Medical Disclaimer
This calculator is for informational and educational purposes only.
- Not Medical Advice: The information provided does not constitute medical advice, diagnosis, or treatment.
- Consult a Healthcare Professional: Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.
- No Doctor-Patient Relationship: Use of this calculator does not create a doctor-patient relationship.
- Accuracy Not Guaranteed: While we strive for accuracy, we make no warranties regarding the completeness, reliability, or accuracy of this information.
- Emergency Situations: Never disregard professional medical advice or delay in seeking it because of something you have calculated or read on this website.
Calorie Deficit Calculator
Calculate your daily calorie needs for weight loss using the scientifically-backed Mifflin-St Jeor equation. Get personalized recommendations based on your body metrics and activity level.
Science-Based
Uses the Mifflin-St Jeor equation, proven to be the most accurate BMR formula.
Safety Warnings
Get alerts when your calorie target is too aggressive for healthy weight loss.
100% Private
All calculations happen in your browser. Your health data stays with you.
Frequently Asked Questions
What is a calorie deficit?
A calorie deficit occurs when you consume fewer calories than your body burns. This forces your body to use stored fat for energy, resulting in weight loss. A deficit of 3,500 calories equals approximately 1 pound of fat loss.
How does the Mifflin-St Jeor equation work?
The Mifflin-St Jeor equation calculates your Basal Metabolic Rate (BMR) based on your age, gender, height, and weight. For men: (10 x weight in kg) + (6.25 x height in cm) - (5 x age) + 5. For women: (10 x weight in kg) + (6.25 x height in cm) - (5 x age) - 161.
What is TDEE?
TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a day, including your BMR plus calories burned through physical activity. Your TDEE is calculated by multiplying your BMR by an activity multiplier.
How much weight can I safely lose per week?
Most health professionals recommend losing 1-2 pounds per week for sustainable weight loss. Losing weight faster than this can lead to muscle loss, nutritional deficiencies, and metabolic slowdown.
What is the minimum safe calorie intake?
Generally, men should not consume fewer than 1,500 calories per day and women should not go below 1,200 calories without medical supervision. Eating too few calories can slow your metabolism and cause nutritional deficiencies.
Is this calculator free to use?
Yes! This calorie deficit calculator is 100% free with no sign-up required. All calculations happen in your browser, ensuring your personal health data stays private.