally advised not to eat back *all* exercise calories, as activity monitors can overestimate calorie burn.

How accurate is the Mifflin-St Jeor equation?

The Mifflin-St Jeor equation is considered one of the most accurate BMR prediction formulas available for general populations. However, it's still an estimation. Individual metabolic rates can vary due to genetics, body composition, and other factors not included in standard formulas.

Should I eat exactly my target calories every day?

The target calorie number is a guideline. Consistency over time is key. It's okay to be slightly over or under on any given day, as long as your average intake over the week aligns with your goal. Focus on overall patterns rather than daily perfection.

What if I have a medical condition affecting my weight?

This calculator is for general informational purposes and is not a substitute for professional medical advice. If you have conditions like thyroid issues, PCOS, diabetes, or are taking medications that affect weight, consult your doctor or a registered dietitian for personalized guidance.

How often should I recalculate my target calories?

As you lose weight, your BMR and TDEE decrease. It's advisable to recalculate your target calories every 10-15 lbs of weight lost, or if your activity level changes significantly, to ensure your goals remain aligned with your changing body.

What does 'Sedentary' activity level mean?

A sedentary activity level typically means you have an office job or don't engage in regular physical activity. Your daily calorie needs are primarily based on your BMR plus a small amount for basic daily movements like walking around the house or short commutes.

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1200 : 1500; if (targetCalories < minSafeCalories) { targetCalories = minSafeCalories; // Optionally, warn the user that the target was capped // document.getElementById('warningMessage').style.display = 'block'; // Add a warning element if needed } // Display results document.getElementById('targetCalories').textContent = targetCalories.toFixed(0); document.getElementById('bmrValue').textContent = bmr.toFixed(0); document.getElementById('tdeeValue').textContent = tdee.toFixed(0); document.getElementById('deficitValue').textContent = deficitValue.toFixed(0); // Update chart updateChart(tdee, targetCalories, deficitValue); } function resetForm() { document.getElementById('weight').value = ''; document.getElementById('height').value = ''; document.getElementById('age').value = ''; document.getElementById('gender').value = 'male'; document.getElementById('activityLevel').value = '1.55'; // Moderately Active default document.getElementById('weightLossGoal').value = '1'; document.getElementById('unitSystem').value = 'imperial'; document.getElementById('targetCalories').textContent = '–'; document.getElementById('bmrValue').textContent = '–'; document.getElementById('tdeeValue').textContent = '–'; document.getElementById('deficitValue').textContent = '–'; // Clear errors var errorElements = document.getElementsByClassName('error-message'); for (var i = 0; i < errorElements.length; i++) { errorElements[i].style.display = 'none'; } // Clear chart if (chartInstance) { chartInstance.destroy(); chartInstance = null; } } function copyResults() { var targetCalories = document.getElementById('targetCalories').textContent; var bmrValue = document.getElementById('bmrValue').textContent; var tdeeValue = document.getElementById('tdeeValue').textContent; var deficitValue = document.getElementById('deficitValue').textContent; if (targetCalories === '–') { alert("No results to copy yet. Please calculate first."); return; } var resultText = "— Weight Loss Calorie Calculation Results —\n\n"; resultText += "Target Daily Calories: " + targetCalories + " kcal\n"; resultText += "Basal Metabolic Rate (BMR): " + bmrValue + " kcal\n"; resultText += "Total Daily Energy Expenditure (TDEE): " + tdeeValue + " kcal\n"; resultText += "Calorie Deficit for Weight Loss: " + deficitValue + " kcal\n\n"; resultText += "Key Assumptions:\n"; resultText += "- Calculations based on Mifflin-St Jeor equation.\n"; resultText += "- Deficit calculated for desired weekly loss rate.\n"; resultText += "- Target calories adjusted to a minimum safe level if calculation falls below.\n"; // Create a temporary textarea element to copy text var textArea = document.createElement("textarea"); textArea.value = resultText; textArea.style.position = "fixed"; // Avoid scrolling to bottom of page in MS Edge. textArea.style.top = 0; textArea.style.left = 0; textArea.style.width = '2em'; textArea.style.height = '2em'; textArea.style.padding = '0'; textArea.style.border = 'none'; textArea.style.outline = 'none'; textArea.style.boxShadow = 'none'; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied to clipboard!' : 'Copying text command was unsuccessful'; // alert(msg); // Use a more subtle notification if possible // For simplicity, using alert here. In a real app, use a toast/snackbar. } catch (err) { // alert('Oops, unable to copy'); } document.body.removeChild(textArea); } // Initial calculation on page load if fields have default values // Or just var user click the button // calculateCalories(); // Add event listeners for real-time updates (optional, button click is primary) document.getElementById('weight').addEventListener('input', calculateCalories); document.getElementById('height').addEventListener('input', calculateCalories); document.getElementById('age').addEventListener('input', calculateCalories); document.getElementById('gender').addEventListener('change', calculateCalories); document.getElementById('activityLevel').addEventListener('change', calculateCalories); document.getElementById('weightLossGoal').addEventListener('input', calculateCalories); document.getElementById('unitSystem').addEventListener('change', calculateCalories); // Dummy Chart.js library inclusion for the example to work standalone // In a real WordPress setup, you would enqueue this properly. var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js@3.9.1/dist/chart.min.js'; script.onload = function() { console.log('Chart.js loaded.'); // Initial calculation after chart library is loaded document.addEventListener('DOMContentLoaded', function() { calculateCalories(); // Perform initial calculation }); }; document.head.appendChild(script);

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