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/physical job/training twice a day)
Maintain Weight
Mild Weight Loss (0.25 kg/week)
Weight Loss (0.5 kg/week)
Extreme Weight Loss (1 kg/week)
Mild Weight Gain (0.25 kg/week)
Weight Gain (0.5 kg/week)
Extreme Weight Gain (1 kg/week)
Enter your details and click "Calculate Daily Calories" to see your estimated daily calorie needs.
This calculator provides an estimate based on common formulas. Individual calorie needs can vary based on metabolism, body composition, and other factors. Always consult with a healthcare professional or registered dietitian for personalized advice.
function calculateCalories() {
var age = parseFloat(document.getElementById("age").value);
var weight = parseFloat(document.getElementById("weight").value);
var height = parseFloat(document.getElementById("height").value);
var genderMale = document.getElementById("genderMale").checked;
var activityMultiplier = parseFloat(document.getElementById("activityLevel").value);
var goal = document.getElementById("goal").value;
var resultDiv = document.getElementById("calorieResult");
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;
}
var bmr;
// Mifflin-St Jeor Equation
if (genderMale) {
bmr = (10 * weight) + (6.25 * height) – (5 * age) + 5;
} else { // Female
bmr = (10 * weight) + (6.25 * height) – (5 * age) – 161;
}
var tdee = bmr * activityMultiplier;
var dailyCalories = tdee;
switch (goal) {
case "maintain":
// No adjustment needed
break;
case "mildLoss": // ~0.25 kg/week = 250 kcal/day deficit
dailyCalories -= 250;
break;
case "loss": // ~0.5 kg/week = 500 kcal/day deficit
dailyCalories -= 500;
break;
case "extremeLoss": // ~1 kg/week = 1000 kcal/day deficit
dailyCalories -= 1000;
break;
case "mildGain": // ~0.25 kg/week = 250 kcal/day surplus
dailyCalories += 250;
break;
case "gain": // ~0.5 kg/week = 500 kcal/day surplus
dailyCalories += 500;
break;
case "extremeGain": // ~1 kg/week = 1000 kcal/day surplus
dailyCalories += 1000;
break;
}
// Ensure calories don't go too low for extreme loss, though this is a basic calculator
if (dailyCalories < 1200 && !genderMale) { // Minimum for women
dailyCalories = 1200;
resultDiv.innerHTML = "Your estimated daily calorie target is " + Math.round(dailyCalories) + " calories. Note: For extreme weight loss, the calculated deficit was too large. We've capped it at 1200 calories, which is generally considered a minimum for women.";
} else if (dailyCalories < 1500 && genderMale) { // Minimum for men
dailyCalories = 1500;
resultDiv.innerHTML = "Your estimated daily calorie target is " + Math.round(dailyCalories) + " calories. Note: For extreme weight loss, the calculated deficit was too large. We've capped it at 1500 calories, which is generally considered a minimum for men.";
} else {
resultDiv.innerHTML = "Your estimated daily calorie target is " + Math.round(dailyCalories) + " calories.";
}
}
Understanding Your Daily Calorie Needs with MyFitnessPal
Whether your goal is to lose weight, gain muscle, or simply maintain your current physique, understanding your daily calorie needs is the cornerstone of effective nutrition planning. The MyFitnessPal Calorie Calculator provides a personalized estimate to help you achieve your health and fitness objectives.
What is a Calorie Calculator?
A calorie calculator is a tool that estimates the number of calories your body needs each day to perform its basic functions and support your activity level. It takes into account several factors, including your age, gender, weight, height, and physical activity, to provide a tailored recommendation.
Basal Metabolic Rate (BMR)
Your Basal Metabolic Rate (BMR) is the number of calories your body burns at rest to maintain vital functions like breathing, circulation, body temperature, and cell production. It's the minimum energy required to keep you alive. The calculator uses the Mifflin-St Jeor equation, which is widely recognized for its accuracy:
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
This formula provides a solid baseline for your energy expenditure before factoring in any physical activity.
Total Daily Energy Expenditure (TDEE)
While BMR accounts for your resting metabolism, your Total Daily Energy Expenditure (TDEE) includes the calories you burn through all daily activities, from walking to exercising. To calculate TDEE, your BMR is multiplied by an activity factor:
Very Active: BMR × 1.725 (hard exercise/sports 6-7 days a week)
Extra Active: BMR × 1.9 (very hard exercise/physical job/training twice a day)
Your TDEE is the number of calories you need to consume to maintain your current weight given your activity level.
Adjusting for Your Weight Goal
Once your TDEE is established, the calculator adjusts this number based on your specific weight goal:
Maintain Weight: Your TDEE is your target.
Mild Weight Loss (approx. 0.25 kg/week): TDEE – 250 calories
Weight Loss (approx. 0.5 kg/week): TDEE – 500 calories
Extreme Weight Loss (approx. 1 kg/week): TDEE – 1000 calories (Note: This is a significant deficit and should be approached with caution and professional guidance.)
Mild Weight Gain (approx. 0.25 kg/week): TDEE + 250 calories
Weight Gain (approx. 0.5 kg/week): TDEE + 500 calories
Extreme Weight Gain (approx. 1 kg/week): TDEE + 1000 calories
These adjustments create a calorie deficit or surplus, which is necessary for weight loss or gain, respectively. A deficit of 500 calories per day typically leads to a loss of about 0.5 kg (1 pound) per week, as 1 kg of fat is roughly equivalent to 7,700 calories.
Example Calculation:
Let's consider a 30-year-old female, weighing 65 kg, standing 165 cm tall, with a Moderately Active lifestyle, aiming for Weight Loss (0.5 kg/week):
Based on these inputs, her estimated daily calorie target for weight loss would be approximately 1624 calories.
Important Considerations:
Individual Variation: Metabolic rates can vary significantly between individuals due to genetics, body composition, and hormonal factors.
Nutrient Quality: While calorie count is important, the quality of your calories matters immensely. Focus on whole, unprocessed foods.
Listen to Your Body: These are estimates. Pay attention to your hunger cues, energy levels, and how your body responds.
Professional Advice: For specific dietary needs, medical conditions, or significant weight changes, always consult with a doctor or a registered dietitian.
Use this calculator as a starting point for your journey, and remember that consistency and a balanced approach are key to sustainable results.