Calorie Deficit Calculator
A calorie deficit occurs when you consume fewer calories than your body expends. This tool helps you select an evidence-backed deficit tier (15% conservative, 20% moderate, or 25% aggressive) to optimize adipose tissue loss while preserving metabolically active lean mass.
Your estimated daily maintenance energy (TDEE).
*Clinical estimate. Adjust gradually based on observed 14-day body weight trends.
Formula & Calculation Methodology
Calculates your maintenance energy (TDEE) and subtracts your selected deficit percentage. A 500 kcal daily deficit equates to ~3,500 kcal per week, historically linked to approximately 1 lb (0.45 kg) of adipose tissue mobilization.
Practical Example & Interpretation
If your maintenance expenditure is 2,400 kcal/day, a moderate 20% deficit creates a 480 kcal daily gap, setting your daily intake at 1,920 kcal. This projects to approximately 0.4 kg (0.9 lbs) of fat loss per week.
Assumptions & Clinical Disclaimers
Severe deficits exceeding 30% of maintenance intake risk muscle catabolism, micronutrient deficiencies, and hormonal downregulation. Never consume below 1,200 kcal/day for adult females or 1,500 kcal/day for adult males without medical supervision.