Metabolic Rate Calculator (Activity Level)
This calculator helps you estimate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) based on your personal details and activity level. Understanding your metabolic rate is crucial for managing your weight, optimizing your fitness, and ensuring you consume adequate energy to support your body's functions.
What is Metabolic Rate?
Metabolic rate refers to the rate at which your body burns calories to produce energy. It's influenced by several factors, including your age, sex, weight, height, and most importantly, your activity level. There are two main components to consider:
- Basal Metabolic Rate (BMR): This is the number of calories your body burns at rest to maintain basic life-sustaining functions like breathing, circulation, and cell production.
- Total Daily Energy Expenditure (TDEE): This is the total number of calories you burn in a day, including your BMR plus the calories burned through physical activity and the thermic effect of food.
How to Use This Calculator:
1. Enter your current weight in kilograms (kg).
2. Enter your height in centimeters (cm).
3. Enter your age in years.
4. Select your gender.
5. Choose your activity level from the dropdown menu. This is a crucial factor as more active individuals require more calories.
6. Click "Calculate" to see your estimated BMR and TDEE.
Understanding the Results:
Your BMR provides a baseline of your caloric needs. Your TDEE is a more accurate reflection of the calories you need to consume daily to maintain your current weight, considering all your daily activities. Adjusting your caloric intake based on your TDEE can help you achieve weight loss, weight gain, or weight maintenance goals.
function calculateMetabolicRate() {
var weight = parseFloat(document.getElementById("weight").value);
var height = parseFloat(document.getElementById("height").value);
var age = parseInt(document.getElementById("age").value);
var gender = document.getElementById("gender").value;
var activityLevelMultiplier = parseFloat(document.getElementById("activityLevel").value);
var bmr = 0;
if (isNaN(weight) || isNaN(height) || isNaN(age) || weight <= 0 || height <= 0 || age <= 0) {
document.getElementById("result").innerHTML = "Please enter valid numbers for weight, height, and age.";
return;
}
// Mifflin-St Jeor Equation (commonly used and generally accurate)
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 = bmr * activityLevelMultiplier;
document.getElementById("result").innerHTML =
"Your estimated Basal Metabolic Rate (BMR) is:
" + bmr.toFixed(2) + " kcal/day" +
"Your estimated Total Daily Energy Expenditure (TDEE) is:
" + tdee.toFixed(2) + " kcal/day";
}
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