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 or 2x training)
Estimated Daily Xalorie Needs:
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Based on your inputs.
Understanding the Xalorie Calculator (Basal Metabolic Rate & Total Daily Energy Expenditure)
The "Xalorie Calculator" is a tool designed to estimate your daily energy needs, often referred to as Total Daily Energy Expenditure (TDEE). This is crucial for individuals looking to manage their weight, whether for gaining, losing, or maintaining it. It combines your Basal Metabolic Rate (BMR) with an adjustment for your physical activity level.
What is Basal Metabolic Rate (BMR)?
BMR is the minimum number of calories your body needs to perform basic life-sustaining functions while at rest. This includes breathing, circulation, cell production, nutrient processing, and protein synthesis. It's the energy your body expends just to keep you alive and functioning if you were to do nothing all day.
How BMR is Calculated (Mifflin-St Jeor Equation)
This calculator uses the widely accepted Mifflin-St Jeor equation, which is considered one of the most accurate BMR calculators available:
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
What is Total Daily Energy Expenditure (TDEE)?
TDEE is a more comprehensive measure of your daily calorie needs. It accounts for your BMR plus the calories burned through all forms of physical activity, including exercise and non-exercise activity thermogenesis (NEAT), which is the energy expended for everything we do that is not sleeping, eating, or planned exercise (e.g., walking to work, typing, fidgeting).
How TDEE is Calculated
TDEE is calculated by multiplying your BMR by an activity factor:
TDEE = BMR × Activity Factor
The activity factors used in this calculator are standard estimations:
Very active: BMR × 1.725 (hard exercise/sports 6-7 days/week)
Extra active: BMR × 1.9 (very hard exercise/sports & physical job or training twice a day)
Use Cases for the Xalorie Calculator
Weight Management: To lose weight, you generally need to consume fewer calories than your TDEE. To gain weight, you need to consume more calories than your TDEE.
Fitness Planning: Understanding your energy expenditure helps in structuring training and nutrition plans for athletes and fitness enthusiasts.
General Health: Maintaining a healthy weight is crucial for overall well-being and reducing the risk of chronic diseases.
Disclaimer: This calculator provides an estimate. Individual metabolic rates can vary. For personalized dietary and health advice, consult a healthcare professional or a registered dietitian.
function calculateXalories() {
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 activityLevel = parseFloat(document.getElementById("activityLevel").value);
var bmr = 0;
var resultElement = document.getElementById("result-value");
var errorMessageElement = document.getElementById("errorMessage");
// Clear previous error messages
if (errorMessageElement) {
errorMessageElement.remove();
}
// Input validation
if (isNaN(weight) || weight <= 0 ||
isNaN(height) || height <= 0 ||
isNaN(age) || age <= 0 ||
isNaN(activityLevel)) {
displayError("Please enter valid positive numbers for weight, height, and age.");
return;
}
// Calculate BMR using 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;
}
// Calculate TDEE
var tdee = bmr * activityLevel;
// Display the result
resultElement.textContent = Math.round(tdee) + " Xalories";
}
function displayError(message) {
var resultDiv = document.getElementById("result");
var errorMessageElement = document.createElement("p");
errorMessageElement.id = "errorMessage";
errorMessageElement.style.color = "red";
errorMessageElement.style.marginTop = "15px";
errorMessageElement.textContent = message;
resultDiv.parentNode.insertBefore(errorMessageElement, resultDiv);
document.getElementById("result-value").textContent = "–";
}