Weight Loss Calculator
Calculate your calorie deficit and estimate your weight loss timeline.
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The Math of Weight Loss
Weight loss is fundamentally driven by a sustained negative energy balance. One pound of body fat contains approximately 3,500 calories.
Weekly Deficit = Total Daily Energy Expenditure (TDEE) - Daily Intake
TDEECalories burned daily (BMR + Activity)
Daily IntakeCalories consumed from food and drink
Net DeficitAmount used to burn stored body fat
Weight Loss Progression Examples
Scenario 1: Moderate Deficit
Daily Deficit500 kcal
Weekly Deficit3,500 kcal
Weight Loss1 lb / week
DifficultySustainable
💡 Info:Best for long-term lifestyle changes and muscle preservation.
Scenario 2: Aggressive Deficit
Daily Deficit1,000 kcal
Weekly Deficit7,000 kcal
Weight Loss2 lbs / week
DifficultyChallenging
⚠️ Warning:Requires meticulous tracking and high protein intake to prevent muscle loss.
⚡ Tips for Success
- Prioritize Protein: Aim for 0.7-1g of protein per pound of body weight to maintain muscle mass while losing fat.
- Be Honest with Activity: Most people overestimate how much they burn during exercise. Start with "Sedentary" if you have a desk job.
- The 80/20 Rule: Eat nutrient-dense foods 80% of the time, and allow yourself treats 20% of the time to maintain sanity.
Frequently Asked Questions
How many calories to lose 1 pound?
About 3,500 calories equals 1 pound. A 500 cal/day deficit = ~1 lb/week weight loss.
What is a safe rate of weight loss?
1-2 pounds per week is considered safe and sustainable. Faster loss can cause muscle loss.
Why am I not losing weight in a deficit?
Possible reasons: water retention, underestimating calories, metabolic adaptation, or gaining muscle.