Calaries Calculator

Daily Calorie Needs Calculator

Estimate your daily calorie requirements to maintain, lose, or gain weight using the Mifflin-St Jeor equation, considered one of the most accurate BMR formulas.

function calculateCalories() { var age = parseFloat(document.getElementById('age').value); var gender = document.querySelector('input[name="gender"]:checked').value; var weight = parseFloat(document.getElementById('weight').value); var height = parseFloat(document.getElementById('height').value); var activityLevel = document.getElementById('activityLevel').value; var goal = document.querySelector('input[name="goal"]:checked').value; if (isNaN(age) || isNaN(weight) || isNaN(height) || age <= 0 || weight <= 0 || height <= 0) { document.getElementById('calorieResult').innerHTML = 'Please enter valid positive numbers for age, weight, and height.'; return; } var bmr; // Basal Metabolic Rate // Mifflin-St Jeor Equation if (gender === 'male') { bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5; } else { // female bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161; } var tdee; // Total Daily Energy Expenditure // Activity Level Multipliers switch (activityLevel) { case 'sedentary': tdee = bmr * 1.2; break; case 'lightlyActive': tdee = bmr * 1.375; break; case 'moderatelyActive': tdee = bmr * 1.55; break; case 'veryActive': tdee = bmr * 1.725; break; case 'extraActive': tdee = bmr * 1.9; break; default: tdee = bmr * 1.2; // Default to sedentary if somehow no option is selected } var targetCalories = tdee; // Adjust for weight goal if (goal === 'lose') { targetCalories -= 500; // Approximately 0.5 kg (1 lb) weight loss per week } else if (goal === 'gain') { targetCalories += 500; // Approximately 0.5 kg (1 lb) weight gain per week } document.getElementById('calorieResult').innerHTML = '

Your Estimated Daily Calorie Needs:

' + 'Your Basal Metabolic Rate (BMR): ' + Math.round(bmr) + ' calories/day' + 'Your Total Daily Energy Expenditure (TDEE): ' + Math.round(tdee) + ' calories/day' + 'To ' + goal.charAt(0).toUpperCase() + goal.slice(1) + ' Weight: You need approximately ' + Math.round(targetCalories) + ' calories/day' + 'Note: These are estimates. Individual needs may vary. Consult a healthcare professional or registered dietitian for personalized advice.'; } .calories-calculator-container { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f9f9f9; padding: 25px; border-radius: 10px; box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1); max-width: 600px; margin: 30px auto; border: 1px solid #e0e0e0; } .calories-calculator-container h2 { text-align: center; color: #333; margin-bottom: 20px; font-size: 1.8em; } .calories-calculator-container p { color: #555; line-height: 1.6; margin-bottom: 15px; } .calculator-form .form-group { margin-bottom: 18px; display: flex; flex-wrap: wrap; align-items: center; } .calculator-form label { flex: 1; min-width: 120px; color: #444; font-weight: bold; margin-right: 15px; } .calculator-form input[type="number"], .calculator-form select { flex: 2; padding: 10px 12px; border: 1px solid #ccc; border-radius: 5px; font-size: 1em; max-width: calc(100% – 150px); /* Adjust based on label width */ box-sizing: border-box; } .calculator-form input[type="radio"] { margin-right: 5px; margin-left: 15px; } .calculator-form input[type="radio"] + label { font-weight: normal; color: #555; flex: none; min-width: unset; margin-right: 20px; } .calculator-form button { display: block; width: 100%; padding: 12px 20px; background-color: #007bff; color: white; border: none; border-radius: 5px; font-size: 1.1em; cursor: pointer; transition: background-color 0.3s ease; margin-top: 25px; } .calculator-form button:hover { background-color: #0056b3; } .calculator-result { margin-top: 30px; padding: 20px; background-color: #e9f7ef; border: 1px solid #d4edda; border-radius: 8px; color: #155724; text-align: center; } .calculator-result h3 { color: #0f5132; margin-top: 0; font-size: 1.5em; } .calculator-result p { margin-bottom: 8px; font-size: 1.1em; } .calculator-result p strong { color: #0f5132; } .calculator-result .disclaimer { font-size: 0.9em; color: #6c757d; margin-top: 15px; } @media (max-width: 480px) { .calculator-form label { flex: 100%; margin-bottom: 5px; } .calculator-form input[type="number"], .calculator-form select { flex: 100%; max-width: 100%; } .calculator-form input[type="radio"] + label { margin-left: 0; } }

Understanding Your Calorie Needs

Calories are units of energy that your body uses to perform all its functions, from breathing and thinking to exercising and digesting food. The number of calories you need daily depends on several factors, including your age, gender, weight, height, and activity level.

How the Calculator Works

This calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR) and then adjusts it based on your activity level to determine your Total Daily Energy Expenditure (TDEE). Finally, it modifies your TDEE based on your weight goal (maintain, lose, or gain).

• Basal Metabolic Rate (BMR): This is the number of calories your body burns at rest to maintain basic bodily functions like breathing, circulation, and cell production. It's the minimum energy required to keep you alive.
• Total Daily Energy Expenditure (TDEE): This is your BMR plus the calories you burn through physical activity and the thermic effect of food (energy used for digestion). It represents the total calories your body expends in a day.
• Activity Levels:
  • 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/physical job/training twice a day.
• Weight Goals:
  • Maintain Weight: Your target calories will be approximately your TDEE.
  • Lose Weight: The calculator subtracts about 500 calories from your TDEE, aiming for a healthy weight loss of approximately 0.5 kg (1 pound) per week.
  • Gain Weight: The calculator adds about 500 calories to your TDEE, aiming for a healthy weight gain of approximately 0.5 kg (1 pound) per week.

Why Calculate Your Calorie Needs?

Knowing your estimated daily calorie needs can be a powerful tool for managing your weight and improving your overall health. It provides a baseline for planning your diet and exercise. Whether you're looking to shed a few pounds, build muscle, or simply maintain your current physique, understanding your caloric requirements is the first step.

Important Considerations

While this calculator provides a good estimate, individual calorie needs can vary due to factors like genetics, body composition (muscle vs. fat), hormonal balance, and specific health conditions. Always consider these results as a starting point. For personalized dietary advice and health plans, it is highly recommended to consult with a healthcare professional or a registered dietitian.