Daily Calorie Needs Calculator

Understanding Daily Calorie Needs

Your Total Daily Energy Expenditure (TDEE) represents the total number of calories you burn each day. It consists of your Basal Metabolic Rate (BMR) - the calories your body needs at rest - multiplied by an activity factor that accounts for physical activity.

Formulas Used

Mifflin-St Jeor Equation (1990)

Considered the most accurate formula for calculating BMR:

• Men: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) + 5
• Women: BMR = (10 x weight in kg) + (6.25 x height in cm) - (5 x age) - 161

Harris-Benedict Equation (Revised 1984)

A classic formula still widely used:

• Men: BMR = (13.397 x weight in kg) + (4.799 x height in cm) - (5.677 x age) + 88.362
• Women: BMR = (9.247 x weight in kg) + (3.098 x height in cm) - (4.330 x age) + 447.593

Activity Multipliers

Level	Factor	Description
Sedentary	1.2	Desk job, no exercise
Light	1.375	Light exercise 1-3 days/week
Moderate	1.55	Moderate exercise 3-5 days/week
Active	1.725	Hard exercise 6-7 days/week
Very Active	1.9	Physical job + hard exercise

Calorie Goals by Objective

Weight Loss

To lose weight safely, create a caloric deficit of 500-1000 calories per day, which typically results in 1-2 pounds of weight loss per week. Never go below 1200 calories (women) or 1500 calories (men) without medical supervision.

Weight Maintenance

Consume calories equal to your TDEE to maintain your current weight.

Weight Gain

To gain weight (particularly muscle mass), consume 300-500 calories above your TDEE combined with resistance training.

Factors Affecting Calorie Needs

• Age: Metabolism slows approximately 2% per decade after age 20
• Muscle Mass: More muscle increases metabolic rate
• Hormones: Thyroid function and other hormones affect metabolism
• Temperature: Cold environments increase calorie burn
• Health Conditions: Illness and recovery increase calorie needs