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)
Your Estimated Daily Calorie Needs:
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kcal
Understanding Your Daily Calorie Needs
Calculating your daily calorie needs is a fundamental step towards managing your weight, improving your fitness, and maintaining overall health. The number of calories your body requires each day depends on several factors, including your age, gender, weight, height, and activity level. This calculator uses the Mifflin-St Jeor equation, which is widely considered one of the most accurate formulas for estimating Basal Metabolic Rate (BMR) and then adjusts it for your activity level to determine your Total Daily Energy Expenditure (TDEE).
Basal Metabolic Rate (BMR)
Your BMR is the number of calories your body burns at rest to maintain basic life functions such as breathing, circulation, and cell production. The Mifflin-St Jeor equation is calculated as follows:
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)
Once your BMR is calculated, it's multiplied by an activity factor to estimate your TDEE. This factor accounts for the calories you burn through daily activities, exercise, and the thermic effect of food. The activity factors used in this calculator are:
Sedentary: BMR × 1.2
Lightly active: BMR × 1.375
Moderately active: BMR × 1.55
Very active: BMR × 1.725
Extra active: BMR × 1.9
The result of this calculation is your estimated daily calorie intake needed to maintain your current weight.
How to Use This Calculator
To get your personalized calorie estimate:
Enter your Age in years.
Select your Gender.
Input your current Weight in kilograms.
Input your current Height in centimeters.
Choose your typical Activity Level from the dropdown menu.
Click the "Calculate Daily Calories" button.
The calculator will then display your estimated daily calorie needs in kilocalories (kcal). This number is a guideline; individual metabolic rates can vary. For precise dietary planning, especially if you have specific health goals or conditions, consulting a healthcare professional or a registered dietitian is recommended.
function calculateCalories() {
var age = document.getElementById("age").value;
var gender = document.getElementById("gender").value;
var weight = document.getElementById("weight").value;
var height = document.getElementById("height").value;
var activityLevel = document.getElementById("activityLevel").value;
var bmr = 0;
// Validate inputs
if (age === "" || weight === "" || height === "" || isNaN(age) || isNaN(weight) || isNaN(height) || age <= 0 || weight <= 0 || height <= 0) {
document.getElementById("result-value").innerText = "Invalid Input";
document.getElementById("result-unit").innerText = "";
return;
}
age = parseFloat(age);
weight = parseFloat(weight);
height = parseFloat(height);
activityLevel = parseFloat(activityLevel);
// 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
document.getElementById("result-value").innerText = tdee.toFixed(0);
document.getElementById("result-unit").innerText = "kcal";
}