Science-Based Weight Loss Calculator
Male
Female
Sedentary (Little/no exercise)
Lightly Active (1-3 days/week)
Moderately Active (3-5 days/week)
Very Active (6-7 days/week)
Extra Active (Physical job/Pro athlete)
Maintenance (Stay same weight)
Mild Weight Loss (0.25 kg/week)
Weight Loss (0.5 kg/week)
Extreme Weight Loss (1 kg/week)
Your Daily Caloric Roadmap
Basal Metabolic Rate (BMR):
0 kcal
Maintenance Calories (TDEE):
0 kcal
Target Daily Intake:
0 kcal
Note: It is generally not recommended for women to eat fewer than 1,200 calories or men fewer than 1,500 calories per day without medical supervision.
How Weight Loss Calculation Works
Sustainable weight loss is driven by the principle of energy balance. To lose weight, you must consume fewer calories than your body burns—a state known as a caloric deficit. This calculator uses the Mifflin-St Jeor Equation, which is currently considered the most accurate method for estimating metabolic rates in healthy adults.
Understanding the Metrics
- BMR (Basal Metabolic Rate): The number of calories your body burns at complete rest just to keep vital organs functioning (heart, lungs, brain).
- TDEE (Total Daily Energy Expenditure): This is your BMR adjusted for your physical activity level. This represents the "break-even" point where your weight stays the same.
- The Deficit: To lose 0.5 kg (roughly 1 lb) of fat per week, you generally need a deficit of approximately 500 calories per day, totaling 3,500 calories over the week.
Realistic Example:
A 35-year-old male, weighing 90kg and standing 180cm tall with a sedentary lifestyle, has a TDEE of approximately 2,250 calories. To lose 0.5kg per week, he would target 1,750 calories daily.
A 35-year-old male, weighing 90kg and standing 180cm tall with a sedentary lifestyle, has a TDEE of approximately 2,250 calories. To lose 0.5kg per week, he would target 1,750 calories daily.
Tips for Successful Weight Loss
While the math is straightforward, the application requires consistency. Prioritizing protein can help preserve muscle mass during a deficit, while high-fiber foods (vegetables) help manage hunger. Always consult with a healthcare professional before starting a new diet or exercise program, especially if you plan to target an "extreme" deficit.