Calorie Deficit Calculator

Calculate the daily calorie deficit needed to reach your weight loss goal. Enter your stats, activity level, and target weight to get your custom plan.

Weight loss occurs when you consistently consume fewer calories than you burn. A deficit of 500 calories/day creates approximately 1 pound of fat loss per week. This calculator finds your TDEE (Total Daily Energy Expenditure) and sets your deficit target.

How calorie deficit works

  • 1 pound of fat ≈ 3,500 calories
  • 500 cal/day deficit → ~1 lb/week loss
  • 750 cal/day deficit → ~1.5 lb/week loss
  • 1,000 cal/day deficit → ~2 lb/week loss (general max recommended)

TDEE components

  • BMR: calories burned at rest (largest component, ~60–75%)
  • NEAT: Non-Exercise Activity Thermogenesis — fidgeting, walking, daily movement (~15–30%)
  • TEF: Thermic Effect of Food — digestion burns ~10% of calories consumed
  • EAT: Exercise Activity Thermogenesis — deliberate workouts (~5–15%)

Avoiding metabolic adaptation

When you cut calories significantly, your metabolism adapts by reducing NEAT and BMR. To prevent this: don't cut more than 1,000 cal/day, take diet breaks at maintenance every 4–6 weeks, maintain protein at 0.7–1 g/lb body weight, and include resistance training to preserve lean mass.

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