Calculating Food

Daily Calorie Needs Calculator

kg lbs

cm inches

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/physical job/training twice a day)

function calculateCalorieNeeds() { var age = parseFloat(document.getElementById('ageInput').value); var genderMale = document.getElementById('genderMale').checked; var weight = parseFloat(document.getElementById('weightInput').value); var weightUnit = document.getElementById('weightUnit').value; var height = parseFloat(document.getElementById('heightInput').value); var heightUnit = document.getElementById('heightUnit').value; var activityLevel = document.getElementById('activityLevel').value; var resultDiv = document.getElementById('result'); if (isNaN(age) || age <= 0 || isNaN(weight) || weight <= 0 || isNaN(height) || height <= 0) { resultDiv.innerHTML = 'Please enter valid positive numbers for age, weight, and height.'; return; } // Convert weight to kg if necessary var weight_kg = weight; if (weightUnit === 'lbs') { weight_kg = weight * 0.453592; } // Convert height to cm if necessary var height_cm = height; if (heightUnit === 'inches') { height_cm = height * 2.54; } var bmr; // Basal Metabolic Rate // Mifflin-St Jeor Equation for BMR if (genderMale) { bmr = (10 * weight_kg) + (6.25 * height_cm) – (5 * age) + 5; } else { // Female bmr = (10 * weight_kg) + (6.25 * height_cm) – (5 * age) – 161; } var activityFactor; switch (activityLevel) { case 'sedentary': activityFactor = 1.2; break; case 'lightly_active': activityFactor = 1.375; break; case 'moderately_active': activityFactor = 1.55; break; case 'very_active': activityFactor = 1.725; break; case 'extra_active': activityFactor = 1.9; break; default: activityFactor = 1.2; // Default to sedentary } var tdee = bmr * activityFactor; // Total Daily Energy Expenditure resultDiv.innerHTML = 'Estimated Basal Metabolic Rate (BMR): ' + bmr.toFixed(0) + ' calories/day' + 'Estimated Total Daily Calorie Needs (TDEE): ' + tdee.toFixed(0) + ' calories/day' + 'These are estimates. Individual needs may vary.'; } // Run calculation on page load with default values document.addEventListener('DOMContentLoaded', function() { calculateCalorieNeeds(); });

Understanding Your Daily Calorie Needs

Calculating your daily calorie needs is a fundamental step towards managing your weight, whether you're looking to lose, maintain, or gain. This calculator uses widely accepted formulas to provide an estimate of how many calories your body burns each day, both at rest and with activity.

What is Basal Metabolic Rate (BMR)?

Your Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic, life-sustaining functions while at rest. These essential functions include breathing, circulation, cell production, nutrient processing, and maintaining body temperature. Even if you were to lie in bed all day, your body would still burn calories to keep you alive. Our calculator uses the Mifflin-St Jeor equation, which is considered one of the most accurate BMR formulas.

• 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

As you can see, factors like age, gender, weight, and height all play a significant role in determining your BMR.

What is Total Daily Energy Expenditure (TDEE)?

While BMR accounts for calories burned at rest, your Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a 24-hour period, including all activities. This includes your BMR plus the calories you burn through physical activity, digestion, and other daily movements. To calculate TDEE, your BMR is multiplied by an activity factor:

• Sedentary: BMR × 1.2 (little to no exercise)
• Lightly Active: BMR × 1.375 (light exercise/sports 1-3 days/week)
• Moderately Active: BMR × 1.55 (moderate exercise/sports 3-5 days/week)
• Very Active: BMR × 1.725 (hard exercise/sports 6-7 days/week)
• Extra Active: BMR × 1.9 (very hard exercise/physical job/training twice a day)

The more active you are, the higher your TDEE will be, as your body requires more energy to fuel your movements and workouts.

How to Use Your Calorie Needs Results

Once you have your estimated TDEE, you can use this number as a baseline for your dietary goals:

• For Weight Maintenance: Consume roughly the same number of calories as your TDEE.
• For Weight Loss: Consume fewer calories than your TDEE. A common recommendation is a deficit of 500 calories per day to lose about 1 pound (0.45 kg) per week.
• For Weight Gain: Consume more calories than your TDEE. A surplus of 250-500 calories per day is often recommended for healthy weight gain.

Remember that these calculations provide estimates. Individual metabolism, body composition, and other factors can cause actual calorie needs to vary. It's always a good idea to monitor your progress and adjust your intake as needed. Consulting with a healthcare professional or a registered dietitian can provide personalized guidance.

Example Calculation:

Let's consider a 30-year-old male, weighing 75 kg, standing 180 cm tall, and moderately active.

1. BMR Calculation:
   BMR = (10 × 75 kg) + (6.25 × 180 cm) – (5 × 30 years) + 5
   BMR = 750 + 1125 – 150 + 5
   BMR = 1730 calories/day
2. TDEE Calculation:
   For a moderately active individual, the activity factor is 1.55.
   TDEE = BMR × Activity Factor
   TDEE = 1730 × 1.55
   TDEE = 2681.5 calories/day

So, this individual would need approximately 2682 calories per day to maintain their current weight. To lose weight, they would aim for fewer calories, and to gain weight, they would aim for more.