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Enter Your Information
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Your Weight-Loss Plan
Fill in your body details and goal weight, then press Calculate Deficit to see your timeline and calorie options.
Understanding Your Results
What is a calorie deficit?
A calorie deficit happens when you eat fewer calories than your body burns. Over time, your body uses stored energy (mostly fat) to make up the difference, which leads to weight loss.
Why doesn't a 500-calorie deficit always equal 1 lb/week?
The old 3,500-calorie rule ignores metabolic adaptation. As you lose weight, your resting metabolism drops and the rate of loss slows. This calculator models that change week by week.
How low should my calories go?
As a general guideline, women should not go below 1,200 kcal/day and men not below 1,500 kcal/day without medical supervision.