How a calorie deficit leads to weight loss
Your body draws on stored energy when you eat fewer calories than you burn. Roughly 7,700 calories equal one kilogram of body fat (about 3,500 per pound), so a daily deficit adds up predictably over a week. Multiply the daily deficit by seven and divide by that figure, and you get an estimated weekly loss — which the chart projects forward from your current weight.
Keep the deficit moderate
A moderate deficit of roughly 15–25% below maintenance is generally more sustainable and easier on your energy, mood and muscle than an aggressive cut. Very large deficits can be hard to stick to and may not be healthy. This tool is a rough planning estimate — real results vary with water weight, muscle and metabolism.
Why the estimate is approximate
Weight change isn't perfectly linear. Early drops often include water, metabolism adapts over time, and the 7,700-per-kilo rule is an average rather than an exact law. Use the projection as a direction of travel, not a guarantee, and adjust as you see real results.
Note: this is general information, not medical or nutritional advice. Talk to a qualified professional before making significant changes to your diet, especially if you have any health condition.
Frequently asked questions
What are maintenance calories (TDEE)?
It's the number of calories that keeps your weight stable — your total daily energy expenditure. You can estimate it with a BMI/TDEE calculator, then enter it here.
Is faster weight loss better?
Not usually. A steady, moderate pace is easier to maintain and helps preserve muscle. Extreme deficits often backfire and can be unhealthy.