Calorie Deficit Calculator
Male
Female
Sedentary (Office job, little exercise)
Lightly Active (Exercise 1-3 days/week)
Moderately Active (Exercise 3-5 days/week)
Very Active (Exercise 6-7 days/week)
Extra Active (Physical job or 2x daily training)
Lose 0.5 lb per week (Mild)
Lose 1 lb per week (Recommended)
Lose 1.5 lbs per week (Aggressive)
Lose 2 lbs per week (Very Aggressive)
Please fill in all fields with valid numbers.
Daily Calorie Budget
2,000
kcal / day
Maintenance Calories (TDEE):
–
Daily Deficit:
–
Projected Monthly Loss:
–
Understanding Calorie Deficit for Weight Loss
A calorie deficit occurs when you consume fewer calories than your body burns. This calculator uses the Mifflin-St Jeor Equation, widely considered the most accurate standard for estimating calorie needs. It calculates your Basal Metabolic Rate (BMR) and adjusts for your daily activity level to determine your Total Daily Energy Expenditure (TDEE).
How the Calculation Works
To lose weight effectively, you must understand the math behind your body's energy usage:
- BMR (Basal Metabolic Rate): The calories your body burns at complete rest just to keep organs functioning.
- TDEE (Total Daily Energy Expenditure): Your BMR multiplied by an activity factor. This is your "maintenance" number.
- The Deficit: One pound of body fat is roughly equivalent to 3,500 calories. To lose 1 lb per week, you need a total weekly deficit of 3,500 calories, or 500 calories per day.
Example Calculation
Let's look at a realistic example of how this works:
- Profile: 35-year-old male, 5'10" (70 inches), 200 lbs, with a desk job (Sedentary).
- Step 1 (BMR): The formula calculates a BMR of approximately 1,850 calories.
- Step 2 (TDEE): Multiplied by 1.2 (Sedentary), his maintenance level is 2,220 calories/day.
- Step 3 (Goal): To lose 1 lb/week, he subtracts 500 calories.
- Result: His target is 1,720 calories per day.
Safe Weight Loss Guidelines
While it might be tempting to maximize your deficit for faster results, experts recommend not losing more than 1-2 pounds per week. Drastically lowering your calorie intake (e.g., below 1,200 for women or 1,500 for men) can slow down your metabolism, cause muscle loss, and lead to nutritional deficiencies.
Tips for Success
Achieving a calorie deficit isn't just about eating less; it's about eating smarter. Focus on high-volume, low-calorie foods like vegetables and lean proteins to keep you full. Additionally, increasing your activity level (moving from "Sedentary" to "Lightly Active") can increase your calorie allowance, making the diet easier to sustain.