Recommended Calories for Weight Loss Calculator

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Recommended Calories for Weight Loss Calculator

Determine your personalized daily calorie target for effective and sustainable weight loss.

Weight Loss Calorie Calculator

Enter your current age in years.
Male Female Select your gender for more accurate calculation.
Enter your current 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) Choose the option that best describes your typical weekly physical activity.
0.5 kg per week (Recommended) 1.0 kg per week (Aggressive) 0.25 kg per week (Gentle) Select your desired weekly weight loss rate. A 0.5 kg/week loss is generally considered safe and sustainable.

Your Results

Recommended Daily Calories for Weight Loss: kcal
Basal Metabolic Rate (BMR): kcal
Total Daily Energy Expenditure (TDEE): kcal
Calorie Deficit Needed: kcal per day
How it's calculated: First, your Basal Metabolic Rate (BMR) is estimated using the Mifflin-St Jeor equation. Then, your Total Daily Energy Expenditure (TDEE) is calculated by multiplying your BMR by your activity level factor. Finally, to achieve your desired weekly weight loss, a calorie deficit is subtracted from your TDEE. A deficit of 500 kcal/day typically leads to ~0.5 kg loss per week.

Calorie Intake vs. Expenditure Projection

This chart shows a projection of your daily calorie needs (TDEE) and your target weight loss intake over time, assuming consistent adherence.

Calorie Deficit and Weight Loss Timeline

Estimated Weight Loss Progression
Target Weekly Loss (kg) Daily Calorie Deficit (kcal) Estimated Time to Lose 5kg (Weeks) Estimated Time to Lose 10kg (Weeks)
Calculations will appear here.

The concept of **recommended calories for weight loss calculator** is central to understanding how to manage body weight effectively. It's not about starvation or extreme diets, but rather about creating a sustainable energy balance that promotes fat loss while preserving lean muscle mass. This calculator helps you pinpoint a personalized daily calorie target to achieve your weight loss goals safely and efficiently. Understanding your recommended calories for weight loss allows for informed dietary choices and a more structured approach to achieving a healthier physique.

Who should use it: Anyone looking to lose weight in a structured manner can benefit from using a recommended calories for weight loss calculator. This includes individuals aiming for gradual, sustainable fat loss, those preparing for specific events, or people seeking to improve their overall health and metabolism. It's particularly useful for those who have tried dieting before without consistent success and want a data-driven starting point. The calculator provides a scientifically-backed estimate, serving as a foundational tool for dietary planning.

Common misconceptions: A major misconception is that weight loss solely depends on drastically cutting calories, which can lead to muscle loss, nutrient deficiencies, and a slowed metabolism. Another is the belief that all calories are equal; nutrient-dense foods have different effects on satiety and health than calorie-dense, nutrient-poor options. Furthermore, many underestimate the impact of activity levels on overall energy expenditure. This calculator aims to provide a more holistic view by considering BMR, TDEE, and activity, offering recommended calories for weight loss that support a balanced approach.

{primary_keyword} Formula and Mathematical Explanation

The calculation of recommended calories for weight loss involves several key steps, primarily based on estimating your body's energy expenditure. The most common method utilizes the Mifflin-St Jeor equation to determine your Basal Metabolic Rate (BMR), followed by an adjustment for your activity level to find your Total Daily Energy Expenditure (TDEE). Finally, a calorie deficit is applied to TDEE to facilitate weight loss.

Step 1: Calculate Basal Metabolic Rate (BMR)

BMR is the number of calories your body burns at rest to maintain basic life-sustaining functions. 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

Step 2: Calculate Total Daily Energy Expenditure (TDEE)

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

TDEE = BMR × Activity Level Factor

Step 3: Determine Calorie Deficit for Weight Loss

To lose weight, you need to consume fewer calories than your TDEE, creating a calorie deficit. A deficit of approximately 3500 calories is generally needed to lose one pound (about 0.45 kg) of fat. For safer and more sustainable weight loss, a deficit of 500-1000 calories per day is often recommended, aiming for 0.5-1 kg loss per week.

Daily Calorie Target = TDEE – (Desired Weekly Loss × 7700 / 7)

(Note: 7700 kcal is an approximation for 1 kg of fat. We use 7700 here to calculate the daily deficit needed to achieve a specific weekly loss.)

For example, to lose 0.5 kg per week, you need a daily deficit of approximately (0.5 * 7700) / 7 ≈ 550 kcal.

Variables Table

Key Variables in Calorie Calculation
Variable Meaning Unit Typical Range
Age Number of years since birth. Affects metabolic rate. Years 1 – 120
Gender Biological sex. Influences body composition and BMR. Categorical (Male/Female) Male, Female
Weight Current body mass. A significant factor in BMR and TDEE. Kilograms (kg) 1 – 1000
Height Body stature. Also impacts BMR calculation. Centimeters (cm) 1 – 300
Activity Level Factor Multiplier reflecting average daily physical activity. Decimal (e.g., 1.2 – 1.9) 1.2 (Sedentary) to 1.9 (Extra Active)
Desired Weekly Loss Target rate of weight reduction. Kilograms (kg) per week 0.25 – 1.0
BMR Calories burned at rest. Kilocalories (kcal) Varies widely based on other factors
TDEE Total daily calories burned including activity. Kilocalories (kcal) Varies widely based on other factors
Calorie Deficit Reduction in daily calorie intake from TDEE for weight loss. Kilocalories (kcal) Calculated based on goal

Practical Examples (Real-World Use Cases)

Example 1: Sarah, a Moderately Active Woman

Sarah is a 35-year-old woman, weighs 70 kg, is 165 cm tall, and considers herself moderately active (exercises 3-5 times a week). She wants to lose 0.5 kg per week.

  • Inputs: Age: 35, Gender: Female, Weight: 70 kg, Height: 165 cm, Activity Level: 1.55, Desired Weekly Loss: 0.5 kg
  • BMR Calculation (Female): (10 * 70) + (6.25 * 165) – (5 * 35) – 161 = 700 + 1031.25 – 175 – 161 = 1395.25 kcal
  • TDEE Calculation: 1395.25 * 1.55 = 2162.64 kcal
  • Calorie Deficit for 0.5 kg/week: Approximately 550 kcal (0.5 * 7700 / 7)
  • Recommended Daily Calories: 2162.64 – 550 = 1612.64 kcal
  • Output: The calculator recommends Sarah consume approximately 1613 kcal per day to lose about 0.5 kg per week. This provides a sustainable target that accounts for her metabolism and activity level.

Example 2: Mark, a Sedentary Man

Mark is a 45-year-old man, weighs 90 kg, is 180 cm tall, and has a sedentary lifestyle (desk job, minimal exercise). He aims for a slightly more aggressive weight loss of 1 kg per week.

  • Inputs: Age: 45, Gender: Male, Weight: 90 kg, Height: 180 cm, Activity Level: 1.2, Desired Weekly Loss: 1.0 kg
  • BMR Calculation (Male): (10 * 90) + (6.25 * 180) – (5 * 45) + 5 = 900 + 1125 – 225 + 5 = 1805 kcal
  • TDEE Calculation: 1805 * 1.2 = 2166 kcal
  • Calorie Deficit for 1.0 kg/week: Approximately 1100 kcal (1.0 * 7700 / 7)
  • Recommended Daily Calories: 2166 – 1100 = 1066 kcal
  • Output: The calculator suggests Mark aim for about 1066 kcal per day. However, given this is quite low, the tool (and nutritionist advice) would emphasize caution. It might be more sustainable and healthier for Mark to aim for a 0.5 kg/week loss (approx. 1616 kcal/day) or increase his activity level to raise his TDEE. This highlights the importance of realistic goals and consulting professionals.

How to Use This {primary_keyword} Calculator

Using this recommended calories for weight loss calculator is straightforward and designed to give you a personalized calorie target quickly. Follow these simple steps:

  1. Enter Your Age: Input your current age in years. Age influences metabolic rate, with metabolism generally slowing down slightly over time.
  2. Select Your Gender: Choose 'Male' or 'Female'. Gender affects body composition and hormonal factors that influence BMR.
  3. Input Your Weight: Enter your current weight in kilograms (kg). This is a primary driver of your BMR and TDEE.
  4. Input Your Height: Enter your height in centimeters (cm). Height is another key factor in BMR calculations.
  5. Choose Your Activity Level: Select the option that best describes your typical weekly physical activity. This ranges from 'Sedentary' (little to no exercise) to 'Extra Active' (very hard exercise and a physically demanding job). This multiplier significantly impacts your TDEE.
  6. Set Your Weight Loss Goal: Choose your desired weekly weight loss rate (e.g., 0.5 kg/week, 1.0 kg/week). The calculator uses this to determine the necessary daily calorie deficit. A rate of 0.5 kg per week is generally recommended for sustainability and health.
  7. Click "Calculate Calories": Once all fields are filled, click this button. The calculator will instantly display your estimated BMR, TDEE, the required calorie deficit, and your primary recommended daily calorie intake for weight loss.
  8. Review Your Results: Pay close attention to the "Recommended Daily Calories for Weight Loss" highlighted result. Also, note your BMR and TDEE, which provide context for your calorie target. The "Calorie Deficit Needed" shows how much less you need to eat compared to your TDEE.
  9. Use the Chart and Table: Examine the projection chart and the weight loss timeline table for a visual understanding of your progress and how long it might take to reach certain milestones.
  10. Reset or Copy: Use the "Reset Inputs" button to clear the form and start over with different values. The "Copy Results" button allows you to easily save or share your calculated figures and assumptions.

Decision-making guidance: Use the calculated calorie target as a starting point. It's crucial to listen to your body. If you feel excessively fatigued, hungry, or experience other negative symptoms, your target might be too low, or you may need to adjust your macronutrient intake. Consult with a healthcare provider or registered dietitian for personalized advice, especially if you have underlying health conditions. The recommended calories for weight loss should align with a balanced diet and lifestyle.

Key Factors That Affect {primary_keyword} Results

While this calculator provides a scientifically grounded estimate, several real-world factors can influence your actual calorie needs and weight loss progress. Understanding these nuances is vital for successful and sustainable weight management.

  1. Metabolic Adaptation: As you lose weight, your BMR and TDEE naturally decrease because you have less body mass to maintain. Your body may also become more efficient, slightly reducing calorie expenditure. This means you might need to adjust your calorie intake downwards over time to continue losing weight. The calculator provides a snapshot; ongoing monitoring and adjustments are key.
  2. Body Composition: Muscle tissue burns more calories at rest than fat tissue. Someone with a higher percentage of lean muscle mass will have a higher BMR than someone of the same weight but with a lower muscle percentage. This calculator uses general formulas, but individual body composition can cause variations.
  3. Hormonal Fluctuations: Hormones like thyroid hormones, cortisol, and sex hormones significantly impact metabolism and appetite. Conditions like hypothyroidism or PCOS can alter metabolic rate, affecting the accuracy of standard calculations.
  4. Genetics: Individual genetic makeup plays a role in how efficiently your body burns calories, stores fat, and responds to different foods and exercise. Some people may naturally have a faster or slower metabolism due to their genes.
  5. Nutrient Timing and Food Choices: While total daily calories are paramount for weight loss, the types of food consumed matter for satiety, nutrient intake, and metabolic health. Protein, for example, has a higher thermic effect and promotes fullness more than fats or carbohydrates. This calculator focuses on total calories, not macronutrient breakdown.
  6. Sleep Quality and Stress Levels: Poor sleep and high stress levels can negatively impact hormones (like cortisol and ghrelin) that regulate appetite, cravings, and fat storage, potentially hindering weight loss efforts even if calorie intake is controlled.
  7. Medications: Certain medications can affect metabolism, appetite, or fluid retention, thereby influencing weight and calorie needs. Always consider potential medication side effects with your doctor.
  8. Digestive Efficiency: While typically minor, the actual number of calories absorbed from food can vary slightly based on individual digestive processes and gut microbiome health.

Frequently Asked Questions (FAQ)

Q1: Is a 1000 kcal/day diet safe for weight loss?

For most adults, consuming only 1000 kcal per day is generally not recommended without medical supervision. It's very difficult to meet all essential nutrient requirements at such a low intake, and it can lead to significant muscle loss, fatigue, and metabolic slowdown. This calculator aims for safe, sustainable deficits, typically resulting in higher calorie targets than 1000 kcal for most individuals. Always consult a healthcare professional before starting a very low-calorie diet.

Q2: How quickly can I expect to lose weight with this calculator's recommendation?

The calculator bases its target on achieving a specific weekly weight loss goal (e.g., 0.5 kg/week). A 0.5 kg weekly loss requires a daily deficit of about 550 kcal. Individual results can vary due to factors like adherence, metabolism, and activity level consistency. Expect gradual progress for sustainable results.

Q3: What should I do if I'm not losing weight despite following the recommended calories?

Several factors could be at play. Firstly, ensure you are accurately tracking your food intake and activity levels; hidden calories or overestimated exercise can disrupt the deficit. Secondly, your metabolism may have adapted, requiring a further reduction in calorie intake or an increase in activity. Consider consulting a dietitian or doctor to rule out underlying medical conditions or hormonal issues.

Q4: Does this calculator account for exercise calories burned?

Yes, indirectly. The 'Activity Level' input factor adjusts your Basal Metabolic Rate (BMR) to estimate your Total Daily Energy Expenditure (TDEE), which includes calories burned through planned exercise and general daily movement. However, accurately tracking exercise calories burned is complex, and it's often advisable to not rely heavily on exercise for creating your deficit, but rather focus on consistent dietary intake.

Q5: Can I eat more on days I exercise heavily?

Some people find success with calorie cycling, consuming slightly more calories on heavy exercise days and fewer on rest days, while maintaining the same weekly average. However, for simplicity and consistency, sticking to the calculated daily target is often easiest for beginners. If you choose to cycle calories, ensure your weekly average deficit is maintained.

Q6: How does muscle gain affect weight loss calculations?

Muscle is denser than fat and burns more calories at rest. If you are engaging in strength training, you might gain muscle while losing fat. This can mean the number on the scale changes slowly, or even stays the same, even though your body composition is improving. Focus on measurements, how your clothes fit, and your energy levels, in addition to the scale.

Q7: Is the Mifflin-St Jeor equation the only way to calculate BMR?

No, other formulas exist, such as the original Harris-Benedict equation or Katch-McArdle (which requires body fat percentage). Mifflin-St Jeor is widely used because it's considered one of the most accurate for the general population without requiring body fat measurement. Our calculator uses this widely accepted standard.

Q8: Can I use this calculator for weight gain?

This specific calculator is designed for recommended calories for weight loss. To gain weight, you would need to create a calorie surplus (consume more calories than your TDEE). A separate calculator for weight gain would typically add calories to your TDEE instead of subtracting them.

© 2023 Your Website Name. All rights reserved. This calculator provides estimates for informational purposes only. Consult with a healthcare professional for personalized advice.

function calculateWeightLossCalories() { var age = parseFloat(document.getElementById("age").value); var gender = document.getElementById("gender").value; var weight = parseFloat(document.getElementById("weight").value); var height = parseFloat(document.getElementById("height").value); var activityLevel = parseFloat(document.getElementById("activityLevel").value); var weightLossGoal = parseFloat(document.getElementById("weightLossGoal").value); var ageError = document.getElementById("ageError"); var weightError = document.getElementById("weightError"); var heightError = document.getElementById("heightError"); // Reset errors ageError.style.display = "none"; weightError.style.display = "none"; heightError.style.display = "none"; var isValid = true; if (isNaN(age) || age 120) { ageError.textContent = "Please enter a valid age between 1 and 120."; ageError.style.display = "block"; isValid = false; } if (isNaN(weight) || weight 1000) { weightError.textContent = "Please enter a valid weight between 1 and 1000 kg."; weightError.style.display = "block"; isValid = false; } if (isNaN(height) || height 300) { heightError.textContent = "Please enter a valid height between 1 and 300 cm."; heightError.style.display = "block"; isValid = false; } if (!isValid) { // Clear results if inputs are invalid document.querySelector('.bmr-value').textContent = '–'; document.querySelector('.tdee-value').textContent = '–'; document.querySelector('.deficit-value').textContent = '–'; document.querySelector('#primaryResult .value').textContent = '–'; // Clear table and chart document.getElementById("weightLossTableBody").innerHTML = 'Calculations will appear here.'; clearChart(); return; } // Calculate BMR using Mifflin-St Jeor Equation var bmr; if (gender === "male") { bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5; } else { // female bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161; } // Calculate TDEE var tdee = bmr * activityLevel; // Calculate calorie deficit needed for weight loss // Approximate calories in 1 kg of fat: 7700 kcal var dailyDeficit = (weightLossGoal * 7700) / 7; var targetCalories = tdee – dailyDeficit; // Ensure target calories are not unrealistically low var minSafeCalories = 1200; // General guideline, can be adjusted if (targetCalories < minSafeCalories) { targetCalories = minSafeCalories; dailyDeficit = tdee – targetCalories; // Recalculate deficit based on minimum // Optionally, warn the user if the target is very low console.warn("Calculated target calories are very low. Adjusted to " + minSafeCalories + " kcal. Consider consulting a professional."); } // Display results document.querySelector('.bmr-value').textContent = bmr.toFixed(0); document.querySelector('.tdee-value').textContent = tdee.toFixed(0); document.querySelector('.deficit-value').textContent = dailyDeficit.toFixed(0); document.querySelector('#primaryResult .value').textContent = targetCalories.toFixed(0); // Update table updateWeightLossTable(dailyDeficit); // Update chart updateCalorieProjectionChart(tdee, targetCalories); } function updateWeightLossTable(dailyDeficit) { var tableBody = document.getElementById("weightLossTableBody"); tableBody.innerHTML = ''; // Clear previous data var weeklyLossOptions = [0.25, 0.5, 1.0]; // kg per week var kcalPerKgFat = 7700; weeklyLossOptions.forEach(function(goal) { var currentDailyDeficit = (goal * kcalPerKgFat) / 7; var timeToLose5kg = (5 * kcalPerKgFat) / currentDailyDeficit; var timeToLose10kg = (10 * kcalPerKgFat) / currentDailyDeficit; var row = tableBody.insertRow(); row.insertCell(0).textContent = goal.toFixed(2); row.insertCell(1).textContent = currentDailyDeficit.toFixed(0); row.insertCell(2).textContent = isNaN(timeToLose5kg) ? "N/A" : timeToLose5kg.toFixed(1) + " weeks"; row.insertCell(3).textContent = isNaN(timeToLose10kg) ? "N/A" : timeToLose10kg.toFixed(1) + " weeks"; }); } var chartInstance = null; // Global variable to hold chart instance function updateCalorieProjectionChart(tdee, targetCalories) { var ctx = document.getElementById('calorieProjectionChart').getContext('2d'); // Destroy previous chart instance if it exists if (chartInstance) { chartInstance.destroy(); } var labels = []; var tdeeData = []; var targetData = []; var numDays = 30; // Project for 30 days for (var i = 0; i < numDays; i++) { labels.push("Day " + (i + 1)); tdeeData.push(tdee); targetData.push(targetCalories); } chartInstance = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: [{ label: 'Estimated TDEE (kcal)', data: tdeeData, borderColor: 'rgb(0, 74, 153)', backgroundColor: 'rgba(0, 74, 153, 0.2)', fill: false, tension: 0.1 }, { label: 'Target Weight Loss Intake (kcal)', data: targetData, borderColor: 'rgb(40, 167, 69)', backgroundColor: 'rgba(40, 167, 69, 0.2)', fill: false, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: true, title: { display: true, text: 'Calories (kcal)' } }, x: { title: { display: true, text: 'Time' } } }, plugins: { legend: { position: 'top', }, title: { display: true, text: 'Daily Calorie Projection Over 30 Days' } } } }); } function clearChart() { var ctx = document.getElementById('calorieProjectionChart').getContext('2d'); if (chartInstance) { chartInstance.destroy(); chartInstance = null; } // Optionally clear canvas drawing if needed, but destroy() usually suffices ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height); } function resetCalculator() { document.getElementById("age").value = 30; document.getElementById("gender").value = "male"; document.getElementById("weight").value = 70; document.getElementById("height").value = 175; document.getElementById("activityLevel").value = 1.375; // Default to Lightly Active document.getElementById("weightLossGoal").value = 0.5; // Default to 0.5 kg/week // Clear errors document.getElementById("ageError").style.display = "none"; document.getElementById("weightError").style.display = "none"; document.getElementById("heightError").style.display = "none"; // Clear results document.querySelector('.bmr-value').textContent = '–'; document.querySelector('.tdee-value').textContent = '–'; document.querySelector('.deficit-value').textContent = '–'; document.querySelector('#primaryResult .value').textContent = '–'; // Clear table and chart document.getElementById("weightLossTableBody").innerHTML = 'Calculations will appear here.'; clearChart(); } function copyResults() { var bmr = document.querySelector('.bmr-value').textContent; var tdee = document.querySelector('.tdee-value').textContent; var deficit = document.querySelector('.deficit-value').textContent; var targetCalories = document.querySelector('#primaryResult .value').textContent; if (targetCalories === '–') { alert("No results to copy yet. Please calculate first."); return; } var resultText = "— Recommended Calories for Weight Loss —\n\n"; resultText += "Primary Target: " + targetCalories + " kcal per day\n"; resultText += "Basal Metabolic Rate (BMR): " + bmr + " kcal\n"; resultText += "Total Daily Energy Expenditure (TDEE): " + tdee + " kcal\n"; resultText += "Daily Calorie Deficit: " + deficit + " kcal\n\n"; resultText += "Assumptions:\n"; resultText += "Gender: " + document.getElementById("gender").options[document.getElementById("gender").selectedIndex].text + "\n"; resultText += "Activity Level: " + document.getElementById("activityLevel").options[document.getElementById("activityLevel").selectedIndex].text + "\n"; resultText += "Desired Weekly Loss: " + document.getElementById("weightLossGoal").options[document.getElementById("weightLossGoal").selectedIndex].text + "\n"; // Using a temporary textarea to leverage the browser's clipboard API var textArea = document.createElement("textarea"); textArea.value = resultText; textArea.style.position = "fixed"; // Avoid scrolling to bottom textArea.style.left = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied to clipboard!' : 'Failed to copy results.'; alert(msg); } catch (err) { alert('Oops, unable to copy'); } document.body.removeChild(textArea); } // Add event listeners document.getElementById("calculateBtn").addEventListener("click", calculateWeightLossCalories); document.getElementById("resetBtn").addEventListener("click", resetCalculator); document.getElementById("copyBtn").addEventListener("click", copyResults); // Initial calculation on page load if default values are set // calculateWeightLossCalories(); // Uncomment if you want it to calculate on load // FAQ toggle functionality function toggleFaq(element) { var answer = element.nextElementSibling; if (answer.style.display === "block") { answer.style.display = "none"; } else { answer.style.display = "block"; } } // Dynamically load Chart.js if it's not already loaded // IMPORTANT: For a single file HTML, Chart.js would typically be included via CDN in the or before the script. // This placeholder assumes Chart.js is available globally. In a real implementation, add: // // to the section. if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js'; document.head.appendChild(script); // Wait for script to load before enabling chart functionality or recalculating script.onload = function() { console.log("Chart.js loaded."); // If initial calculation on load is desired and Chart.js is required: // calculateWeightLossCalories(); }; } else { // If Chart.js is already loaded, ensure initial calculation happens if needed // calculateWeightLossCalories(); // Uncomment if you want it to calculate on load }

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