Calorie Calculator
Calculate your daily calorie needs using the Mifflin-St Jeor equation. Get personalized results based on your age, gender, activity level, and weight goals.
How to Calculate Your Daily Calorie Needs
Calculating your daily calorie needs is the foundation of any successful nutrition plan. Whether you want to lose weight, build muscle, or simply maintain your current physique, knowing your calorie requirements gives you a clear target to work toward. Our calculator uses the Mifflin-St Jeor equation, which research has shown to be the most accurate formula for estimating Basal Metabolic Rate (BMR) in the general population.
Step 1: Determine Your BMR. Your Basal Metabolic Rate is the number of calories your body needs at complete rest to maintain vital functions like breathing, circulation, and cell production. The Mifflin-St Jeor equation calculates this based on your weight, height, age, and gender. For men, the formula is: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) + 5. For women, it is the same but subtracts 161 instead of adding 5.
Step 2: Factor in Activity Level. Your BMR only accounts for calories burned at rest. To find your Total Daily Energy Expenditure (TDEE), multiply your BMR by an activity factor. Sedentary individuals (desk jobs, no exercise) multiply by 1.2, while very active people (intense daily exercise) multiply by 1.725. Be honest about your activity level — overestimating is one of the most common mistakes people make.
Step 3: Adjust for Your Goal. Once you know your TDEE, adjust based on your goal. To lose weight, subtract 250-1000 calories per day (a 500-calorie deficit produces roughly 0.5 kg or 1 lb of fat loss per week). To gain weight, add 250-500 calories. For maintenance, eat at your TDEE level. Gradual changes are more sustainable and healthier than extreme deficits or surpluses.
Step 4: Consider Your Macros. Calories tell you how much to eat, but macronutrients tell you what to eat. A balanced approach of 30% protein, 40% carbohydrates, and 30% fat works well for most people. Protein is especially important during weight loss to preserve muscle mass — aim for at least 1.6g per kg of body weight if you are active.
Important Notes: These calculations provide estimates based on population averages. Individual metabolism can vary by 10-15% due to genetics, muscle mass, hormonal factors, and other variables. Track your progress over 2-3 weeks and adjust your intake by 100-200 calories if you are not seeing expected results. Always consult a healthcare professional before making significant dietary changes, especially if you have medical conditions.