Calorie Calculator

BMR (Basal Metabolic Rate) is the number of calories your body burns at rest to maintain basic life functions like breathing and circulation. It represents the minimum calories needed if you stayed in bed all day.

TDEE (Total Daily Energy Expenditure) is your BMR plus the calories burned through daily activities and exercise. This is the number of calories you need to maintain your current weight.

To lose weight, create a calorie deficit by eating fewer calories than your TDEE. A deficit of 500 calories/day typically results in about 1 pound (0.45 kg) of weight loss per week.

This calculator uses the Mifflin-St Jeor equation, one of the most accurate BMR formulas. However, individual metabolism varies. Use the results as a starting point and adjust based on your actual progress.

Sedentary means little to no exercise (desk job, minimal movement). Lightly active includes light exercise 1-3 days/week. Moderately active means moderate exercise 3-5 days/week. Very active involves hard exercise 6-7 days/week. Extra active is for athletes training twice daily or those with physically demanding jobs.

To gain muscle, eat 250-500 calories above your TDEE, combined with strength training and adequate protein (1.6-2.2g per kg body weight). This creates a moderate surplus for muscle growth while minimizing fat gain. Gaining 0.25-0.5 kg per week is a healthy rate for muscle building.

Metabolism decreases about 2-3% per decade after age 30 due to loss of muscle mass, hormonal changes, and reduced physical activity. This is why the calculator accounts for age. Maintain metabolism through strength training to preserve muscle, staying active, and eating adequate protein.

Not necessarily. Calorie cycling (eating more on training days, less on rest days) can be effective. Weekly calorie totals matter more than daily precision. Some people prefer consistent daily intake for simplicity, while others adjust based on activity. Both approaches work if weekly averages align with goals.

Generally, women should not go below 1200 calories/day and men below 1500 calories/day without medical supervision. Very low calorie diets can cause nutrient deficiencies, muscle loss, hormonal imbalances, and metabolic slowdown. Aim for moderate deficits (15-25% below TDEE) for sustainable, healthy weight loss.

Track your weight for 2-3 weeks while eating at your calculated maintenance calories. If weight remains stable, your activity level is correct. If you're losing weight, increase to the next activity level. If gaining, decrease one level. Many people overestimate their activity level, so start conservatively.