Calorie Deficit Calculator

How This Calculator Works

Our calorie deficit calculator uses the Mifflin-St Jeor equation to calculate your Total Daily Energy Expenditure (TDEE), then determines the optimal calorie deficit based on your desired weight loss rate:

• TDEE Calculation: We calculate your Basal Metabolic Rate (BMR) and multiply it by your activity level to get your maintenance calories
• Calorie Deficit: Based on the principle that 1 pound of fat = 3,500 calories, we calculate your daily deficit needed
• Timeline Estimation: We project when you'll reach your goal weight based on consistent adherence to your calorie target

For a deeper understanding of calorie deficits, check out our comprehensive Calorie Deficit Guide.

Understanding Your Results

• TDEE (Maintenance Calories): The number of calories you burn each day including all activities. Eating at this level maintains your current weight.
• Daily Target Calories: The recommended calorie intake to achieve your desired weight loss rate while maintaining energy and health.
• Daily Deficit: The number of calories below your TDEE you need to maintain each day to reach your goal.
• Weekly Deficit: Your total weekly calorie reduction, which translates directly to fat loss over time.
• Timeline: An estimate of when you'll reach your goal weight based on consistent adherence to your calorie target.

Safe Weight Loss Guidelines

• Recommended Rate: 0.5-1 kg (1-2 lbs) per week is considered safe and sustainable for most people
• Minimum Calories: Don't go below 1,200 calories/day for women or 1,500 calories/day for men without medical supervision
• Maximum Deficit: Avoid deficits larger than 1,000 calories/day as they can slow metabolism and cause muscle loss
• Adjust as Needed: As you lose weight, your TDEE decreases, so recalculate every 5-10 pounds lost
• Listen to Your Body: If you feel extremely fatigued or hungry, your deficit may be too aggressive

Tips for Success

• Use our TDEE Calculator to understand your maintenance calories in detail
• Track your food intake consistently using Cal AI's AI-powered food recognition
• Weigh yourself regularly (same time, same conditions) to monitor progress
• Include strength training to preserve muscle mass during weight loss
• Be patient - sustainable weight loss takes time but creates lasting results
• Stay hydrated and prioritize protein to maintain satiety
• Plan for occasional higher calorie days to maintain adherence long-term

When to Consult a Professional

• If you have any underlying health conditions or take medications
• If you're pregnant, breastfeeding, or planning to become pregnant
• If you have a history of eating disorders
• If you're under 18 or over 65 years old
• If you need to lose a significant amount of weight (more than 50 lbs)

A registered dietitian or physician can provide personalized guidance for your specific situation.