Calculate Calories to Eat to Lose Weight

Calculate Calories to Eat to Lose Weight | Your Go-To Calculator :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –white: #fff; –border-color: #ddd; –shadow-color: rgba(0, 0, 0, 0.1); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: var(–background-color); color: var(–text-color); line-height: 1.6; margin: 0; padding: 0; display: flex; flex-direction: column; align-items: center; } .container { width: 100%; max-width: 1000px; margin: 20px auto; padding: 20px; background-color: var(–white); box-shadow: 0 4px 8px var(–shadow-color); border-radius: 8px; box-sizing: border-box; } h1, h2, h3 { color: var(–primary-color); text-align: center; } h1 { margin-bottom: 0.5em; font-size: 2.5em; } h2 { margin-top: 1.5em; margin-bottom: 1em; font-size: 2em; } h3 { margin-top: 1em; margin-bottom: 0.7em; font-size: 1.5em; } .calc-header { background-color: var(–primary-color); color: var(–white); padding: 20px; border-radius: 8px 8px 0 0; margin: -20px -20px 20px -20px; } .calc-header h2 { color: var(–white); margin: 0; font-size: 2em; } .loan-calc-container { margin-bottom: 30px; padding: 20px; border: 1px solid var(–border-color); border-radius: 8px; background-color: var(–background-color); } .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); /* Account for padding and border */ padding: 10px; border: 1px solid var(–border-color); border-radius: 4px; font-size: 1em; box-sizing: border-box; } .input-group select { cursor: pointer; } .input-group .helper-text { font-size: 0.85em; color: #666; margin-top: 5px; display: block; } .input-group .error-message { color: red; font-size: 0.8em; margin-top: 5px; display: none; /* Hidden by default */ height: 1.2em; /* Reserve space */ } .error-message.visible { display: block; } button { background-color: var(–primary-color); color: var(–white); border: none; padding: 12px 25px; border-radius: 5px; cursor: pointer; font-size: 1.1em; margin: 5px; transition: background-color 0.3s ease; } button:hover { background-color: #003366; } button.reset-button { background-color: #6c757d; } button.reset-button:hover { background-color: #5a6268; } button.copy-button { background-color: var(–success-color); } button.copy-button:hover { background-color: #218838; } #results { margin-top: 30px; padding: 25px; border: 1px solid var(–border-color); border-radius: 8px; background-color: var(–white); text-align: center; } #results h3 { margin-top: 0; font-size: 1.8em; color: var(–primary-color); } .result-item { margin-bottom: 15px; font-size: 1.1em; } .result-item .label { font-weight: bold; color: var(–primary-color); } .result-item .value { font-size: 1.4em; font-weight: bold; color: var(–success-color); } #primary-result { background-color: var(–success-color); color: var(–white); padding: 20px; border-radius: 8px; margin-bottom: 20px; font-size: 1.8em; font-weight: bold; display: flex; flex-direction: column; align-items: center; justify-content: center; } #primary-result .label { font-size: 0.8em; font-weight: normal; color: var(–white); opacity: 0.9; } #primary-result .value { font-size: 2em; color: var(–white); } .formula-explanation { font-size: 0.9em; color: #555; margin-top: 20px; padding-top: 15px; border-top: 1px dashed var(–border-color); } table { width: 100%; border-collapse: collapse; margin-top: 25px; margin-bottom: 30px; box-shadow: 0 2px 4px var(–shadow-color); } th, td { padding: 12px 15px; text-align: left; border: 1px solid var(–border-color); } th { background-color: var(–primary-color); color: var(–white); font-weight: bold; } td { background-color: var(–white); } tbody tr:nth-child(even) { background-color: #f2f2f2; } caption { caption-side: top; font-size: 1.2em; font-weight: bold; color: var(–primary-color); margin-bottom: 10px; text-align: left; } canvas { display: block; margin: 30px auto; background-color: var(–white); border-radius: 8px; box-shadow: 0 2px 4px var(–shadow-color); } .article-content { margin-top: 30px; background-color: var(–white); padding: 30px; border-radius: 8px; box-shadow: 0 4px 8px var(–shadow-color); } .article-content h2 { text-align: left; color: var(–primary-color); font-size: 2em; margin-bottom: 1em; } .article-content h3 { text-align: left; color: var(–primary-color); font-size: 1.5em; margin-top: 1.5em; margin-bottom: 0.7em; } .article-content p { margin-bottom: 1.2em; } .article-content ul, .article-content ol { margin-left: 20px; margin-bottom: 1.2em; } .article-content li { margin-bottom: 0.5em; } .article-content .faq-item { margin-bottom: 15px; } .article-content .faq-item .question { font-weight: bold; color: var(–primary-color); margin-bottom: 5px; display: block; } .article-content .faq-item .answer { font-size: 0.95em; color: #444; } .internal-links { margin-top: 30px; padding: 25px; border: 1px solid var(–border-color); border-radius: 8px; background-color: var(–white); } .internal-links h3 { text-align: left; margin-top: 0; color: var(–primary-color); font-size: 1.8em; } .internal-links ul { list-style: none; padding: 0; } .internal-links li { margin-bottom: 10px; } .internal-links a { color: var(–primary-color); text-decoration: none; font-weight: bold; } .internal-links a:hover { text-decoration: underline; } .internal-links p { font-size: 0.9em; color: #555; margin-top: 5px; } /* Specific styles for calculator inputs */ #weightUnit, #activityLevel, #goal { width: 100%; } @media (max-width: 768px) { .container { margin: 10px; padding: 15px; } h1 { font-size: 2em; } h2 { font-size: 1.7em; } .calc-header h2 { font-size: 1.7em; } #primary-result .value { font-size: 1.7em; } button { width: 100%; margin-bottom: 10px; } .loan-calc-container, #results, .article-content, .internal-links { padding: 15px; } canvas { max-width: 100%; } }

Calculate Calories to Eat to Lose Weight

Enter your details below to estimate your daily calorie intake for weight loss. This calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR) and then adjusts for your activity level and weight loss goal.

Your age in completed years.
Your current weight in kilograms.
Your current height in centimeters.
Male Female Select your gender.
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 lifestyle.
Lose 0.5 kg per week (approx. 500 calorie deficit) Lose 1 kg per week (approx. 1000 calorie deficit) Lose 0.25 kg per week (approx. 250 calorie deficit) Maintain Weight (0 calorie deficit) Select your desired weekly weight loss rate.

Your Weight Loss Calorie Estimate

Target Daily Calories for Weight Loss
Basal Metabolic Rate (BMR): kcal/day
Total Daily Energy Expenditure (TDEE): kcal/day
Calorie Deficit Needed: kcal/day
How it's calculated:

1. BMR is calculated using the Mifflin-St Jeor equation. For men: (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) + 5. For women: (10 * weight in kg) + (6.25 * height in cm) – (5 * age in years) – 161.
2. TDEE is BMR multiplied by your activity level factor.
3. Target Calories = TDEE – (Weekly Goal * 1100) / 7 (since 1 kg of fat is roughly 7700 calories, 0.5kg/week needs ~550, 1kg/week needs ~1100, adjusted for simplicity). A 500 kcal daily deficit generally leads to about 0.5 kg loss per week.

Calorie & Macronutrient Breakdown (Estimated)
Nutrient Percentage of Calories Grams per Day (Approx.)
Protein
Fat
Carbohydrates

*Macronutrient percentages are general recommendations for weight loss. Adjust based on personal needs and preferences. Protein: 4 kcal/g, Fat: 9 kcal/g, Carbs: 4 kcal/g.

Weight Loss Progress Chart

This chart estimates your weight loss trajectory over 12 weeks based on your target daily calorie deficit.

Understanding How to Calculate Calories to Eat to Lose Weight

Losing weight effectively boils down to a fundamental principle: energy balance. When you consistently consume fewer calories than your body burns, you create a calorie deficit, prompting your body to use stored fat for energy. Our calculator helps you determine a personalized daily calorie target to achieve this deficit safely and sustainably. Understanding this process is key to managing your weight and improving your overall health.

What is Calculate Calories to Eat to Lose Weight?

The "Calculate Calories to Eat to Lose Weight" process involves estimating your body's total daily energy expenditure (TDEE) and then subtracting a specific amount to create a calorie deficit. Your TDEE is the total number of calories you burn in a day, including those burned at rest (Basal Metabolic Rate or BMR), during physical activity, and through the thermic effect of food. By accurately calculating your TDEE and setting an appropriate deficit, you can create a roadmap for losing weight at a healthy pace.

Who should use it? Anyone looking to lose weight in a structured and informed manner should use this calculation. It's particularly useful for individuals who want to understand the numerical basis of their weight loss efforts, set realistic goals, and track progress. This calculator provides a personalized starting point, but it's essential to remember that individual responses to calorie restriction can vary.

Common misconceptions about calorie intake for weight loss include:

  • "You need to drastically cut calories." Extreme restriction can be counterproductive, leading to muscle loss, nutrient deficiencies, and a slowed metabolism. A moderate deficit is generally more sustainable.
  • "All calories are equal." While the energy content is the same, the source of calories matters for satiety, nutrient intake, and overall health. Nutrient-dense foods promote better health than processed, calorie-dense options.
  • "You can eat anything if you exercise." Exercise is crucial, but diet plays a larger role in weight loss. You cannot out-exercise a consistently high-calorie intake.
  • "Once you lose weight, you can go back to old habits." Sustainable weight management requires adopting and maintaining healthier eating habits long-term.

Calories to Eat to Lose Weight Formula and Mathematical Explanation

To calculate your target calorie intake for weight loss, we first need to determine your Basal Metabolic Rate (BMR) and then your Total Daily Energy Expenditure (TDEE). The most widely accepted formula for BMR is the Mifflin-St Jeor equation.

Mifflin-St Jeor Equation for BMR:

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

Total Daily Energy Expenditure (TDEE):

TDEE is calculated by multiplying your BMR by an activity factor that reflects your average daily physical activity level:

TDEE = BMR × Activity Factor

The activity factors are:

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

Calorie Deficit for Weight Loss:

To lose weight, you need to consume fewer calories than your TDEE. A common guideline is to create a deficit of 500 to 1000 calories per day to lose approximately 0.5 to 1 kg (1 to 2 pounds) per week. This is because roughly 7700 calories equal 1 kg of body fat.

Target Daily Calories = TDEE – Calorie Deficit

The calculator uses a weekly goal to derive the daily deficit:

  • 0.25 kg/week goal: ~250 kcal deficit/day (0.25 * 7700 / 7)
  • 0.5 kg/week goal: ~500 kcal deficit/day (0.5 * 7700 / 7)
  • 1 kg/week goal: ~1000 kcal deficit/day (1.0 * 7700 / 7)

Variables Table:

Variables Used in Calorie Calculation
Variable Meaning Unit Typical Range
Age Years since birth Years 18 – 90+
Weight Body mass Kilograms (kg) 30 – 200+
Height Body stature Centimeters (cm) 140 – 200+
Gender Biological sex Male/Female N/A
Activity Factor Multiplier based on daily physical activity Unitless 1.2 – 1.9
Weight Loss Goal Desired rate of weight loss kg/week 0 – 1.0
BMR Calories burned at rest kcal/day 1000 – 2500+
TDEE Total calories burned daily kcal/day 1500 – 4000+
Calorie Deficit Difference between TDEE and target intake kcal/day 250 – 1000
Target Daily Calories Recommended intake for weight loss kcal/day 1200 – 3000+

Practical Examples (Real-World Use Cases)

Example 1: A Moderately Active Woman Aiming for Steady Weight Loss

Scenario: Sarah is a 32-year-old woman, 165 cm tall, weighing 75 kg. She works an office job but goes to the gym for moderate workouts 3-4 times a week. She wants to lose about 0.5 kg per week.

Inputs:

  • Age: 32 years
  • Weight: 75 kg
  • Height: 165 cm
  • Gender: Female
  • Activity Level: Moderately Active (1.55)
  • Weight Loss Goal: 0.5 kg/week

Calculation Steps:

  • BMR (Female): (10 * 75) + (6.25 * 165) – (5 * 32) – 161 = 750 + 1031.25 – 160 – 161 = 1460.25 kcal/day
  • TDEE: 1460.25 * 1.55 = 2263.39 kcal/day
  • Calorie Deficit: 0.5 kg/week * 1100 kcal/kg / 7 days ≈ 785 kcal/day (calculator uses a rounded 500 kcal deficit for 0.5kg/wk for simplicity, let's use that)
  • Target Daily Calories: 2263.39 – 500 = 1763.39 kcal/day

Calculator Output Interpretation: Sarah should aim to consume approximately 1763 calories per day to lose about 0.5 kg per week. This deficit is manageable and conducive to sustainable weight loss without excessive hunger or fatigue. She might aim for around 1750-1800 calories, adjusting based on how she feels and her progress.

Example 2: An Active Man Losing Weight More Aggressively

Scenario: David is a 45-year-old man, 180 cm tall, weighing 90 kg. He has a physically demanding job and exercises vigorously 5-6 times a week. He wants to lose 1 kg per week.

Inputs:

  • Age: 45 years
  • Weight: 90 kg
  • Height: 180 cm
  • Gender: Male
  • Activity Level: Very Active (1.725)
  • Weight Loss Goal: 1 kg/week

Calculation Steps:

  • BMR (Male): (10 * 90) + (6.25 * 180) – (5 * 45) + 5 = 900 + 1125 – 225 + 5 = 1805 kcal/day
  • TDEE: 1805 * 1.725 = 3114.13 kcal/day
  • Calorie Deficit: 1 kg/week * 1100 kcal/kg / 7 days ≈ 1100 kcal/day (calculator uses a rounded 1000 kcal deficit for 1kg/wk for simplicity, let's use that)
  • Target Daily Calories: 3114.13 – 1000 = 2114.13 kcal/day

Calculator Output Interpretation: David needs to consume approximately 2114 calories per day to achieve a 1 kg weekly weight loss. This is an aggressive goal and requires a significant deficit. David should monitor his energy levels closely and ensure he is getting adequate nutrients. He might consider starting with a slightly smaller deficit if he experiences excessive fatigue or performance decline.

How to Use This Calculate Calories to Eat to Lose Weight Calculator

Using our calculator is straightforward. Follow these simple steps to get your personalized calorie target:

  1. Enter Your Age: Input your current age in years.
  2. Input Your Weight: Provide your current weight in kilograms.
  3. Enter Your Height: Input your current height in centimeters.
  4. Select Your Gender: Choose 'Male' or 'Female'.
  5. Choose Your Activity Level: Select the option that best describes your daily physical activity. Be honest to get the most accurate estimate.
  6. Set Your Weight Loss Goal: Choose your desired weekly weight loss rate (e.g., 0.5 kg or 1 kg per week). A slower rate is often more sustainable.
  7. View Your Results: Once you've entered all the information, the calculator will instantly display:
    • Target Daily Calories: Your recommended daily calorie intake for weight loss.
    • Basal Metabolic Rate (BMR): Calories burned at rest.
    • Total Daily Energy Expenditure (TDEE): Total calories burned daily.
    • Calorie Deficit Needed: The daily calorie reduction from your TDEE.
    • Estimated Macronutrient Breakdown: Suggested percentages and grams of protein, fat, and carbohydrates.
    • Weight Loss Progress Chart: An estimated visual of your weight loss journey.

How to read results: The primary result, "Target Daily Calories for Weight Loss," is your main guide. The BMR and TDEE show your baseline energy needs. The Calorie Deficit highlights how many calories you need to cut. The macronutrient table offers a balanced approach to your diet.

Decision-making guidance: Use your Target Daily Calories as a starting point. If you find it too difficult to adhere to, or if you're experiencing excessive fatigue, consider increasing your intake slightly (reducing the deficit) and aiming for a slower weight loss rate. If weight loss stalls after a few weeks, you may need to slightly decrease your intake further or increase your activity. Always consult with a healthcare professional or registered dietitian for personalized advice.

Key Factors That Affect Calculate Calories to Eat to Lose Weight Results

While our calculator provides a robust estimate, several factors can influence your actual calorie needs and weight loss progress. Understanding these can help you fine-tune your approach:

  1. Metabolic Adaptations: As you lose weight, your BMR and TDEE tend to decrease. Your body becomes more efficient, meaning you may need to adjust your calorie intake downwards over time to continue losing weight.
  2. Body Composition: Muscle tissue burns more calories at rest than fat tissue. Individuals with higher muscle mass will have a higher BMR than those of the same weight but with lower muscle mass.
  3. Hormonal Factors: Hormones like thyroid hormones, cortisol, and leptin play significant roles in metabolism and appetite regulation. Conditions like hypothyroidism can lower BMR.
  4. Genetics: Individual genetic makeup influences metabolism, fat storage, and response to dietary changes. Some people naturally have a faster metabolism.
  5. Dietary Thermogenesis: Different macronutrients require different amounts of energy to digest and absorb. Protein, for instance, has a higher thermic effect than carbohydrates or fats.
  6. Sleep Quality and Stress: Poor sleep and chronic stress can disrupt hormones (like cortisol), increase appetite, and lead to cravings for high-calorie foods, potentially hindering weight loss efforts.
  7. Medications: Certain medications can affect metabolism, appetite, or weight gain as a side effect.
  8. Non-Exercise Activity Thermogenesis (NEAT): This includes all the calories burned from activities outside of planned exercise, like fidgeting, walking around the office, or even standing. NEAT can vary significantly between individuals.

Frequently Asked Questions (FAQ)

What is the safest rate of weight loss? A safe and sustainable rate of weight loss is generally considered to be 0.5 kg to 1 kg (1 to 2 pounds) per week. Faster rates can increase the risk of muscle loss, nutrient deficiencies, and gallstones.
Can I eat less than 1200 calories per day? For most adult women, consuming fewer than 1200 calories per day is generally not recommended without medical supervision, as it can be difficult to meet nutritional needs. For men, the threshold is often considered around 1500 calories. Extreme restriction can slow metabolism.
Does my metabolism slow down when I diet? Yes, your metabolism can slow down somewhat when you consume fewer calories. This is a natural adaptive response by the body to conserve energy. However, a moderate calorie deficit is less likely to cause significant metabolic slowdown compared to extreme dieting.
How accurate is this calculator? This calculator provides an estimate based on established formulas (Mifflin-St Jeor). Individual metabolic rates and responses to diet can vary due to genetics, body composition, hormones, and other factors. It's a great starting point, but adjustments based on your personal experience are often necessary.
What if I'm pregnant or breastfeeding? This calculator is not suitable for pregnant or breastfeeding individuals. Calorie needs are significantly different during these periods and require specific medical guidance.
How do I adjust my calorie intake if I don't lose weight? If you're not losing weight after consistently following your calorie target for a couple of weeks, you might need to slightly decrease your intake further (e.g., by 100-200 calories) or increase your physical activity to enhance the calorie deficit. Ensure you're accurately tracking your intake.
Should I focus on macronutrients or just calories? While calories are the primary driver of weight loss, macronutrient balance is crucial for satiety, muscle preservation, and overall health. A balanced intake of protein, healthy fats, and complex carbohydrates is generally recommended alongside a calorie deficit.
What happens if I exceed my target calories occasionally? Occasional splurges are normal and don't typically derail long-term progress if they are infrequent. Focus on consistency over perfection. If you go over your target one day, simply get back on track with your next meal or the next day.

Related Tools and Internal Resources

© 2023 Your Financial Hub. All rights reserved. This calculator is for informational purposes only and does not constitute medical advice.

var ageInput = document.getElementById('age'); var weightInput = document.getElementById('weight'); var heightInput = document.getElementById('height'); var genderSelect = document.getElementById('gender'); var activityLevelSelect = document.getElementById('activityLevel'); var goalSelect = document.getElementById('goal'); var ageError = document.getElementById('ageError'); var weightError = document.getElementById('weightError'); var heightError = document.getElementById('heightError'); var bmrValueDisplay = document.getElementById('bmrValue'); var tdeeValueDisplay = document.getElementById('tdeeValue'); var calorieDeficitDisplay = document.getElementById('calorieDeficit'); var targetCaloriesDisplay = document.getElementById('targetCalories'); var proteinPercentDisplay = document.getElementById('proteinPercent'); var proteinGramsDisplay = document.getElementById('proteinGrams'); var fatPercentDisplay = document.getElementById('fatPercent'); var fatGramsDisplay = document.getElementById('fatGrams'); var carbPercentDisplay = document.getElementById('carbPercent'); var carbGramsDisplay = document.getElementById('carbGrams'); var chartCanvas = document.getElementById('progressChart'); var chartInstance = null; // To hold the Chart.js instance function validateInput(inputElement, errorElement, minValue, maxValue, errorMessage) { var value = parseFloat(inputElement.value); var isValid = true; if (isNaN(value) || value <= 0) { errorElement.textContent = "Please enter a valid positive number."; errorElement.classList.add('visible'); isValid = false; } else if (minValue !== null && value maxValue) { errorElement.textContent = `Value must be no more than ${maxValue}.`; errorElement.classList.add('visible'); isValid = false; } else { errorElement.textContent = ""; errorElement.classList.remove('visible'); } return isValid; } function calculateCalories() { // Clear previous errors ageError.textContent = ""; ageError.classList.remove('visible'); weightError.textContent = ""; weightError.classList.remove('visible'); heightError.textContent = ""; heightError.classList.remove('visible'); // Get input values var age = parseFloat(ageInput.value); var weight = parseFloat(weightInput.value); var height = parseFloat(heightInput.value); var gender = genderSelect.value; var activityFactor = parseFloat(activityLevelSelect.value); var goalWeightLossPerWeek = parseFloat(goalSelect.value); // in kg/week // Validate inputs var isAgeValid = validateInput(ageInput, ageError, 1, 120); var isWeightValid = validateInput(weightInput, weightError, 1, 1000); var isHeightValid = validateInput(heightInput, heightError, 1, 300); if (!isAgeValid || !isWeightValid || !isHeightValid) { resetResultsDisplay(); return; } // Calculate BMR using Mifflin-St Jeor var bmr = 0; 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 * activityFactor; // Calculate calorie deficit based on goal (approximate) // 1 kg fat ~ 7700 kcal. // 0.25kg/wk -> 0.25 * 7700 / 7 = ~275 kcal deficit/day // 0.5kg/wk -> 0.5 * 7700 / 7 = ~550 kcal deficit/day // 1.0kg/wk -> 1.0 * 7700 / 7 = ~1100 kcal deficit/day // Using slightly rounded values for simplicity in explanation. var deficitPerDay = 0; if (goalWeightLossPerWeek === 0.25) deficitPerDay = 250; else if (goalWeightLossPerWeek === 0.5) deficitPerDay = 500; else if (goalWeightLossPerWeek === 1.0) deficitPerDay = 1000; // If goal is 0, deficitPerDay remains 0 (maintenance) var targetCalories = tdee – deficitPerDay; // Ensure target calories don't go below a safe minimum (e.g., 1200 for women, 1500 for men) var minCalories = (gender === 'female') ? 1200 : 1500; if (targetCalories < minCalories) { targetCalories = minCalories; // Adjust deficit if we hit the minimum deficitPerDay = tdee – targetCalories; } // Update results display bmrValueDisplay.textContent = bmr.toFixed(0); tdeeValueDisplay.textContent = tdee.toFixed(0); calorieDeficitDisplay.textContent = deficitPerDay.toFixed(0); targetCaloriesDisplay.textContent = targetCalories.toFixed(0); // Update Macronutrient Table (General recommendations for weight loss) var proteinPerc = 30; // 30% Protein var fatPerc = 25; // 25% Fat var carbPerc = 45; // 45% Carbs var proteinKcal = (targetCalories * proteinPerc) / 100; var fatKcal = (targetCalories * fatPerc) / 100; var carbKcal = (targetCalories * carbPerc) / 100; var proteinGrams = proteinKcal / 4; var fatGrams = fatKcal / 9; var carbGrams = carbKcal / 4; proteinPercentDisplay.textContent = proteinPerc + "%"; proteinGramsDisplay.textContent = proteinGrams.toFixed(1); fatPercentDisplay.textContent = fatPerc + "%"; fatGramsDisplay.textContent = fatGrams.toFixed(1); carbPercentDisplay.textContent = carbPerc + "%"; carbGramsDisplay.textContent = carbGrams.toFixed(1); updateChart(targetCalories, deficitPerDay, goalWeightLossPerWeek); } function resetResultsDisplay() { bmrValueDisplay.textContent = "–"; tdeeValueDisplay.textContent = "–"; calorieDeficitDisplay.textContent = "–"; targetCaloriesDisplay.textContent = "–"; proteinPercentDisplay.textContent = "–"; proteinGramsDisplay.textContent = "–"; fatPercentDisplay.textContent = "–"; fatGramsDisplay.textContent = "–"; carbPercentDisplay.textContent = "–"; carbGramsDisplay.textContent = "–"; if (chartInstance) { chartInstance.destroy(); chartInstance = null; } // Clear canvas if chart is destroyed var ctx = chartCanvas.getContext('2d'); ctx.clearRect(0, 0, chartCanvas.width, chartCanvas.height); } function resetCalculator() { ageInput.value = '30'; weightInput.value = '70'; heightInput.value = '175'; genderSelect.value = 'male'; activityLevelSelect.value = '1.2'; // Sedentary goalSelect.value = '0.5'; // Lose 0.5 kg/week // Clear errors ageError.textContent = ""; ageError.classList.remove('visible'); weightError.textContent = ""; weightError.classList.remove('visible'); heightError.textContent = ""; heightError.classList.remove('visible'); calculateCalories(); } function copyResults() { var primaryResult = targetCaloriesDisplay.textContent; var bmrResult = bmrValueDisplay.textContent; var tdeeResult = tdeeValueDisplay.textContent; var deficitResult = calorieDeficitDisplay.textContent; var proteinPerc = proteinPercentDisplay.textContent; var proteinGrams = proteinGramsDisplay.textContent; var fatPerc = fatPercentDisplay.textContent; var fatGrams = fatGramsDisplay.textContent; var carbPerc = carbPercentDisplay.textContent; var carbGrams = carbGramsDisplay.textContent; var copyText = `— Weight Loss Calorie Estimate — Target Daily Calories: ${primaryResult} kcal/day Basal Metabolic Rate (BMR): ${bmrResult} kcal/day Total Daily Energy Expenditure (TDEE): ${tdeeResult} kcal/day Calorie Deficit Needed: ${deficitResult} kcal/day — Estimated Macronutrient Breakdown — Protein: ${proteinPerc} (${proteinGrams}g) Fat: ${fatPerc} (${fatGrams}g) Carbohydrates: ${carbPerc} (${carbGrams}g) — Key Assumptions — Activity Level Factor: ${activityLevelSelect.options[activityLevelSelect.selectedIndex].text} Weight Loss Goal: ${goalSelect.options[goalSelect.selectedIndex].text} `; // Use a temporary textarea to copy text var textArea = document.createElement("textarea"); textArea.value = copyText; textArea.style.position = "fixed"; textArea.style.left = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied!' : 'Copying failed'; alert(msg); // Simple feedback } catch (err) { alert('Oops, unable to copy'); } document.body.removeChild(textArea); } function updateChart(targetCalories, deficitPerDay, goalWeightLossPerWeek) { if (chartInstance) { chartInstance.destroy(); } var ctx = chartCanvas.getContext('2d'); var weeks = []; var projectedWeights = []; var initialWeight = parseFloat(weightInput.value); // Use current weight as starting point // Calculate projected weights for 12 weeks for (var i = 0; i 0 ? projectedWeight : 0); // Ensure weight doesn't go below 0 } chartInstance = new Chart(ctx, { type: 'line', data: { labels: weeks.map(week => week === 0 ? 'Start' : `${week} Wk`), datasets: [{ label: 'Projected Weight (kg)', data: projectedWeights, borderColor: 'rgba(0, 74, 153, 1)', // Primary color backgroundColor: 'rgba(0, 74, 153, 0.2)', fill: true, tension: 0.1 }, { label: 'Target Calorie Intake (kcal)', data: Array(weeks.length).fill(targetCalories), borderColor: 'rgba(40, 167, 69, 1)', // Success color borderDash: [5, 5], fill: false, pointRadius: 0 // Hide points for this line }] }, options: { responsive: true, maintainAspectRatio: true, scales: { y: { beginAtZero: false, title: { display: true, text: 'Weight (kg) / Calories (kcal)' } }, x: { title: { display: true, text: 'Time' } } }, plugins: { tooltip: { mode: 'index', intersect: false }, legend: { position: 'top' } } } }); } // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { // Set default values and calculate resetCalculator(); // Add event listener for Enter key to trigger calculation document.querySelectorAll('.loan-calc-container input, .loan-calc-container select').forEach(function(element) { element.addEventListener('keypress', function(e) { if (e.key === 'Enter') { calculateCalories(); } }); }); });

Leave a Comment