Estimate your daily calorie intake for weight maintenance, loss, or gain based on your Basal Metabolic Rate (BMR) and activity level.
Male
Female
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/week)
Extra active (very hard exercise/sports & physical job)
Your Estimated Daily Calorie Needs
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Understanding Your Calorie Needs
Calculating your daily calorie needs is fundamental to managing your weight and overall health. It involves understanding your Basal Metabolic Rate (BMR) – the number of calories your body burns at rest – and then factoring in your physical activity level. This calculator uses the widely accepted Mifflin-St Jeor equation to estimate BMR, which is generally considered more accurate than older formulas like Harris-Benedict.
The Math Behind the Calculator
1. Basal Metabolic Rate (BMR):
This is the energy expenditure of your body in a completely rested state. The Mifflin-St Jeor equation is used:
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
2. Total Daily Energy Expenditure (TDEE):
This is your BMR multiplied by an activity factor that represents your lifestyle. The activity factors used in this calculator are standard estimates:
Sedentary (1.2): Little to no exercise, desk job.
Lightly Active (1.375): Light exercise or sports 1-3 days per week.
Moderately Active (1.55): Moderate exercise or sports 3-5 days per week.
Very Active (1.725): Hard exercise or sports 6-7 days per week.
Extra Active (1.9): Very hard exercise or sports and/or a physical job.
The formula for TDEE is:
TDEE = BMR × Activity Factor
How to Use This Calculator
Select your Gender.
Enter your current Age in years.
Input your current Weight in kilograms (kg).
Input your current Height in centimeters (cm).
Choose your typical Activity Level from the dropdown menu.
Click the "Calculate Daily Calories" button.
The result will show your estimated TDEE, which is the number of calories you need to consume daily to maintain your current weight.
Weight Management Goals
To Lose Weight: Consume 500-1000 calories less than your TDEE per day.
To Gain Weight: Consume 500-1000 calories more than your TDEE per day.
Disclaimer: This calculator provides an estimate. Individual metabolic rates can vary. For personalized advice, consult a healthcare professional or a registered dietitian.
function calculateCalories() {
var gender = document.getElementById("gender").value;
var age = parseFloat(document.getElementById("age").value);
var weight = parseFloat(document.getElementById("weight").value);
var height = parseFloat(document.getElementById("height").value);
var activityLevel = parseFloat(document.getElementById("activityLevel").value);
var bmr = 0;
var tdee = 0;
var resultDescription = "";
// Validate inputs
if (isNaN(age) || isNaN(weight) || isNaN(height) || isNaN(activityLevel) || age <= 0 || weight <= 0 || height 0) {
resultDescription = "This is your estimated daily calorie intake to maintain your current weight. To lose weight, aim for 500-1000 calories less. To gain weight, aim for 500-1000 calories more.";
} else {
resultDescription = "Could not calculate TDEE with the provided inputs.";
}
document.getElementById("result-description").innerText = resultDescription;
}