Calorie Calculator
Calculate your daily calorie needs based on age, weight, height, and activity level.
Daily Calorie Needs
2,633
kcal/day
Basal Metabolic Rate (BMR): 1,699 kcal
Lose weight fast (-500 kcal)
2,133 kcal
Lose weight slowly (-250 kcal)
2,383 kcal
Gain weight slowly (+250 kcal)
2,883 kcal
Gain weight fast (+500 kcal)
3,133 kcal
This calculator uses the Mifflin-St Jeor equation for estimating calorie needs. Results are approximate and should not replace professional medical or nutritional advice.
Understanding Calorie Needs and the Mifflin-St Jeor Equation
Calories are the unit of energy that our bodies use to function, from basic biological processes like breathing and circulating blood to physical activities like walking and exercising. Understanding your daily calorie needs is fundamental to managing your weight, whether your goal is to lose, maintain, or gain weight.
This calculator uses the Mifflin-St Jeor equation, which is considered the most accurate formula for estimating Basal Metabolic Rate (BMR) by the American Dietetic Association. The formula accounts for gender, age, weight, and height. For men: BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age - 5. For women: BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age - 161.
Your Total Daily Energy Expenditure (TDEE) is your BMR multiplied by an activity factor that accounts for your typical daily physical activity. The activity multipliers range from 1.2 for sedentary individuals to 1.9 for extremely active people. Your TDEE represents the total calories you need to maintain your current weight.
To lose weight, you need to create a calorie deficit by consuming fewer calories than your TDEE. A deficit of 500 calories per day results in approximately 1 pound (0.45 kg) of weight loss per week. To gain weight, you need a calorie surplus. Extreme deficits or surpluses are not recommended and should only be undertaken under medical supervision.
Common Use Cases
- Weight loss: determine your calorie target for a sustainable deficit
- Muscle building: calculate your calorie surplus for lean muscle gain
- Maintenance: find out how many calories you need to maintain your current weight
- Meal planning: use your daily target to plan balanced meals and snacks
- Fitness tracking: combine calorie awareness with exercise tracking for better results
Nutrition Tips
- ✓A moderate calorie deficit of 250-500 kcal per day is more sustainable than extreme restriction
- ✓Protein intake of 1.6-2.2g per kg of body weight supports muscle maintenance during weight loss
- ✓Do not go below 1,200 kcal/day (women) or 1,500 kcal/day (men) without medical supervision
- ✓Track your food intake for at least 2 weeks to get an accurate picture of your eating habits
- ✓Focus on nutrient-dense foods rather than just calorie counting for overall health
Frequently Asked Questions
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic life-sustaining functions like breathing, circulation, and cell production while at complete rest. TDEE (Total Daily Energy Expenditure) includes your BMR plus the calories burned through daily activities and exercise. TDEE is always higher than BMR.
How accurate is this calculator?
The Mifflin-St Jeor equation is considered the most accurate formula for estimating BMR, typically within 10% of actual values. However, individual metabolism varies based on genetics, body composition, hormonal factors, and other variables. Use this as a starting point and adjust based on your actual results.
Should I eat back the calories I burn from exercise?
If you have already accounted for your activity level in the calculator, your TDEE includes exercise. If you use the sedentary setting and exercise separately, you may eat back some (but typically not all) exercise calories, as calorie burn from exercise is often overestimated by fitness trackers.
Why do calorie needs decrease with age?
Calorie needs decrease with age primarily because of the natural loss of muscle mass (sarcopenia), which reduces BMR. Starting around age 30, adults lose approximately 3-8% of muscle mass per decade. Regular strength training can slow this decline and help maintain a higher metabolic rate.